1
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Li R, Sparveris N, Atac H, Jones MK, Paolone M, Akbar Z, Gayoso CA, Berdnikov V, Biswas D, Boer M, Camsonne A, Chen JP, Diefenthaler M, Duran B, Dutta D, Gaskell D, Hansen O, Hauenstein F, Heinrich N, Henry W, Horn T, Huber GM, Jia S, Joosten S, Karki A, Kay SJD, Kumar V, Li X, Li WB, Liyanage AH, Malace S, Markowitz P, McCaughan M, Meziani ZE, Mkrtchyan H, Morean C, Muhoza M, Narayan A, Pasquini B, Rehfuss M, Sawatzky B, Smith GR, Smith A, Trotta R, Yero C, Zheng X, Zhou J. Measured proton electromagnetic structure deviates from theoretical predictions. Nature 2022; 611:265-270. [PMID: 36261531 DOI: 10.1038/s41586-022-05248-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/17/2022] [Indexed: 11/09/2022]
Abstract
The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities1 that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities2 map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades2. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.
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Affiliation(s)
- R Li
- Temple University, Philadelphia, PA, USA
| | | | - H Atac
- Temple University, Philadelphia, PA, USA
| | - M K Jones
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - M Paolone
- New Mexico State University, Las Cruces, NM, USA
| | - Z Akbar
- University of Virginia, Charlottesville, VA, USA
| | | | - V Berdnikov
- Catholic University of America, Washington, DC, USA
| | - D Biswas
- Hampton University, Hampton, VA, USA.,Virginia Polytechnic Institute & State University, Blacksburg, VA, USA
| | - M Boer
- Temple University, Philadelphia, PA, USA.,Virginia Polytechnic Institute & State University, Blacksburg, VA, USA
| | - A Camsonne
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - J-P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - M Diefenthaler
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - B Duran
- Temple University, Philadelphia, PA, USA
| | - D Dutta
- Mississippi State University, Mississippi State, MS, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | | | - N Heinrich
- University of Regina, Regina, Saskatchewan, Canada
| | - W Henry
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - T Horn
- Catholic University of America, Washington, DC, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan, Canada
| | - S Jia
- Temple University, Philadelphia, PA, USA
| | - S Joosten
- Argonne National Laboratory, Lemont, IL, USA
| | - A Karki
- Mississippi State University, Mississippi State, MS, USA
| | - S J D Kay
- University of Regina, Regina, Saskatchewan, Canada
| | - V Kumar
- University of Regina, Regina, Saskatchewan, Canada
| | - X Li
- Duke University, Durham, NC, USA
| | - W B Li
- The College of William and Mary, Williamsburg, VA, USA
| | | | - S Malace
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - P Markowitz
- Florida International University, University Park, FL, USA
| | - M McCaughan
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - Z-E Meziani
- Argonne National Laboratory, Lemont, IL, USA
| | - H Mkrtchyan
- Artem Alikhanian National Laboratory, Yerevan, Armenia
| | - C Morean
- University of Tennessee, Knoxville, TN, USA
| | - M Muhoza
- Catholic University of America, Washington, DC, USA
| | - A Narayan
- Veer Kunwar Singh University, Arrah, India
| | - B Pasquini
- University of Pavia, Pavia, Italy.,Istituto Nazionale di Fisica Nucleare (INFN), Pavia, Italy
| | - M Rehfuss
- Temple University, Philadelphia, PA, USA
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, VA, USA
| | - A Smith
- Duke University, Durham, NC, USA
| | - R Trotta
- Catholic University of America, Washington, DC, USA
| | - C Yero
- Florida International University, University Park, FL, USA
| | - X Zheng
- University of Virginia, Charlottesville, VA, USA
| | - J Zhou
- Duke University, Durham, NC, USA
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2
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Georges F, Rashad MNH, Stefanko A, Dlamini M, Karki B, Ali SF, Lin PJ, Ko HS, Israel N, Adikaram D, Ahmed Z, Albataineh H, Aljawrneh B, Allada K, Allison S, Alsalmi S, Androic D, Aniol K, Annand J, Atac H, Averett T, Ayerbe Gayoso C, Bai X, Bane J, Barcus S, Bartlett K, Bellini V, Beminiwattha R, Bericic J, Biswas D, Brash E, Bulumulla D, Campbell J, Camsonne A, Carmignotto M, Castellano J, Chen C, Chen JP, Chetry T, Christy ME, Cisbani E, Clary B, Cohen E, Compton N, Cornejo JC, Covrig Dusa S, Crowe B, Danagoulian S, Danley T, De Persio F, Deconinck W, Defurne M, Desnault C, Di D, Duer M, Duran B, Ent R, Fanelli C, Franklin G, Fuchey E, Gal C, Gaskell D, Gautam T, Glamazdin O, Gnanvo K, Gray VM, Gu C, Hague T, Hamad G, Hamilton D, Hamilton K, Hansen O, Hauenstein F, Henry W, Higinbotham DW, Holmstrom T, Horn T, Huang Y, Huber GM, Hyde CE, Ibrahim H, Jen CM, Jin K, Jones M, Kabir A, Keppel C, Khachatryan V, King PM, Li S, Li WB, Liu J, Liu H, Liyanage A, Magee J, Malace S, Mammei J, Markowitz P, McClellan E, Mazouz M, Meddi F, Meekins D, Mesik K, Michaels R, Mkrtchyan A, Montgomery R, Muñoz Camacho C, Myers LS, Nadel-Turonski P, Nazeer SJ, Nelyubin V, Nguyen D, Nuruzzaman N, Nycz M, Obretch OF, Ou L, Palatchi C, Pandey B, Park S, Park K, Peng C, Pomatsalyuk R, Pooser E, Puckett AJR, Punjabi V, Quinn B, Rahman S, Reimer PE, Roche J, Sapkota I, Sarty A, Sawatzky B, Saylor NH, Schmookler B, Shabestari MH, Shahinyan A, Sirca S, Smith GR, Sooriyaarachchilage S, Sparveris N, Spies R, Su T, Subedi A, Sulkosky V, Sun A, Thorne L, Tian Y, Ton N, Tortorici F, Trotta R, Urciuoli GM, Voutier E, Waidyawansa B, Wang Y, Wojtsekhowski B, Wood S, Yan X, Ye L, Ye Z, Yero C, Zhang J, Zhao Y, Zhu P. Deeply Virtual Compton Scattering Cross Section at High Bjorken x_{B}. Phys Rev Lett 2022; 128:252002. [PMID: 35802440 DOI: 10.1103/physrevlett.128.252002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 03/28/2022] [Accepted: 04/18/2022] [Indexed: 06/15/2023]
Abstract
We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.
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Affiliation(s)
- F Georges
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - M N H Rashad
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - A Stefanko
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - M Dlamini
- Ohio University, Athens, Ohio 45701, USA
| | - B Karki
- Ohio University, Athens, Ohio 45701, USA
| | - S F Ali
- Catholic University of America, Washington, DC 20064, USA
| | - P-J Lin
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - H-S Ko
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
- Seoul National University, 1 Gwanak-ro, Gwanak-gu, 08826 Seoul, Korea
| | - N Israel
- Ohio University, Athens, Ohio 45701, USA
| | - D Adikaram
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan, S4S 0A2 Canada
| | - H Albataineh
- Texas A&M University-Kingsville, Kingsville, Texas 78363, USA
| | - B Aljawrneh
- North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, USA
| | - K Allada
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S Allison
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - S Alsalmi
- Kent State University, Kent, Ohio 44240, USA
| | - D Androic
- University of Zagreb, Trg Republike Hrvatske 14, 10000 Zagreb, Croatia
| | - K Aniol
- California State University, Los Angeles, Los Angeles, California 90032, USA
| | - J Annand
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H Atac
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - T Averett
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - C Ayerbe Gayoso
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - X Bai
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - J Bane
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Barcus
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - K Bartlett
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - V Bellini
- Istituto Nazionale di Fisica Nucleare, Dipartimento di Fisica delle Università degli di Catania, I-95123 Catania, Italy
| | | | - J Bericic
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D Biswas
- Hampton University, Hampton, Virginia 23669, USA
| | - E Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | - D Bulumulla
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - J Campbell
- Dalhousie University, Nova Scotia, NS B3H 4R2, Canada
| | - A Camsonne
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Carmignotto
- Catholic University of America, Washington, DC 20064, USA
| | - J Castellano
- Florida International University, Miami, Florida 33199, USA
| | - C Chen
- Hampton University, Hampton, Virginia 23669, USA
| | - J-P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Chetry
- Ohio University, Athens, Ohio 45701, USA
| | - M E Christy
- Hampton University, Hampton, Virginia 23669, USA
| | - E Cisbani
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, Piazzale Aldo Moro, 2-00185 Roma, Italy
| | - B Clary
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - E Cohen
- Tel Aviv University, Tel Aviv-Yafo 6997801, Israel
| | - N Compton
- Ohio University, Athens, Ohio 45701, USA
| | - J C Cornejo
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - S Covrig Dusa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Crowe
- North Carolina Central University, Durham, North Carolina 27707, USA
| | - S Danagoulian
- North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, USA
| | - T Danley
- Ohio University, Athens, Ohio 45701, USA
| | - F De Persio
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, Piazzale Aldo Moro, 2-00185 Roma, Italy
| | - W Deconinck
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - M Defurne
- CEA Saclay, 91191 Gif-sur-Yvette, France
| | - C Desnault
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - D Di
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - M Duer
- Tel Aviv University, Tel Aviv-Yafo 6997801, Israel
| | - B Duran
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Fanelli
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - G Franklin
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - E Fuchey
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - C Gal
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Gautam
- Hampton University, Hampton, Virginia 23669, USA
| | - O Glamazdin
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - K Gnanvo
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - V M Gray
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - C Gu
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - T Hague
- Kent State University, Kent, Ohio 44240, USA
| | - G Hamad
- Ohio University, Athens, Ohio 45701, USA
| | - D Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - K Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Hauenstein
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - W Henry
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - D W Higinbotham
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Holmstrom
- Longwood University, Farmville, Virginia 23901, USA
| | - T Horn
- Catholic University of America, Washington, DC 20064, USA
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Y Huang
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan, S4S 0A2 Canada
| | - C E Hyde
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - H Ibrahim
- Cairo University, Cairo 121613, Egypt
| | - C-M Jen
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 234061, USA
| | - K Jin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - M Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Kabir
- Kent State University, Kent, Ohio 44240, USA
| | - C Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Khachatryan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- Stony Brook, State University of New York, New York 11794, USA
- Cornell University, Ithaca, New York 14853, USA
| | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - S Li
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W B Li
- University of Regina, Regina, Saskatchewan, S4S 0A2 Canada
| | - J Liu
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - H Liu
- Columbia University, New York, New York 10027, USA
| | - A Liyanage
- Hampton University, Hampton, Virginia 23669, USA
| | - J Magee
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - S Malace
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Mammei
- University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - P Markowitz
- Florida International University, Miami, Florida 33199, USA
| | - E McClellan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Mazouz
- Faculté des Sciences de Monastir, Monastir 5019, Tunisia
| | - F Meddi
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, Piazzale Aldo Moro, 2-00185 Roma, Italy
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Mesik
- Rutgers University, New Brunswick, New Jersey 08854, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Mkrtchyan
- Catholic University of America, Washington, DC 20064, USA
| | - R Montgomery
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - C Muñoz Camacho
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - L S Myers
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P Nadel-Turonski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S J Nazeer
- Hampton University, Hampton, Virginia 23669, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - D Nguyen
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - N Nuruzzaman
- Hampton University, Hampton, Virginia 23669, USA
| | - M Nycz
- Kent State University, Kent, Ohio 44240, USA
| | - O F Obretch
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - L Ou
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C Palatchi
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - B Pandey
- Hampton University, Hampton, Virginia 23669, USA
| | - S Park
- Stony Brook, State University of New York, New York 11794, USA
| | - K Park
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - C Peng
- Duke University, Durham, North Carolina 27708, USA
| | - R Pomatsalyuk
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - E Pooser
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A J R Puckett
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - B Quinn
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S Rahman
- University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - P E Reimer
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - J Roche
- Ohio University, Athens, Ohio 45701, USA
| | - I Sapkota
- Catholic University of America, Washington, DC 20064, USA
| | - A Sarty
- Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N H Saylor
- Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - B Schmookler
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M H Shabestari
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - A Shahinyan
- AANL, 2 Alikhanian Brothers Street, 0036 Yerevan, Armenia
| | - S Sirca
- Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - N Sparveris
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Spies
- University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - T Su
- Kent State University, Kent, Ohio 44240, USA
| | - A Subedi
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - V Sulkosky
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - A Sun
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - L Thorne
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Y Tian
- Shandong University, Jinan 250100, China
| | - N Ton
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - F Tortorici
- Istituto Nazionale di Fisica Nucleare, Dipartimento di Fisica delle Università degli di Catania, I-95123 Catania, Italy
| | - R Trotta
- Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA
| | - G M Urciuoli
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, Piazzale Aldo Moro, 2-00185 Roma, Italy
| | - E Voutier
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - B Waidyawansa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Y Wang
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - B Wojtsekhowski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - X Yan
- Huangshan University, Tunxi, Daizhen Road 245041, China
| | - L Ye
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - Z Ye
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - C Yero
- Florida International University, Miami, Florida 33199, USA
| | - J Zhang
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - Y Zhao
- Stony Brook, State University of New York, New York 11794, USA
| | - P Zhu
- University of Science and Technology of China, Hefei, Anhui 230026, China
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3
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Androić D, Armstrong DS, Bartlett K, Beminiwattha RS, Benesch J, Benmokhtar F, Birchall J, Carlini RD, Cornejo JC, Covrig Dusa S, Dalton MM, Davis CA, Deconinck W, Dowd JF, Dunne JA, Dutta D, Duvall WS, Elaasar M, Falk WR, Finn JM, Forest T, Gal C, Gaskell D, Gericke MTW, Gray VM, Grimm K, Guo F, Hoskins JR, Jones DC, Jones MK, Kargiantoulakis M, King PM, Korkmaz E, Kowalski S, Leacock J, Leckey J, Lee AR, Lee JH, Lee L, MacEwan S, Mack D, Magee JA, Mahurin R, Mammei J, Martin JW, McHugh MJ, Meekins D, Mesick KE, Michaels R, Micherdzinska A, Mkrtchyan A, Mkrtchyan H, Narayan A, Ndukum LZ, Nelyubin V, van Oers WTH, Owen VF, Page SA, Pan J, Paschke KD, Phillips SK, Pitt ML, Radloff RW, Rajotte JF, Ramsay WD, Roche J, Sawatzky B, Seva T, Shabestari MH, Silwal R, Simicevic N, Smith GR, Solvignon P, Spayde DT, Subedi A, Suleiman R, Tadevosyan V, Tobias WA, Tvaskis V, Waidyawansa B, Wang P, Wells SP, Wood SA, Yang S, Zang P, Zhamkochyan S, Christy ME, Horowitz CJ, Fattoyev FJ, Lin Z. Determination of the ^{27}Al Neutron Distribution Radius from a Parity-Violating Electron Scattering Measurement. Phys Rev Lett 2022; 128:132501. [PMID: 35426696 DOI: 10.1103/physrevlett.128.132501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst) ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010 GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157 GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15 fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15 fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.
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Affiliation(s)
- D Androić
- University of Zagreb, Zagreb, HR 10002, Croatia
| | | | - K Bartlett
- William & Mary, Williamsburg, Virginia 23185, USA
| | | | - J Benesch
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Benmokhtar
- Christopher Newport University, Newport News, Virginia 23606, USA
| | - J Birchall
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - R D Carlini
- William & Mary, Williamsburg, Virginia 23185, USA
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J C Cornejo
- William & Mary, Williamsburg, Virginia 23185, USA
| | - S Covrig Dusa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M M Dalton
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - C A Davis
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - W Deconinck
- William & Mary, Williamsburg, Virginia 23185, USA
| | - J F Dowd
- William & Mary, Williamsburg, Virginia 23185, USA
| | - J A Dunne
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Dutta
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - W S Duvall
- Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | - M Elaasar
- Southern University at New Orleans, New Orleans, Louisiana 70126, USA
| | - W R Falk
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J M Finn
- William & Mary, Williamsburg, Virginia 23185, USA
| | - T Forest
- Idaho State University, Pocatello, Idaho 83209, USA
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - C Gal
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M T W Gericke
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - V M Gray
- William & Mary, Williamsburg, Virginia 23185, USA
| | - K Grimm
- William & Mary, Williamsburg, Virginia 23185, USA
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - F Guo
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J R Hoskins
- William & Mary, Williamsburg, Virginia 23185, USA
| | - D C Jones
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - M K Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - E Korkmaz
- University of Northern British Columbia, Prince George, British Columbia V2N4Z9, Canada
| | - S Kowalski
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J Leacock
- Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | - J Leckey
- William & Mary, Williamsburg, Virginia 23185, USA
| | - A R Lee
- Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | - J H Lee
- William & Mary, Williamsburg, Virginia 23185, USA
- Ohio University, Athens, Ohio 45701, USA
| | - L Lee
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - S MacEwan
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - D Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J A Magee
- William & Mary, Williamsburg, Virginia 23185, USA
| | - R Mahurin
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J Mammei
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | - J W Martin
- University of Winnipeg, Winnipeg, Manitoba R3B2E9, Canada
| | - M J McHugh
- George Washington University, Washington, DC 20052, USA
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K E Mesick
- George Washington University, Washington, DC 20052, USA
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - A Mkrtchyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - H Mkrtchyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - A Narayan
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - L Z Ndukum
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - W T H van Oers
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - V F Owen
- William & Mary, Williamsburg, Virginia 23185, USA
| | - S A Page
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J Pan
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - K D Paschke
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - S K Phillips
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - M L Pitt
- Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
| | | | - J F Rajotte
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - W D Ramsay
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - J Roche
- Ohio University, Athens, Ohio 45701, USA
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Seva
- University of Zagreb, Zagreb, HR 10002, Croatia
| | - M H Shabestari
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Silwal
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - N Simicevic
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P Solvignon
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D T Spayde
- Hendrix College, Conway, Arkansas 72032, USA
| | - A Subedi
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Suleiman
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Tadevosyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - W A Tobias
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - V Tvaskis
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- University of Winnipeg, Winnipeg, Manitoba R3B2E9, Canada
| | | | - P Wang
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - S P Wells
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - S A Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Yang
- William & Mary, Williamsburg, Virginia 23185, USA
| | - P Zang
- Syracuse University, Syracuse, New York 13244, USA
| | - S Zhamkochyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - M E Christy
- Hampton University, Hampton, Virginia 23668, USA
| | - C J Horowitz
- Indiana University, Bloomington, Indiana 47405, USA
| | - F J Fattoyev
- Indiana University, Bloomington, Indiana 47405, USA
| | - Z Lin
- Indiana University, Bloomington, Indiana 47405, USA
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4
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Christy ME, Gautam T, Ou L, Schmookler B, Wang Y, Adikaram D, Ahmed Z, Albataineh H, Ali SF, Aljawrneh B, Allada K, Allison SL, Alsalmi S, Androic D, Aniol K, Annand J, Arrington J, Atac H, Averett T, Ayerbe Gayoso C, Bai X, Bane J, Barcus S, Bartlett K, Bellini V, Beminiwattha R, Bericic J, Bhatt H, Bhetuwal D, Biswas D, Brash E, Bulumulla D, Camacho CM, Campbell J, Camsonne A, Carmignotto M, Castellanos J, Chen C, Chen JP, Chetry T, Cisbani E, Clary B, Cohen E, Compton N, Cornejo JC, Covrig Dusa S, Crowe B, Danagoulian S, Danley T, Deconinck W, Defurne M, Desnault C, Di D, Dlamini M, Duer M, Duran B, Ent R, Fanelli C, Fuchey E, Gal C, Gaskell D, Georges F, Gilad S, Glamazdin O, Gnanvo K, Gramolin AV, Gray VM, Gu C, Habarakada A, Hague T, Hamad G, Hamilton D, Hamilton K, Hansen O, Hauenstein F, Hernandez AV, Henry W, Higinbotham DW, Holmstrom T, Horn T, Huang Y, Huber GM, Hyde C, Ibrahim H, Israel N, Jen CM, Jin K, Jones M, Kabir A, Karki B, Keppel C, Khachatryan V, King PM, Li S, Li W, Liu H, Liu J, Liyanage AH, Mack D, Magee J, Malace S, Mammei J, Markowitz P, Mayilyan S, McClellan E, Meddi F, Meekins D, Mesick K, Michaels R, Mkrtchyan A, Moffit B, Montgomery R, Myers LS, Nadel-Turonski P, Nazeer SJ, Nelyubin V, Nguyen D, Nuruzzaman N, Nycz M, Obrecht RF, Ohanyan K, Palatchi C, Pandey B, Park K, Park S, Peng C, Persio FD, Pomatsalyuk R, Pooser E, Puckett AJR, Punjabi V, Quinn B, Rahman S, Rashad MNH, Reimer PE, Riordan S, Roche J, Sapkota I, Sarty A, Sawatzky B, Saylor NH, Shabestari MH, Shahinyan A, Širca S, Smith GR, Sooriyaarachchilage S, Sparveris N, Spies R, Stefanko A, Su T, Subedi A, Sulkosky V, Sun A, Tan Y, Thorne L, Ton N, Tortorici F, Trotta R, Uniyal R, Urciuoli GM, Voutier E, Waidyawansa B, Wojtsekhowski B, Wood S, Yan X, Ye L, Ye ZH, Yero C, Zhang J, Zhao YX, Zhu P. Form Factors and Two-Photon Exchange in High-Energy Elastic Electron-Proton Scattering. Phys Rev Lett 2022; 128:102002. [PMID: 35333083 DOI: 10.1103/physrevlett.128.102002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 11/06/2021] [Accepted: 01/31/2022] [Indexed: 06/14/2023]
Abstract
We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75 (GeV/c)^{2}. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q^{2} and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q^{2} and attributed to hard two-photon exchange (TPE) effects, extending to 8 (GeV/c)^{2} the range of Q^{2} for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q^{2}.
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Affiliation(s)
- M E Christy
- Hampton University, Hampton, Virginia 23669, USA
| | - T Gautam
- Hampton University, Hampton, Virginia 23669, USA
| | - L Ou
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - B Schmookler
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Y Wang
- William and Mary, Williamsburg, Virginia 23185, USA
| | - D Adikaram
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - H Albataineh
- Texas A & M University, Kingsville, Texas 77843, USA
| | - S F Ali
- Catholic University of America, Washington, District of Columbia 20064, USA
| | - B Aljawrneh
- North Carolina A&T State University, Greensboro, North Carolina 27411, USA
- Al Zaytoonah University of Jordan, Amman 11733, Jordan
| | - K Allada
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S L Allison
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - S Alsalmi
- Kent State University, Kent, Ohio 44240, USA
| | - D Androic
- University of Zagreb, Trg Republike Hrvatske 14, 10000, Zagreb, Croatia
| | - K Aniol
- California State University, Los Angeles, Los Angeles, California 90032, USA
| | - J Annand
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - J Arrington
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - H Atac
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - T Averett
- William and Mary, Williamsburg, Virginia 23185, USA
| | | | - X Bai
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - J Bane
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Barcus
- William and Mary, Williamsburg, Virginia 23185, USA
| | - K Bartlett
- William and Mary, Williamsburg, Virginia 23185, USA
| | - V Bellini
- Istituto Nazionale di Fisica Nucleare, Department of Physics and Astronomy, I-95123 Catania, Italy
| | | | - J Bericic
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - H Bhatt
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Bhetuwal
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Biswas
- Hampton University, Hampton, Virginia 23669, USA
| | - E Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | - D Bulumulla
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - C M Camacho
- Institut de Physique Nucleaire, 15 Rue Georges Clemenceau, 91400 Orsay, France
| | - J Campbell
- Dalhousie University, Nova Scotia NS B3H 4R2, Canada
| | - A Camsonne
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Carmignotto
- Catholic University of America, Washington, DC 20064, USA
| | - J Castellanos
- Florida International University, Miami, Florida 33199, USA
| | - C Chen
- Hampton University, Hampton, Virginia 23669, USA
| | - J-P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Chetry
- Ohio University, Athens, Ohio 45701, USA
| | - E Cisbani
- Istituto Nazionale di Fisica Nucleare - Sezione di Roma, P.le Aldo Moro, 2 - 00185 Roma, Italy
| | - B Clary
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - E Cohen
- Tel Aviv University, Tel Aviv-Yafo 69978, Israel
| | - N Compton
- Ohio University, Athens, Ohio 45701, USA
| | - J C Cornejo
- William and Mary, Williamsburg, Virginia 23185, USA
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S Covrig Dusa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Crowe
- North Carolina Central University, Durham, North Carolina 27707, USA
| | - S Danagoulian
- North Carolina A&T State University, Greensboro, North Carolina 27411, USA
| | - T Danley
- Ohio University, Athens, Ohio 45701, USA
| | - W Deconinck
- William and Mary, Williamsburg, Virginia 23185, USA
| | - M Defurne
- CEA Saclay, 91191 Gif-sur-Yvette, France
| | - C Desnault
- Institut de Physique Nucleaire, 15 Rue Georges Clemenceau, 91400 Orsay, France
| | - D Di
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - M Dlamini
- Ohio University, Athens, Ohio 45701, USA
| | - M Duer
- Tel Aviv University, Tel Aviv-Yafo 69978, Israel
| | - B Duran
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Fanelli
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - E Fuchey
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - C Gal
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Georges
- Ecole Centrale Paris, 3 Rue Joliot Curie, 91190 Gif-sur-Yvette, France
| | - S Gilad
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - O Glamazdin
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - K Gnanvo
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - A V Gramolin
- Boston University, Boston, Massachusetts 02215, USA
| | - V M Gray
- William and Mary, Williamsburg, Virginia 23185, USA
| | - C Gu
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - A Habarakada
- Hampton University, Hampton, Virginia 23669, USA
| | - T Hague
- Kent State University, Kent, Ohio 44240, USA
| | - G Hamad
- Ohio University, Athens, Ohio 45701, USA
| | - D Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - K Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Hauenstein
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - A V Hernandez
- Catholic University of America, Washington, DC 20064, USA
| | - W Henry
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - D W Higinbotham
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Holmstrom
- Randolph Macon College, Ashland, Virginia 23005, USA
| | - T Horn
- Catholic University of America, Washington, DC 20064, USA
| | - Y Huang
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - C Hyde
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - H Ibrahim
- Cairo University, Cairo, 12613, Egypt
| | - N Israel
- Ohio University, Athens, Ohio 45701, USA
| | - C-M Jen
- Virginia Polytechnic Institute and State University, Blacksburg, Virginia 234061, USA
| | - K Jin
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - M Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Kabir
- Kent State University, Kent, Ohio 44240, USA
| | - B Karki
- Ohio University, Athens, Ohio 45701, USA
| | - C Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Khachatryan
- Stony Brook, State University of New York, New York 11794, USA
- Cornell University, Ithaca, New York 14853, USA
| | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - S Li
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W Li
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - H Liu
- Columbia University, New York, New York 10027, USA
| | - J Liu
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - A H Liyanage
- Hampton University, Hampton, Virginia 23669, USA
| | - D Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Magee
- William and Mary, Williamsburg, Virginia 23185, USA
| | - S Malace
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Mammei
- University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - P Markowitz
- Florida International University, Miami, Florida 33199, USA
| | - S Mayilyan
- AANL, 2 Alikhanian Brothers Street, 0036 Yerevan, Armenia
| | - E McClellan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Meddi
- Istituto Nazionale di Fisica Nucleare - Sezione di Roma, P.le Aldo Moro, 2 - 00185 Roma, Italy
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Mesick
- Rutgers University, New Brunswick, New Jersey 08854, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Mkrtchyan
- Catholic University of America, Washington, DC 20064, USA
| | - B Moffit
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R Montgomery
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - L S Myers
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P Nadel-Turonski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S J Nazeer
- Hampton University, Hampton, Virginia 23669, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - D Nguyen
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - N Nuruzzaman
- Hampton University, Hampton, Virginia 23669, USA
| | - M Nycz
- Kent State University, Kent, Ohio 44240, USA
| | - R F Obrecht
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - K Ohanyan
- AANL, 2 Alikhanian Brothers Street, 0036 Yerevan, Armenia
| | - C Palatchi
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - B Pandey
- Hampton University, Hampton, Virginia 23669, USA
| | - K Park
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - S Park
- Stony Brook, State University of New York, New York 11794, USA
| | - C Peng
- Duke University, Durham, North Carolina 27708, USA
| | - F D Persio
- Istituto Nazionale di Fisica Nucleare - Sezione di Roma, P.le Aldo Moro, 2 - 00185 Roma, Italy
| | - R Pomatsalyuk
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - E Pooser
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A J R Puckett
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - B Quinn
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S Rahman
- University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - M N H Rashad
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - P E Reimer
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - S Riordan
- Stony Brook, State University of New York, New York 11794, USA
| | - J Roche
- Ohio University, Athens, Ohio 45701, USA
| | - I Sapkota
- Catholic University of America, Washington, DC 20064, USA
| | - A Sarty
- Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N H Saylor
- Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - M H Shabestari
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - A Shahinyan
- AANL, 2 Alikhanian Brothers Street, 0036 Yerevan, Armenia
| | - S Širca
- Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - N Sparveris
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Spies
- University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - A Stefanko
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - T Su
- Kent State University, Kent, Ohio 44240, USA
| | - A Subedi
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - V Sulkosky
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A Sun
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Y Tan
- Shandong University, Shandong, Jinan 250100, China
| | - L Thorne
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - N Ton
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - F Tortorici
- Istituto Nazionale di Fisica Nucleare, Department of Physics and Astronomy, I-95123 Catania, Italy
| | - R Trotta
- Duquesne University, Pittsburgh, Pennsylvania 15282, USA
| | - R Uniyal
- Catholic University of America, Washington, DC 20064, USA
| | - G M Urciuoli
- Istituto Nazionale di Fisica Nucleare - Sezione di Roma, P.le Aldo Moro, 2 - 00185 Roma, Italy
| | - E Voutier
- Institut de Physique Nucleaire, 15 Rue Georges Clemenceau, 91400 Orsay, France
| | - B Waidyawansa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Wojtsekhowski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - X Yan
- Huangshan University, 44 Daizhen Road, Tunxi District, Huangshan, Anhui Province, China
| | - L Ye
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - Z H Ye
- University of Virginia, Charlottesville, Virginia 232904, USA
- Tsinghua University, 30 Shuangqing Rd, Haidian District, Beijing 100190, China
| | - C Yero
- Florida International University, Miami, Florida 33199, USA
| | - J Zhang
- University of Virginia, Charlottesville, Virginia 232904, USA
| | - Y X Zhao
- Stony Brook, State University of New York, New York 11794, USA
| | - P Zhu
- University of Science and Technology of China, Hefei, Anhui 230026, China
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Dlamini M, Karki B, Ali SF, Lin PJ, Georges F, Ko HS, Israel N, Rashad MNH, Stefanko A, Adikaram D, Ahmed Z, Albataineh H, Aljawrneh B, Allada K, Allison S, Alsalmi S, Androic D, Aniol K, Annand J, Atac H, Averett T, Ayerbe Gayoso C, Bai X, Bane J, Barcus S, Bartlett K, Bellini V, Beminiwattha R, Bericic J, Biswas D, Brash E, Bulumulla D, Campbell J, Camsonne A, Carmignotto M, Castellano J, Chen C, Chen JP, Chetry T, Christy ME, Cisbani E, Clary B, Cohen E, Compton N, Cornejo JC, Covrig Dusa S, Crowe B, Danagoulian S, Danley T, De Persio F, Deconinck W, Defurne M, Desnault C, Di D, Duer M, Duran B, Ent R, Fanelli C, Franklin G, Fuchey E, Gal C, Gaskell D, Gautam T, Glamazdin O, Gnanvo K, Gray VM, Gu C, Hague T, Hamad G, Hamilton D, Hamilton K, Hansen O, Hauenstein F, Henry W, Higinbotham DW, Holmstrom T, Horn T, Huang Y, Huber GM, Hyde C, Ibrahim H, Jen CM, Jin K, Jones M, Kabir A, Keppel C, Khachatryan V, King PM, Li S, Li W, Liu J, Liu H, Liyanage A, Magee J, Malace S, Mammei J, Markowitz P, McClellan E, Meddi F, Meekins D, Mesik K, Michaels R, Mkrtchyan A, Montgomery R, Muñoz Camacho C, Myers LS, Nadel-Turonski P, Nazeer SJ, Nelyubin V, Nguyen D, Nuruzzaman N, Nycz M, Obretch OF, Ou L, Palatchi C, Pandey B, Park S, Park K, Peng C, Pomatsalyuk R, Pooser E, Puckett AJR, Punjabi V, Quinn B, Rahman S, Reimer PE, Roche J, Sapkota I, Sarty A, Sawatzky B, Saylor NH, Schmookler B, Shabestari MH, Shahinyan A, Sirca S, Smith GR, Sooriyaarachchilage S, Sparveris N, Spies R, Su T, Subedi A, Sulkosky V, Sun A, Thorne L, Tian Y, Ton N, Tortorici F, Trotta R, Urciuoli GM, Voutier E, Waidyawansa B, Wang Y, Wojtsekhowski B, Wood S, Yan X, Ye L, Ye Z, Yero C, Zhang J, Zhao Y, Zhu P. Deep Exclusive Electroproduction of π^{0} at High Q^{2} in the Quark Valence Regime. Phys Rev Lett 2021; 127:152301. [PMID: 34678020 DOI: 10.1103/physrevlett.127.152301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 06/07/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4 GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.
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Affiliation(s)
- M Dlamini
- Ohio University, Athens, Ohio 45701, USA
| | - B Karki
- Ohio University, Athens, Ohio 45701, USA
| | - S F Ali
- Catholic University of America, Washington, DC 20064, USA
| | - P-J Lin
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - F Georges
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - H-S Ko
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
- Seoul National University, 1 Gwanak-ro, Gwanak-gu, 08826 Seoul, Korea
| | - N Israel
- Ohio University, Athens, Ohio 45701, USA
| | - M N H Rashad
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - A Stefanko
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - D Adikaram
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - H Albataineh
- Texas A&M University-Kingsville, Kingsville, Texas 78363, USA
| | - B Aljawrneh
- North Carolina Ag. and Tech. State University, Greensboro, North Carolina 27411, USA
| | - K Allada
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S Allison
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - S Alsalmi
- Kent State University, Kent, Ohio 44240, USA
| | - D Androic
- University of Zagreb, Trg Republike Hrvatske 14, 10000 Zagreb, Croatia
| | - K Aniol
- California State University, Los Angeles, Los Angeles, California 90032, USA
| | - J Annand
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H Atac
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - T Averett
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - C Ayerbe Gayoso
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - X Bai
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - J Bane
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Barcus
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - K Bartlett
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - V Bellini
- Istituto Nazionale di Fisica Nucleare, Dipt. Di Fisica delle Uni. di Catania, I-95123 Catania, Italy
| | | | - J Bericic
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D Biswas
- Hampton University, Hampton, Virginia 23669, USA
| | - E Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | - D Bulumulla
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - J Campbell
- Dalhousie University, Nova Scotia B3H 4R2, Canada
| | - A Camsonne
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Carmignotto
- Catholic University of America, Washington, DC 20064, USA
| | - J Castellano
- Florida International University, Miami, Florida 33199, USA
| | - C Chen
- Hampton University, Hampton, Virginia 23669, USA
| | - J-P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Chetry
- Ohio University, Athens, Ohio 45701, USA
| | - M E Christy
- Hampton University, Hampton, Virginia 23669, USA
| | - E Cisbani
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, P.le Aldo Moro, 2-00185 Roma, Italy
| | - B Clary
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - E Cohen
- Tel Aviv University, Tel Aviv 699780 1, Israel
| | - N Compton
- Ohio University, Athens, Ohio 45701, USA
| | - J C Cornejo
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - S Covrig Dusa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - B Crowe
- North Carolina Central University, Durham, North Carolina 27707, USA
| | - S Danagoulian
- North Carolina Ag. and Tech. State University, Greensboro, North Carolina 27411, USA
| | - T Danley
- Ohio University, Athens, Ohio 45701, USA
| | - F De Persio
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, P.le Aldo Moro, 2-00185 Roma, Italy
| | - W Deconinck
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - M Defurne
- CEA Saclay, 91191 Gif-sur-Yvette, France
| | - C Desnault
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - D Di
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - M Duer
- Tel Aviv University, Tel Aviv 699780 1, Israel
| | - B Duran
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Fanelli
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - G Franklin
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - E Fuchey
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - C Gal
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Gautam
- Hampton University, Hampton, Virginia 23669, USA
| | - O Glamazdin
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - K Gnanvo
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - V M Gray
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - C Gu
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - T Hague
- Kent State University, Kent, Ohio 44240, USA
| | - G Hamad
- Ohio University, Athens, Ohio 45701, USA
| | - D Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - K Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Hauenstein
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - W Henry
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - D W Higinbotham
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Holmstrom
- Randolph Macon College, Ashlan, Virginia 23005, USA
| | - T Horn
- Catholic University of America, Washington, DC 20064, USA
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Y Huang
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - C Hyde
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - H Ibrahim
- Cairo University, Cairo 121613, Egypt
| | - C-M Jen
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 234061, USA
| | - K Jin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - M Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Kabir
- Kent State University, Kent, Ohio 44240, USA
| | - C Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Khachatryan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- Stony Brook, State University of New York, New York 11794, USA
- Cornell University, Ithaca, New York 14853, USA
| | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - S Li
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W Li
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - J Liu
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - H Liu
- Columbia University, New York, New York 10027, USA
| | - A Liyanage
- Hampton University, Hampton, Virginia 23669, USA
| | - J Magee
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - S Malace
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Mammei
- University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - P Markowitz
- Florida International University, Miami, Florida 33199, USA
| | - E McClellan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Meddi
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, P.le Aldo Moro, 2-00185 Roma, Italy
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Mesik
- Rutgers University, New Brunswick, New Jersey 08854, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Mkrtchyan
- Catholic University of America, Washington, DC 20064, USA
| | - R Montgomery
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - C Muñoz Camacho
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - L S Myers
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P Nadel-Turonski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S J Nazeer
- Hampton University, Hampton, Virginia 23669, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - D Nguyen
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - N Nuruzzaman
- Hampton University, Hampton, Virginia 23669, USA
| | - M Nycz
- Kent State University, Kent, Ohio 44240, USA
| | - O F Obretch
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - L Ou
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C Palatchi
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - B Pandey
- Hampton University, Hampton, Virginia 23669, USA
| | - S Park
- Stony Brook, State University of New York, New York 11794, USA
| | - K Park
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - C Peng
- Duke University, Durham, North Carolina 27708, USA
| | - R Pomatsalyuk
- Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine
| | - E Pooser
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A J R Puckett
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - B Quinn
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - S Rahman
- University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - P E Reimer
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - J Roche
- Ohio University, Athens, Ohio 45701, USA
| | - I Sapkota
- Catholic University of America, Washington, DC 20064, USA
| | - A Sarty
- Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N H Saylor
- Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - B Schmookler
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M H Shabestari
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - A Shahinyan
- AANL, 2 Alikhanian Brothers Street, 0036 Yerevan, Armenia
| | - S Sirca
- Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - N Sparveris
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Spies
- University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - T Su
- Kent State University, Kent, Ohio 44240, USA
| | - A Subedi
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - V Sulkosky
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A Sun
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - L Thorne
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Y Tian
- Shandong University, Jinan, Shandong, 250100, China
| | - N Ton
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - F Tortorici
- Istituto Nazionale di Fisica Nucleare, Dipt. Di Fisica delle Uni. di Catania, I-95123 Catania, Italy
| | - R Trotta
- Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA
| | - G M Urciuoli
- Istituto Nazionale di Fisica Nucleare-Sezione di Roma, P.le Aldo Moro, 2-00185 Roma, Italy
| | - E Voutier
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France
| | - B Waidyawansa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Y Wang
- The College of William and Mary, Williamsburg, Virginia 23185, USA
| | - B Wojtsekhowski
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - X Yan
- Huangshan University, Huangshan, Anhui, 245041, China
| | - L Ye
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - Z Ye
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - C Yero
- Florida International University, Miami, Florida 33199, USA
| | - J Zhang
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - Y Zhao
- Stony Brook, State University of New York, New York 11794, USA
| | - P Zhu
- University of Science and Technology of China, Hefei, Anhui 230026, China
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6
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Bhetuwal D, Matter J, Szumila-Vance H, Kabir ML, Dutta D, Ent R, Abrams D, Ahmed Z, Aljawrneh B, Alsalmi S, Ambrose R, Androic D, Armstrong W, Asaturyan A, Assumin-Gyimah K, Ayerbe Gayoso C, Bandari A, Basnet S, Berdnikov V, Bhatt H, Biswas D, Boeglin WU, Bosted P, Brash E, Bukhari MHS, Chen H, Chen JP, Chen M, Christy EM, Covrig S, Craycraft K, Danagoulian S, Day D, Diefenthaler M, Dlamini M, Dunne J, Duran B, Evans R, Fenker H, Fomin N, Fuchey E, Gaskell D, Gautam TN, Gonzalez FA, Hansen JO, Hauenstein F, Hernandez AV, Horn T, Huber GM, Jones MK, Joosten S, Karki A, Keppel C, Khanal A, King PM, Kinney E, Ko HS, Kohl M, Lashley-Colthirst N, Li S, Li WB, Liyanage AH, Mack D, Malace S, Markowitz P, Meekins D, Michaels R, Mkrtchyan A, Mkrtchyan H, Nazeer SJ, Nanda S, Niculescu G, Niculescu I, Nguyen D, Pandey B, Park S, Pooser E, Puckett A, Rehfuss M, Reinhold J, Santiesteban N, Sawatzky B, Smith GR, Sun A, Tadevosyan V, Trotta R, Wood SA, Yero C, Zhang J. Ruling out Color Transparency in Quasielastic ^{12}C(e,e^{'}p) up to Q^{2} of 14.2 (GeV/c)^{2}. Phys Rev Lett 2021; 126:082301. [PMID: 33709760 DOI: 10.1103/physrevlett.126.082301] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/15/2020] [Accepted: 01/14/2021] [Indexed: 06/12/2023]
Abstract
Quasielastic ^{12}C(e,e^{'}p) scattering was measured at spacelike 4-momentum transfer squared Q^{2}=8, 9.4, 11.4, and 14.2 (GeV/c)^{2}, the highest ever achieved to date. Nuclear transparency for this reaction was extracted by comparing the measured yield to that expected from a plane-wave impulse approximation calculation without any final state interactions. The measured transparency was consistent with no Q^{2} dependence, up to proton momenta of 8.5 GeV/c, ruling out the quantum chromodynamics effect of color transparency at the measured Q^{2} scales in exclusive (e,e^{'}p) reactions. These results impose strict constraints on models of color transparency for protons.
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Affiliation(s)
- D Bhetuwal
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - J Matter
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - H Szumila-Vance
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M L Kabir
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Dutta
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D Abrams
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - B Aljawrneh
- North Carolina A & T State University, Greensboro, North Carolina 27411, USA
| | - S Alsalmi
- Kent State University, Kent, Ohio 44240, USA
| | - R Ambrose
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - D Androic
- University of Zagreb, Zagreb, Croatia
| | - W Armstrong
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - A Asaturyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - K Assumin-Gyimah
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - C Ayerbe Gayoso
- Mississippi State University, Mississippi State, Mississippi 39762, USA
- The College of William & Mary, Williamsburg, Virginia 23185, USA
| | - A Bandari
- The College of William & Mary, Williamsburg, Virginia 23185, USA
| | - S Basnet
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - V Berdnikov
- Catholic University of America, Washington, DC 20064, USA
| | - H Bhatt
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Biswas
- Hampton University, Hampton, Virginia 23669, USA
| | - W U Boeglin
- Florida International University, University Park, Florida 33199, USA
| | - P Bosted
- The College of William & Mary, Williamsburg, Virginia 23185, USA
| | - E Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | | | - H Chen
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - J P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Chen
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - E M Christy
- Hampton University, Hampton, Virginia 23669, USA
| | - S Covrig
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Craycraft
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Danagoulian
- North Carolina A & T State University, Greensboro, North Carolina 27411, USA
| | - D Day
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - M Diefenthaler
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Dlamini
- Ohio University, Athens, Ohio 45701, USA
| | - J Dunne
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - B Duran
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Evans
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - H Fenker
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N Fomin
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - E Fuchey
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T N Gautam
- Hampton University, Hampton, Virginia 23669, USA
| | - F A Gonzalez
- Stony Brook University, Stony Brook, New York 11794, USA
| | - J O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Hauenstein
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - A V Hernandez
- Catholic University of America, Washington, DC 20064, USA
| | - T Horn
- Catholic University of America, Washington, DC 20064, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - M K Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Joosten
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - A Karki
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - C Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Khanal
- Florida International University, University Park, Florida 33199, USA
| | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - E Kinney
- University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - H S Ko
- Institut de Physique Nucleaire, Orsay, France
| | - M Kohl
- Hampton University, Hampton, Virginia 23669, USA
| | | | - S Li
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W B Li
- The College of William & Mary, Williamsburg, Virginia 23185, USA
| | - A H Liyanage
- Hampton University, Hampton, Virginia 23669, USA
| | - D Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Malace
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P Markowitz
- Florida International University, University Park, Florida 33199, USA
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Mkrtchyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - H Mkrtchyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - S J Nazeer
- Hampton University, Hampton, Virginia 23669, USA
| | - S Nanda
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - G Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | - I Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | - D Nguyen
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - B Pandey
- Hampton University, Hampton, Virginia 23669, USA
| | - S Park
- Stony Brook University, Stony Brook, New York 11794, USA
| | - E Pooser
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Puckett
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - M Rehfuss
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - J Reinhold
- Florida International University, University Park, Florida 33199, USA
| | - N Santiesteban
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Sun
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - V Tadevosyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - R Trotta
- Catholic University of America, Washington, DC 20064, USA
| | - S A Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Yero
- Florida International University, University Park, Florida 33199, USA
| | - J Zhang
- Stony Brook University, Stony Brook, New York 11794, USA
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7
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Yero C, Abrams D, Ahmed Z, Ahmidouch A, Aljawrneh B, Alsalmi S, Ambrose R, Armstrong W, Asaturyan A, Assumin-Gyimah K, Ayerbe Gayoso C, Bandari A, Bane J, Basnet S, Berdnikov VV, Bericic J, Bhatt H, Bhetuwal D, Biswas D, Boeglin WU, Bosted P, Brash E, Bukhari MHS, Chen H, Chen JP, Chen M, Christy ME, Covrig S, Craycraft K, Danagoulian S, Day D, Diefenthaler M, Dlamini M, Dunne J, Duran B, Dutta D, Ent R, Evans R, Fenker H, Fomin N, Fuchey E, Gaskell D, Gautam TN, Gonzalez FA, Hansen JO, Hauenstein F, Hernandez AV, Horn T, Huber GM, Jones MK, Joosten S, Kabir ML, Karki A, Keppel CE, Khanal A, King P, Kinney E, Lashley-Colthirst N, Li S, Li WB, Liyanage AH, Mack DJ, Malace SP, Matter J, Meekins D, Michaels R, Mkrtchyan A, Mkrtchyan H, Nazeer SJ, Nanda S, Niculescu G, Niculescu M, Nguyen D, Nuruzzaman N, Pandey B, Park S, Perdrisat CF, Pooser E, Rehfuss M, Reinhold J, Sawatzky B, Smith GR, Sun A, Szumila-Vance H, Tadevosyan V, Wood SA, Zhang J. Probing the Deuteron at Very Large Internal Momenta. Phys Rev Lett 2020; 125:262501. [PMID: 33449750 DOI: 10.1103/physrevlett.125.262501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/27/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
We measure ^{2}H(e,e^{'}p)n cross sections at 4-momentum transfers of Q^{2}=4.5±0.5 (GeV/c)^{2} over a range of neutron recoil momenta p_{r}, reaching up to ∼1.0 GeV/c. We obtain data at fixed neutron recoil angles θ_{nq}=35°, 45°, and 75° with respect to the 3-momentum transfer q[over →]. The new data agree well with previous data, which reached p_{r}∼500 MeV/c. At θ_{nq}=35° and 45°, final state interactions, meson exchange currents, and isobar currents are suppressed and the plane wave impulse approximation provides the dominant cross section contribution. We compare the new data to recent theoretical calculations, where we observe a significant discrepancy for recoil momenta p_{r}>700 MeV/c.
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Affiliation(s)
- C Yero
- Florida International University, University Park, Florida 33199, USA
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D Abrams
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - A Ahmidouch
- North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, USA
| | - B Aljawrneh
- North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, USA
| | - S Alsalmi
- Kent State University, Kent, Ohio 44240, USA
| | - R Ambrose
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - W Armstrong
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - A Asaturyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), 2 Alikhanian Brothers Street, 0036, Yerevan, Armenia
| | - K Assumin-Gyimah
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - C Ayerbe Gayoso
- College of William & Mary, Williamsburg, Virginia 23185, USA
| | - A Bandari
- College of William & Mary, Williamsburg, Virginia 23185, USA
| | - J Bane
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Basnet
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - V V Berdnikov
- Catholic University of America, Washington, D.C. 20064, USA
| | - J Bericic
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - H Bhatt
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Bhetuwal
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Biswas
- Hampton University, Hampton, Virginia 23669, USA
| | - W U Boeglin
- Florida International University, University Park, Florida 33199, USA
| | - P Bosted
- College of William & Mary, Williamsburg, Virginia 23185, USA
| | - E Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | | | - H Chen
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - J P Chen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Chen
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - M E Christy
- Hampton University, Hampton, Virginia 23669, USA
| | - S Covrig
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Craycraft
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - S Danagoulian
- North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, USA
| | - D Day
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - M Diefenthaler
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Dlamini
- Ohio University, Athens, Ohio 45701, USA
| | - J Dunne
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - B Duran
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - D Dutta
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R Evans
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - H Fenker
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N Fomin
- University of Tennessee, Knoxville, Tennessee 37996, USA
| | - E Fuchey
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T N Gautam
- Hampton University, Hampton, Virginia 23669, USA
| | - F A Gonzalez
- Stony Brook University, Stony Brook, New York 11794, USA
| | - J O Hansen
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Hauenstein
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - A V Hernandez
- Catholic University of America, Washington, D.C. 20064, USA
| | - T Horn
- Catholic University of America, Washington, D.C. 20064, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - M K Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Joosten
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - M L Kabir
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - A Karki
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - C E Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Khanal
- Florida International University, University Park, Florida 33199, USA
| | - P King
- Ohio University, Athens, Ohio 45701, USA
| | - E Kinney
- University of Colorado Boulder, Boulder, Colorado 80309, USA
| | | | - S Li
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W B Li
- College of William & Mary, Williamsburg, Virginia 23185, USA
| | - A H Liyanage
- Hampton University, Hampton, Virginia 23669, USA
| | - D J Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S P Malace
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Matter
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Mkrtchyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), 2 Alikhanian Brothers Street, 0036, Yerevan, Armenia
| | - H Mkrtchyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), 2 Alikhanian Brothers Street, 0036, Yerevan, Armenia
| | - S J Nazeer
- Hampton University, Hampton, Virginia 23669, USA
| | - S Nanda
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - G Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | - M Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | - D Nguyen
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - N Nuruzzaman
- Rutgers University, New Brunswick, New Jersey 08854, USA
| | - B Pandey
- Hampton University, Hampton, Virginia 23669, USA
| | - S Park
- Stony Brook University, Stony Brook, New York 11794, USA
| | - C F Perdrisat
- College of William & Mary, Williamsburg, Virginia 23185, USA
| | - E Pooser
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M Rehfuss
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - J Reinhold
- Florida International University, University Park, Florida 33199, USA
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Sun
- Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - H Szumila-Vance
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Tadevosyan
- A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), 2 Alikhanian Brothers Street, 0036, Yerevan, Armenia
| | - S A Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Zhang
- Stony Brook University, Stony Brook, New York 11794, USA
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8
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Androić D, Armstrong DS, Asaturyan A, Bartlett K, Beaufait J, Beminiwattha RS, Benesch J, Benmokhtar F, Birchall J, Carlini RD, Cornejo JC, Dusa SC, Dalton MM, Davis CA, Deconinck W, Dowd JF, Dunne JA, Dutta D, Duvall WS, Elaasar M, Falk WR, Finn JM, Forest T, Gal C, Gaskell D, Gericke MTW, Grames J, Gray VM, Grimm K, Guo F, Hoskins JR, Jones D, Jones MK, Jones RT, Kargiantoulakis M, King PM, Korkmaz E, Kowalski S, Leacock J, Leckey JP, Lee AR, Lee JH, Lee L, MacEwan S, Mack D, Magee JA, Mahurin R, Mammei J, Martin JW, McHugh MJ, Meekins D, Mei J, Mesick KE, Michaels R, Micherdzinska A, Mkrtchyan A, Mkrtchyan H, Morgan N, Narayan A, Ndukum LZ, Nelyubin V, van Oers WTH, Owen VF, Page SA, Pan J, Paschke KD, Phillips SK, Pitt ML, Radloff RW, Rajotte JF, Ramsay WD, Roche J, Sawatzky B, Seva T, Shabestari MH, Silwal R, Simicevic N, Smith GR, Solvignon P, Spayde DT, Subedi A, Subedi R, Suleiman R, Tadevosyan V, Tobias WA, Tvaskis V, Waidyawansa B, Wang P, Wells SP, Wood SA, Yang S, Zang P, Zhamkochyan S. Precision Measurement of the Beam-Normal Single-Spin Asymmetry in Forward-Angle Elastic Electron-Proton Scattering. Phys Rev Lett 2020; 125:112502. [PMID: 32976004 DOI: 10.1103/physrevlett.125.112502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/07/2020] [Accepted: 08/11/2020] [Indexed: 06/11/2023]
Abstract
A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.
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Affiliation(s)
- D Androić
- University of Zagreb, Zagreb, HR 10002, Croatia
| | | | - A Asaturyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - K Bartlett
- William & Mary, Williamsburg, Virginia 23185, USA
| | - J Beaufait
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R S Beminiwattha
- Ohio University, Athens, Ohio 45701, USA
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - J Benesch
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - F Benmokhtar
- Duquesne University, Pittburgh, Pennsylvania 15282, USA
| | - J Birchall
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - R D Carlini
- William & Mary, Williamsburg, Virginia 23185, USA
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J C Cornejo
- William & Mary, Williamsburg, Virginia 23185, USA
| | - S Covrig Dusa
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M M Dalton
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - C A Davis
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - W Deconinck
- William & Mary, Williamsburg, Virginia 23185, USA
| | - J F Dowd
- William & Mary, Williamsburg, Virginia 23185, USA
| | - J A Dunne
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Dutta
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - W S Duvall
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA
| | - M Elaasar
- Southern University at New Orleans, New Orleans, Louisiana 70126, USA
| | - W R Falk
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J M Finn
- William & Mary, Williamsburg, Virginia 23185, USA
| | - T Forest
- Louisiana Tech University, Ruston, Louisiana 71272, USA
- Idaho State University, Pocatello, Idaho 83209, USA
| | - C Gal
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - M T W Gericke
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J Grames
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V M Gray
- William & Mary, Williamsburg, Virginia 23185, USA
| | - K Grimm
- William & Mary, Williamsburg, Virginia 23185, USA
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - F Guo
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J R Hoskins
- William & Mary, Williamsburg, Virginia 23185, USA
| | - D Jones
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - M K Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - R T Jones
- University of Connecticut, Storrs-Mansfield, Connecticut 06269, USA
| | | | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - E Korkmaz
- University of Northern British Columbia, Prince George, British Columbia V2N4Z9, Canada
| | - S Kowalski
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - J Leacock
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA
| | - J P Leckey
- William & Mary, Williamsburg, Virginia 23185, USA
| | - A R Lee
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA
| | - J H Lee
- William & Mary, Williamsburg, Virginia 23185, USA
- Ohio University, Athens, Ohio 45701, USA
| | - L Lee
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - S MacEwan
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - D Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J A Magee
- William & Mary, Williamsburg, Virginia 23185, USA
| | - R Mahurin
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J Mammei
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA
| | - J W Martin
- University of Winnipeg, Winnipeg, Manitoba R3B2E9, Canada
| | - M J McHugh
- George Washington University, Washington, DC 20052, USA
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Mei
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K E Mesick
- George Washington University, Washington, DC 20052, USA
- Rutgers, The State University of New Jersey, Piscataway, New Jersey 088754, USA
| | - R Michaels
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - A Mkrtchyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - H Mkrtchyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - N Morgan
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA
| | - A Narayan
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - L Z Ndukum
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - V Nelyubin
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - W T H van Oers
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - V F Owen
- William & Mary, Williamsburg, Virginia 23185, USA
| | - S A Page
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - J Pan
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - K D Paschke
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - S K Phillips
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - M L Pitt
- Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA
| | | | - J F Rajotte
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - W D Ramsay
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - J Roche
- Ohio University, Athens, Ohio 45701, USA
| | - B Sawatzky
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Seva
- University of Zagreb, Zagreb, HR 10002, Croatia
| | - M H Shabestari
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Silwal
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - N Simicevic
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P Solvignon
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D T Spayde
- Hendrix College, Conway, Arkansas 72032, USA
| | - A Subedi
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Subedi
- George Washington University, Washington, DC 20052, USA
| | - R Suleiman
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Tadevosyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
| | - W A Tobias
- University of Virginia, Charlottesville, Virginia 22903, USA
| | - V Tvaskis
- University of Winnipeg, Winnipeg, Manitoba R3B2E9, Canada
| | - B Waidyawansa
- Ohio University, Athens, Ohio 45701, USA
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - P Wang
- University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
| | - S P Wells
- Louisiana Tech University, Ruston, Louisiana 71272, USA
| | - S A Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Yang
- William & Mary, Williamsburg, Virginia 23185, USA
| | - P Zang
- Syracuse University, Syracuse, New York 13244, USA
| | - S Zhamkochyan
- A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan 0036, Armenia
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9
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Smith GR, Crowther TW, Eisenhauer N, van den Hoogen J. Building a global database of soil microbial biomass and function: a call for collaboration. Soil Org 2020; 91:139-142. [PMID: 32577136 PMCID: PMC7311196 DOI: 10.25674/so91iss3pp140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Global analyses are emerging as valuable complements to local and regional scale studies in ecology and are useful for examining many of the major environmental issues that we face today. Soil ecology has significantly benefited from these developments, with recent syntheses unearthing interesting, unexpected biogeographic patterns in belowground biotic communities. However, some questions still remain unanswered, and the accuracy of these studies is inevitably limited by the extent of the data they draw upon. This is a particular problem in global ecology because most datasets used exhibit geographic bias in sample distribution. Here, we work towards addressing this problem with an open call for collaboration on a planned global analysis of soil phospholipid fatty acid and potential enzyme activity measurements. We summarize the current extent of our dataset, outline the planned analyses, and provide information for prospective collaborators who would like to contribute or learn more.
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Affiliation(s)
- Gabriel R. Smith
- Department of Biology, Stanford University, 371 Jane Stanford Way, Stanford, CA 94305, USA
- Global Ecosystem Ecology, Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, 8092 Zürich, Switzerland
| | - Thomas W. Crowther
- Global Ecosystem Ecology, Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, 8092 Zürich, Switzerland
| | - Nico Eisenhauer
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany
- Leipzig University, Institute of Biology, Deutscher Platz 5e, 04103 Leipzig, Germany
| | - Johan van den Hoogen
- Global Ecosystem Ecology, Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, 8092 Zürich, Switzerland
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10
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Affiliation(s)
- Gabriel R Smith
- Department of Biology, Stanford University, 371 Jane Stanford Way, Stanford, CA, 94305, USA
- Global Ecosystem Ecology, Department of Environmental Systems Science, Institute of Integrative Biology, ETH Zürich, 8092, Zürich, Switzerland
| | - Kabir G Peay
- Department of Biology, Stanford University, 371 Jane Stanford Way, Stanford, CA, 94305, USA
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11
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Li WB, Huber GM, Blok HP, Gaskell D, Horn T, Semenov-Tian-Shansky K, Pire B, Szymanowski L, Laget JM, Aniol K, Arrington J, Beise EJ, Boeglin W, Brash EJ, Breuer H, Chang CC, Christy ME, Ent R, Gibson EF, Holt RJ, Jin S, Jones MK, Keppel CE, Kim W, King PM, Kovaltchouk V, Liu J, Lolos GJ, Mack DJ, Margaziotis DJ, Markowitz P, Matsumura A, Meekins D, Miyoshi T, Mkrtchyan H, Niculescu I, Okayasu Y, Pentchev L, Perdrisat C, Potterveld D, Punjabi V, Reimer PE, Reinhold J, Roche J, Roos PG, Sarty A, Smith GR, Tadevosyan V, Tang LG, Tvaskis V, Volmer J, Vulcan W, Warren G, Wood SA, Xu C, Zheng X. Unique Access to u-Channel Physics: Exclusive Backward-Angle Omega Meson Electroproduction. Phys Rev Lett 2019; 123:182501. [PMID: 31763910 DOI: 10.1103/physrevlett.123.182501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 10/01/2019] [Indexed: 06/10/2023]
Abstract
Backward-angle meson electroproduction above the resonance region, which was previously ignored, is anticipated to offer unique access to the three quark plus sea component of the nucleon wave function. In this Letter, we present the first complete separation of the four electromagnetic structure functions above the resonance region in exclusive ω electroproduction off the proton, ep→e^{'}pω, at central Q^{2} values of 1.60, 2.45 GeV^{2}, at W=2.21 GeV. The results of our pioneering -u≈-u_{min} study demonstrate the existence of a unanticipated backward-angle cross section peak and the feasibility of full L/T/LT/TT separations in this never explored kinematic territory. At Q^{2}=2.45 GeV^{2}, the observed dominance of σ_{T} over σ_{L}, is qualitatively consistent with the collinear QCD description in the near-backward regime, in which the scattering amplitude factorizes into a hard subprocess amplitude and baryon to meson transition distribution amplitudes: universal nonperturbative objects only accessible through backward-angle kinematics.
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Affiliation(s)
- W B Li
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- College of William and Mary, Williamsburg, Virginia 23185, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - H P Blok
- VU University, NL-1081 HV Amsterdam, Netherlands
- NIKHEF, Postbus 41882, NL-1009 DB Amsterdam, Netherlands
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Horn
- Catholic University of America, Washington, D.C. 20064, USA
| | - K Semenov-Tian-Shansky
- National Research Centre Kurchatov Institute: Petersburg Nuclear Physics Institute, RU-188300 Gatchina, Russia
- Saint Petersburg National Research Academic University of the Russian Academy of Sciences, RU-194021 St. Petersburg, Russia
| | - B Pire
- CPHT, CNRS, École Polytechnique, IP Paris, 91128-Palaiseau, France
| | - L Szymanowski
- National Centre for Nuclear Research (NCBJ), 02-093 Warsaw, Poland
| | - J-M Laget
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Aniol
- California State University Los Angeles, Los Angeles, California 90032, USA
| | - J Arrington
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - E J Beise
- University of Maryland, College Park, Maryland 20742, USA
| | - W Boeglin
- Florida International University, Miami, Florida 33119, USA
| | - E J Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | - H Breuer
- University of Maryland, College Park, Maryland 20742, USA
| | - C C Chang
- University of Maryland, College Park, Maryland 20742, USA
| | - M E Christy
- Hampton University, Hampton, Virginia 23668, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - E F Gibson
- California State University, Sacramento, California 95819, USA
| | - R J Holt
- Caltech, Pasadena, California 91125, USA
| | - S Jin
- Kyungpook National University, Daegu, 702-701, Republic of Korea
| | - M K Jones
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C E Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- Hampton University, Hampton, Virginia 23668, USA
| | - W Kim
- Kyungpook National University, Daegu, 702-701, Republic of Korea
| | - P M King
- Ohio University, Athens, Ohio 45701, USA
| | - V Kovaltchouk
- Ontario Tech University, Oshawa, Ontario L1G 0C5, Canada
| | - J Liu
- Shanghai Jiao Tong University, Shanghai 200240, China
| | - G J Lolos
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - D J Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D J Margaziotis
- California State University Los Angeles, Los Angeles, California 90032, USA
| | - P Markowitz
- Florida International University, Miami, Florida 33119, USA
| | - A Matsumura
- Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Miyoshi
- Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - H Mkrtchyan
- A.I. Alikhanyan National Science Laboratory, Yerevan 0036, Armenia
| | - I Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | - Y Okayasu
- Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - L Pentchev
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Perdrisat
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - D Potterveld
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - P E Reimer
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - J Reinhold
- Florida International University, Miami, Florida 33119, USA
| | - J Roche
- Ohio University, Athens, Ohio 45701, USA
| | - P G Roos
- University of Maryland, College Park, Maryland 20742, USA
| | - A Sarty
- Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - V Tadevosyan
- A.I. Alikhanyan National Science Laboratory, Yerevan 0036, Armenia
| | - L G Tang
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
- Hampton University, Hampton, Virginia 23668, USA
| | - V Tvaskis
- NIKHEF, Postbus 41882, NL-1009 DB Amsterdam, Netherlands
- VU University, NL-1081 HV Amsterdam, Netherlands
| | - J Volmer
- VU University, NL-1081 HV Amsterdam, Netherlands
- DESY, Hamburg 22607, Germany
| | - W Vulcan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - G Warren
- Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - S A Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Xu
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - X Zheng
- University of Virginia, Charlottesville, Virginia 22904, USA
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12
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Buchkowski RW, Shaw AN, Sihi D, Smith GR, Keiser AD. Constraining Carbon and Nutrient Flows in Soil With Ecological Stoichiometry. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00382] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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13
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Smith GR, Wan J. Resource-ratio theory predicts mycorrhizal control of litter decomposition. New Phytol 2019; 223:1595-1606. [PMID: 31066058 DOI: 10.1111/nph.15884] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 02/24/2019] [Indexed: 05/27/2023]
Abstract
Ecosystems with ectomycorrhizal plants have high soil carbon : nitrogen ratios, but it is not clear why. The Gadgil effect, where competition between ectomycorrhizal and saprotrophic fungi for nitrogen slows litter decomposition, may increase soil carbon. However, experimental evidence for the Gadgil effect is equivocal. Here, we apply resource-ratio theory to assess whether interguild fungal competition for different forms of organic nitrogen can affect litter decomposition. We focus on variation in resource input ratios and fungal resource use traits, and evaluate our model's predictions by synthesizing prior experimental literature examining ectomycorrhizal effects on litter decomposition. In our model, resource input ratios determined whether ectomycorrhizal fungi suppressed saprotrophic fungi. Recalcitrant litter inputs favored the former over the latter, allowing the Gadgil effect only when such inputs predominated. Although ectomycorrhizal fungi did not always hamper litter decomposition, ectomycorrhizal nitrogen uptake always increased carbon : nitrogen ratios in litter. Our meta-analysis of empirical studies supports our theoretical results: ectomycorrhizal fungi appear to slow decomposition of leaf litter only in forests where litter inputs are highly recalcitrant. We thus find that the specific contribution of the Gadgil effect to high soil carbon : nitrogen ratios in ectomycorrhizal ecosystems may be smaller than predicted previously.
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Affiliation(s)
- Gabriel R Smith
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA, USA
| | - Joe Wan
- Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland
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14
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Albayrak I, Mamyan V, Christy ME, Ahmidouch A, Arrington J, Asaturyan A, Bodek A, Bosted P, Bradford R, Brash E, Bruell A, Butuceanu C, Coleman SJ, Commisso M, Connell SH, Dalton MM, Danagoulian S, Daniel A, Day DB, Dhamija S, Dunne J, Dutta D, Ent R, Gaskell D, Gasparian A, Gran R, Horn T, Huang L, Huber GM, Jayalath C, Johnson M, Jones MK, Kalantarians N, Liyanage A, Keppel CE, Kinney E, Li Y, Malace S, Manly S, Markowitz P, Maxwell J, Mbianda NN, McFarland KS, Meziane M, Meziani ZE, Mills GB, Mkrtchyan H, Mkrtchyan A, Mulholland J, Nelson J, Niculescu G, Niculescu I, Pentchev L, Puckett A, Punjabi V, Qattan IA, Reimer PE, Reinhold J, Rodriguez VM, Rondon-Aramayo O, Sakuda M, Sakumoto WK, Segbefia E, Seva T, Sick I, Slifer K, Smith GR, Steinman J, Solvignon P, Tadevosyan V, Tajima S, Tvaskis V, Vulcan WF, Walton T, Wesselmann FR, Wood SA, Ye Z. Measurements of Nonsinglet Moments of the Nucleon Structure Functions and Comparison to Predictions from Lattice QCD for Q^{2}=4 GeV^{2}. Phys Rev Lett 2019; 123:022501. [PMID: 31386522 DOI: 10.1103/physrevlett.123.022501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 04/10/2019] [Indexed: 06/10/2023]
Abstract
We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.
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Affiliation(s)
- I Albayrak
- Hampton University, Hampton, Virginia 23668, USA
- Catholic University of America, Washington, DC 20064, USA
| | - V Mamyan
- University of Chicago, Chicago, Illinois 60637, USA
| | - M E Christy
- Hampton University, Hampton, Virginia 23668, USA
| | - A Ahmidouch
- North Carolina A&T State University, Greensboro, North Carolina 27411, USA
| | - J Arrington
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - A Asaturyan
- Yerevan Physics Institute, Yerevan 0036, Armenia
| | - A Bodek
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
| | - P Bosted
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - R Bradford
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - E Brash
- Christopher Newport University, Newport News, Virginia 23606, USA
| | - A Bruell
- DFG, German Research Foundation, Bonn 51170, Germany
| | - C Butuceanu
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - S J Coleman
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - M Commisso
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - S H Connell
- University of Johannesburg, Auckland Park 2006, Johannesburg, South Africa
| | - M M Dalton
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - S Danagoulian
- North Carolina A&T State University, Greensboro, North Carolina 27411, USA
| | - A Daniel
- University of Houston, Houston, Texas 77004, USA
| | - D B Day
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - S Dhamija
- Florida International University, Miami, Florida 33199, USA
| | - J Dunne
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - D Dutta
- Mississippi State University, Mississippi State, Mississippi 39762, USA
| | - R Ent
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D Gaskell
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - A Gasparian
- North Carolina A&T State University, Greensboro, North Carolina 27411, USA
| | - R Gran
- Department of Physics, University of Minnesota-Duluth, Duluth, Minnesota 55812, USA
| | - T Horn
- Catholic University of America, Washington, DC 20064, USA
| | - Liting Huang
- Hampton University, Hampton, Virginia 23668, USA
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - C Jayalath
- Hampton University, Hampton, Virginia 23668, USA
| | - M Johnson
- Argonne National Laboratory, Argonne, Illinois 60439, USA
- Northwestern University, Evanston, Illinois 60208, USA
| | - M K Jones
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - N Kalantarians
- Virginia Union University, Richmond, Virginia 23220, USA
| | - A Liyanage
- Hampton University, Hampton, Virginia 23668, USA
| | - C E Keppel
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - E Kinney
- University of Colorado, Boulder, Colorado 80309, USA
| | - Y Li
- Hampton University, Hampton, Virginia 23668, USA
| | - S Malace
- Duke University, Department of Physics, Box 90305, Durham, North Carolina 27708
| | - S Manly
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
| | - P Markowitz
- Florida International University, Miami, Florida 33199, USA
| | - J Maxwell
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - N N Mbianda
- University of Johannesburg, Auckland Park 2006, Johannesburg, South Africa
| | - K S McFarland
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
| | - M Meziane
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - Z E Meziani
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - G B Mills
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - H Mkrtchyan
- Yerevan Physics Institute, Yerevan 0036, Armenia
| | - A Mkrtchyan
- Yerevan Physics Institute, Yerevan 0036, Armenia
| | - J Mulholland
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - J Nelson
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - G Niculescu
- James Madison University, Harrisonburg, Virginia 22801, USA
| | - I Niculescu
- James Madison University, Harrisonburg, Virginia 22801, USA
| | - L Pentchev
- Department of Physics, College of William & Mary, Williamsburg, Virginia 23187, USA
| | - A Puckett
- University of Connecticut, Storrs, Connecticut 06269, USA
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - I A Qattan
- Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates
| | - P E Reimer
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - J Reinhold
- Florida International University, Miami, Florida 33199, USA
| | | | | | - M Sakuda
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - W K Sakumoto
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
| | - E Segbefia
- Hampton University, Hampton, Virginia 23668, USA
| | - T Seva
- University of Zagreb, Zagreb 10000, Croatia
| | - I Sick
- University of Basel, CH-4056 Basel, Switzerland
| | - K Slifer
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - G R Smith
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Steinman
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA
| | - P Solvignon
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - V Tadevosyan
- Yerevan Physics Institute, Yerevan 0036, Armenia
| | - S Tajima
- University of Virginia, Charlottesville, Virginia 22904, USA
| | - V Tvaskis
- University of Winnipeg, Winnipeg, Manitoba R3B 2E9, Canada
| | - W F Vulcan
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Walton
- Hampton University, Hampton, Virginia 23668, USA
| | | | - S A Wood
- Thomas Jeferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - Zhihong Ye
- Hampton University, Hampton, Virginia 23668, USA
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15
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Smith GR, Steidinger BS, Bruns TD, Peay KG. Competition-colonization tradeoffs structure fungal diversity. ISME J 2018; 12:1758-1767. [PMID: 29491493 PMCID: PMC6018791 DOI: 10.1038/s41396-018-0086-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 01/28/2018] [Accepted: 02/07/2018] [Indexed: 01/13/2023]
Abstract
Findings of immense microbial diversity are at odds with observed functional redundancy, as competitive exclusion should hinder coexistence. Tradeoffs between dispersal and competitive ability could resolve this contradiction, but the extent to which they influence microbial community assembly is unclear. Because fungi influence the biogeochemical cycles upon which life on earth depends, understanding the mechanisms that maintain the richness of their communities is critically important. Here, we focus on ectomycorrhizal fungi, which are microbial plant mutualists that significantly affect global carbon dynamics and the ecology of host plants. Synthesizing theory with a decade of empirical research at our study site, we show that competition-colonization tradeoffs structure diversity in situ and that models calibrated only with empirically derived competition-colonization tradeoffs can accurately predict species-area relationships in this group of key eukaryotic microbes. These findings provide evidence that competition-colonization tradeoffs can sustain the landscape-scale diversity of microbes that compete for a single limiting resource.
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Affiliation(s)
- Gabriel R Smith
- Department of Biology, Stanford University, Stanford, CA, 94305, USA.
| | | | - Thomas D Bruns
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
| | - Kabir G Peay
- Department of Biology, Stanford University, Stanford, CA, 94305, USA.
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16
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Smith GR, Finlay RD, Stenlid J, Vasaitis R, Menkis A. Growing evidence for facultative biotrophy in saprotrophic fungi: data from microcosm tests with 201 species of wood-decay basidiomycetes. New Phytol 2017; 215:747-755. [PMID: 28382741 DOI: 10.1111/nph.14551] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 02/24/2017] [Indexed: 06/07/2023]
Abstract
Ectomycorrhizal (ECM) symbioses have evolved a minimum of 78 times independently from saprotrophic lineages, indicating the potential for functional overlap between ECM and saprotrophic fungi. ECM fungi have the capacity to decompose organic matter, and although there is increasing evidence that some saprotrophic fungi exhibit the capacity to enter into facultative biotrophic relationships with plant roots without causing disease symptoms, this subject is still not well studied. In order to determine the extent of biotrophic capacity in saprotrophic wood-decay fungi and which systems may be useful models, we investigated the colonization of conifer seedling roots in vitro using an array of 201 basidiomycete wood-decay fungi. Microtome sectioning, differential staining and fluorescence microscopy were used to visualize patterns of root colonization in microcosm systems containing Picea abies or Pinus sylvestris seedlings and each saprotrophic fungus. Thirty-four (16.9%) of the tested fungal species colonized the roots of at least one tree species. Two fungal species showed formation of a mantle and one showed Hartig net-like structures. These features suggest the possibility of an active functional symbiosis between fungus and plant. The data indicate that the capacity for facultative biotrophic relationships in free-living saprotrophic basidiomycetes may be greater than previously supposed.
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Affiliation(s)
- Gabriel R Smith
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA, 94305, USA
| | - Roger D Finlay
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, PO Box 7026, Uppsala, SE-75007, Sweden
| | - Jan Stenlid
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, PO Box 7026, Uppsala, SE-75007, Sweden
| | - Rimvydas Vasaitis
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, PO Box 7026, Uppsala, SE-75007, Sweden
| | - Audrius Menkis
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, PO Box 7026, Uppsala, SE-75007, Sweden
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17
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Affiliation(s)
- G R Smith
- Nuffield Institute of Comparative Medicine, Zoological Society of London, Regent's Park, London NW1
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18
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Wilson CL, Jurk D, Fullard N, Banks P, Page A, Luli S, Elsharkawy AM, Gieling RG, Chakraborty JB, Fox C, Richardson C, Callaghan K, Blair GE, Fox N, Lagnado A, Passos JF, Moore AJ, Smith GR, Tiniakos DG, Mann J, Oakley F, Mann DA. NFκB1 is a suppressor of neutrophil-driven hepatocellular carcinoma. Nat Commun 2015; 6:6818. [PMID: 25879839 PMCID: PMC4410629 DOI: 10.1038/ncomms7818] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 03/02/2015] [Indexed: 02/07/2023] Open
Abstract
Hepatocellular carcinoma (HCC) develops on the background of chronic hepatitis.
Leukocytes found within the HCC microenvironment are implicated as regulators of
tumour growth. We show that diethylnitrosamine (DEN)-induced murine HCC is
attenuated by antibody-mediated depletion of hepatic neutrophils, the latter
stimulating hepatocellular ROS and telomere DNA damage. We additionally report a
previously unappreciated tumour suppressor function for hepatocellular nfkb1
operating via p50:p50 dimers and the co-repressor HDAC1. These anti-inflammatory
proteins combine to transcriptionally repress hepatic expression of a S100A8/9,
CXCL1 and CXCL2 neutrophil chemokine network. Loss of nfkb1 promotes
ageing-associated chronic liver disease (CLD), characterized by steatosis,
neutrophillia, fibrosis, hepatocyte telomere damage and HCC.
Nfkb1S340A/S340Amice carrying a mutation
designed to selectively disrupt p50:p50:HDAC1 complexes are more susceptible to HCC;
by contrast, mice lacking S100A9 express reduced neutrophil chemokines and are
protected from HCC. Inhibiting neutrophil accumulation in CLD or targeting their
tumour-promoting activities may offer therapeutic opportunities in HCC. The role of neutrophils in cancer development is not widely
appreciated. Here, the authors show that NF-κB-deficient hepatocytes
overproduce chemokines, leading to hepatocellular carcinoma due to excessive neutrophil
recruitment, and that neutrophil depletion prevents liver cancer in these
mice.
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Affiliation(s)
- C L Wilson
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - D Jurk
- Newcastle University Institute for Ageing and Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne NE4 5PL, UK
| | - N Fullard
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - P Banks
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - A Page
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - S Luli
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - A M Elsharkawy
- Liver Unit, University Hospitals Birmingham, Birmingham B15 2TH, UK
| | - R G Gieling
- Hypoxia and Therapeutics Group, Manchester Pharmacy School, University of Manchester, Manchester M13 9PT, UK
| | - J Bagchi Chakraborty
- Department of Medicine, Immunology and Inflammation, Imperial College of Science, Technology and Medicine, Hammersmith Hospital, London W12 0NN, UK
| | - C Fox
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - C Richardson
- Centre for Behaviour and Evolution/Institute of Neuroscience, Medical School, Newcastle University, Newcastle Upon Tyne NE2 4HH, UK
| | - K Callaghan
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - G E Blair
- Faculty of Biological Sciences, School of Molecular and Cellular Biology, University of Leeds, Garstang Building, Leeds LS2 9JT, UK
| | - N Fox
- Faculty of Biological Sciences, School of Molecular and Cellular Biology, University of Leeds, Garstang Building, Leeds LS2 9JT, UK
| | - A Lagnado
- Newcastle University Institute for Ageing and Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne NE4 5PL, UK
| | - J F Passos
- Newcastle University Institute for Ageing and Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne NE4 5PL, UK
| | - A J Moore
- Institute for Cell and Molecular Biosciences, Newcastle University, Catherine Cookson Building, Framlington Place, Newcastle Upon Tyne NE2 4HH, UK
| | - G R Smith
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - D G Tiniakos
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - J Mann
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - F Oakley
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - D A Mann
- Fibrosis Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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19
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Huber GM, Blok HP, Butuceanu C, Gaskell D, Horn T, Mack DJ, Abbott D, Aniol K, Anklin H, Armstrong C, Arrington J, Assamagan K, Avery S, Baker OK, Barrett B, Beise EJ, Bochna C, Boeglin W, Brash EJ, Breuer H, Chang CC, Chant N, Christy ME, Dunne J, Eden T, Ent R, Fenker H, Gibson EF, Gilman R, Gustafsson K, Hinton W, Holt RJ, Jackson H, Jin S, Jones MK, Keppel CE, Kim PH, Kim W, King PM, Klein A, Koltenuk D, Kovaltchouk V, Liang M, Liu J, Lolos GJ, Lung A, Margaziotis DJ, Markowitz P, Matsumura A, McKee D, Meekins D, Mitchell J, Miyoshi T, Mkrtchyan H, Mueller B, Niculescu G, Niculescu I, Okayasu Y, Pentchev L, Perdrisat C, Pitz D, Potterveld D, Punjabi V, Qin LM, Reimer PE, Reinhold J, Roche J, Roos PG, Sarty A, Shin IK, Smith GR, Stepanyan S, Tang LG, Tadevosyan V, Tvaskis V, van der Meer RLJ, Vansyoc K, Van Westrum D, Vidakovic S, Volmer J, Vulcan W, Warren G, Wood SA, Xu C, Yan C, Zhao WX, Zheng X, Zihlmann B. Separated response function ratios in exclusive, forward π(±) electroproduction. Phys Rev Lett 2014; 112:182501. [PMID: 24856691 DOI: 10.1103/physrevlett.112.182501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Indexed: 06/03/2023]
Abstract
The study of exclusive π(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σL(π-)/σL(π+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σT(π-)/σT(π+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6 GeV(2) at W=1.95 GeV, and Q(2)=2.45 GeV(2) at W=2.22 GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.
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Affiliation(s)
- G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - H P Blok
- VU university, NL-1081 HV Amsterdam, The Netherlands and NIKHEF, Postbus 41882, NL-1009 DB Amsterdam, The Netherlands
| | - C Butuceanu
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - D Gaskell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Horn
- Catholic University of America, Washington, DC 20064, USA
| | - D J Mack
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D Abbott
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - K Aniol
- California State University Los Angeles, Los Angeles, California 90032, USA
| | - H Anklin
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Florida International University, Miami, Florida 33119, USA
| | - C Armstrong
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - J Arrington
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - K Assamagan
- Hampton University, Hampton, Virginia 23668, USA
| | - S Avery
- Hampton University, Hampton, Virginia 23668, USA
| | - O K Baker
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Hampton University, Hampton, Virginia 23668, USA
| | - B Barrett
- Saint Mary's University, Halifax, Nova Scotia B3H 3C3 Canada
| | - E J Beise
- University of Maryland, College Park, Maryland 20742, USA
| | - C Bochna
- University of Illinois, Champaign, Illinois 61801, USA
| | - W Boeglin
- Florida International University, Miami, Florida 33119, USA
| | - E J Brash
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - H Breuer
- University of Maryland, College Park, Maryland 20742, USA
| | - C C Chang
- University of Maryland, College Park, Maryland 20742, USA
| | - N Chant
- University of Maryland, College Park, Maryland 20742, USA
| | - M E Christy
- Hampton University, Hampton, Virginia 23668, USA
| | - J Dunne
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - T Eden
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Norfolk State University, Norfolk, Virginia 23504, USA
| | - R Ent
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - H Fenker
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - E F Gibson
- California State University, Sacramento, California 95819, USA
| | - R Gilman
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - K Gustafsson
- University of Maryland, College Park, Maryland 20742, USA
| | - W Hinton
- Hampton University, Hampton, Virginia 23668, USA
| | - R J Holt
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - H Jackson
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - S Jin
- Kyungpook National University, Daegu 702-701, Republic of Korea
| | - M K Jones
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - C E Keppel
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Hampton University, Hampton, Virginia 23668, USA
| | - P H Kim
- Kyungpook National University, Daegu 702-701, Republic of Korea
| | - W Kim
- Kyungpook National University, Daegu 702-701, Republic of Korea
| | - P M King
- University of Maryland, College Park, Maryland 20742, USA
| | - A Klein
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - D Koltenuk
- University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - V Kovaltchouk
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - M Liang
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Liu
- University of Maryland, College Park, Maryland 20742, USA
| | - G J Lolos
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - A Lung
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - D J Margaziotis
- California State University Los Angeles, Los Angeles, California 90032, USA
| | - P Markowitz
- Florida International University, Miami, Florida 33119, USA
| | | | - D McKee
- New Mexico State University, Las Cruces, New Mexico 88003-8001, USA
| | - D Meekins
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - J Mitchell
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | | | - H Mkrtchyan
- A.I. Alikhanyan National Science Laboratory, Yerevan 0036, Armenia
| | - B Mueller
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - G Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | - I Niculescu
- James Madison University, Harrisonburg, Virginia 22807, USA
| | | | - L Pentchev
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - C Perdrisat
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | - D Pitz
- DAPNIA/SPhN, CEA/Saclay, F-91191 Gif-sur-Yvette, France
| | - D Potterveld
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - V Punjabi
- Norfolk State University, Norfolk, Virginia 23504, USA
| | - L M Qin
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - P E Reimer
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - J Reinhold
- Florida International University, Miami, Florida 33119, USA
| | - J Roche
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - P G Roos
- University of Maryland, College Park, Maryland 20742, USA
| | - A Sarty
- Saint Mary's University, Halifax, Nova Scotia B3H 3C3 Canada
| | - I K Shin
- Kyungpook National University, Daegu 702-701, Republic of Korea
| | - G R Smith
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S Stepanyan
- A.I. Alikhanyan National Science Laboratory, Yerevan 0036, Armenia
| | - L G Tang
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and Hampton University, Hampton, Virginia 23668, USA
| | - V Tadevosyan
- A.I. Alikhanyan National Science Laboratory, Yerevan 0036, Armenia
| | - V Tvaskis
- VU university, NL-1081 HV Amsterdam, The Netherlands and NIKHEF, Postbus 41882, NL-1009 DB Amsterdam, The Netherlands
| | | | - K Vansyoc
- Old Dominion University, Norfolk, Virginia 23529, USA
| | - D Van Westrum
- University of Colorado, Boulder, Colorado 80309, USA
| | - S Vidakovic
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - J Volmer
- VU university, NL-1081 HV Amsterdam, The Netherlands and DESY, Hamburg, Germany
| | - W Vulcan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - G Warren
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - S A Wood
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - C Xu
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - C Yan
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
| | - W-X Zhao
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - X Zheng
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - B Zihlmann
- Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA and University of Virginia, Charlottesville, Virginia 22901, USA
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Androic D, Armstrong DS, Asaturyan A, Averett T, Balewski J, Beaufait J, Beminiwattha RS, Benesch J, Benmokhtar F, Birchall J, Carlini RD, Cates GD, Cornejo JC, Covrig S, Dalton MM, Davis CA, Deconinck W, Diefenbach J, Dowd JF, Dunne JA, Dutta D, Duvall WS, Elaasar M, Falk WR, Finn JM, Forest T, Gaskell D, Gericke MTW, Grames J, Gray VM, Grimm K, Guo F, Hoskins JR, Johnston K, Jones D, Jones M, Jones R, Kargiantoulakis M, King PM, Korkmaz E, Kowalski S, Leacock J, Leckey J, Lee AR, Lee JH, Lee L, MacEwan S, Mack D, Magee JA, Mahurin R, Mammei J, Martin JW, McHugh MJ, Meekins D, Mei J, Michaels R, Micherdzinska A, Mkrtchyan A, Mkrtchyan H, Morgan N, Myers KE, Narayan A, Ndukum LZ, Nelyubin V, van Oers WTH, Opper AK, Page SA, Pan J, Paschke KD, Phillips SK, Pitt ML, Poelker M, Rajotte JF, Ramsay WD, Roche J, Sawatzky B, Seva T, Shabestari MH, Silwal R, Simicevic N, Smith GR, Solvignon P, Spayde DT, Subedi A, Subedi R, Suleiman R, Tadevosyan V, Tobias WA, Tvaskis V, Waidyawansa B, Wang P, Wells SP, Wood SA, Yang S, Young RD, Zhamkochyan S. First determination of the weak charge of the proton. Phys Rev Lett 2013; 111:141803. [PMID: 24152148 DOI: 10.1103/physrevlett.111.141803] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Indexed: 06/02/2023]
Abstract
The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 μA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.
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Affiliation(s)
- D Androic
- University of Zagreb, Zagreb HR-10002, Croatia
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21
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Androić D, Armstrong DS, Arvieux J, Bailey SL, Beck DH, Beise EJ, Benesch J, Benmokhtar F, Bimbot L, Birchall J, Bosted P, Breuer H, Capuano CL, Chao YC, Coppens A, Davis CA, Ellis C, Flores G, Franklin G, Furget C, Gaskell D, Gericke MTW, Grames J, Guillard G, Hansknecht J, Horn T, Jones MK, King PM, Korsch W, Kox S, Lee L, Liu J, Lung A, Mammei J, Martin JW, McKeown RD, Micherdzinska A, Mihovilovic M, Mkrtchyan H, Muether M, Page SA, Papavassiliou V, Pate SF, Phillips SK, Pillot P, Pitt ML, Poelker M, Quinn B, Ramsay WD, Real JS, Roche J, Roos P, Schaub J, Seva T, Simicevic N, Smith GR, Spayde DT, Stutzman M, Suleiman R, Tadevosyan V, van Oers WTH, Versteegen M, Voutier E, Vulcan W, Wells SP, Williamson SE, Wood SA. Measurement of the parity-violating asymmetry in inclusive electroproduction of π- near the Δ0 resonance. Phys Rev Lett 2012; 108:122002. [PMID: 22540573 DOI: 10.1103/physrevlett.108.122002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Indexed: 05/31/2023]
Abstract
The parity-violating (PV) asymmetry of inclusive π- production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasifree photoproduction off the neutron via the Δ0 resonance. In the context of heavy-baryon chiral perturbation theory, this asymmetry is related to a low-energy constant d(Δ)- that characterizes the parity-violating γNΔ coupling. Zhu et al. calculated d(Δ)- in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from A(γ)-=-5.2 to +5.2 ppm. The measurement performed in this work leads to A(γ)-=-0.36±1.06±0.37±0.03 ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to V(ud)/V(us). The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the N-Δ axial transition form factors using PV electron scattering.
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Affiliation(s)
- D Androić
- Department of Physics, University of Zagreb, Zagreb HR-41001, Croatia
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22
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Fomin N, Arrington J, Asaturyan R, Benmokhtar F, Boeglin W, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Daniel A, Day DB, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Gaskell D, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Mkrtchyan H, Navasardyan T, Niculescu G, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Seely J, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. New measurements of high-momentum nucleons and short-range structures in nuclei. Phys Rev Lett 2012; 108:092502. [PMID: 22463628 DOI: 10.1103/physrevlett.108.092502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Indexed: 05/31/2023]
Abstract
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate.
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Affiliation(s)
- N Fomin
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Krishnamurthy SV, Smith GR. Combined effects of malathion and nitrate on early growth, abnormalities, and mortality of wood frog (Rana sylvatica) tadpoles. Ecotoxicology 2011; 20:1361-1367. [PMID: 21533775 DOI: 10.1007/s10646-011-0692-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/18/2011] [Indexed: 05/30/2023]
Abstract
Use of pesticides and other agro-chemicals adversely influence amphibians either directly by killing them or by inducing sublethal, chronic effects. Many studies have investigated the effect of mixtures of pesticides or fertilizers. We studied the combined effects of nitrate and malathion ([(dimethoxy phosphino thioyl] butanediotae) on the early growth, expression of abnormalities, and mortality of Wood Frog (Rana sylvatica) tadpoles in a laboratory experiment. Tadpoles were treated with factorial combinations of 0, 8, and 16 mg NO(3)-N l(-1) and 0, 250, 500, and 1,000 μg malathion l(-1) for a period of 14 days. Feeding behaviour, total length, mean tadpole mass, frequencies of abnormalities, and survivorship in each treatment were recorded. Malathion showed a significant negative influence on all parameters and strongly influenced the frequencies of morphological anomalies. In contrast, nitrate alone did not produce any significant effects on behavior, total length, tadpole mass, or the frequency of abnormalities during the experiment. Malathion and nitrate had an interactive effect on tadpole length and mass, but did not affect any other parameters. Our results suggest that exposure to malathion, even at relatively low concentrations can have serious negative consequences for Wood Frog tadpoles. In addition, our results also indicate that there was little synergistic interaction between malathion and nitrate exposure under laboratory conditions.
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Affiliation(s)
- S V Krishnamurthy
- Department of Biology, Denison University, Granville, OH 43023, USA.
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Androić D, Armstrong DS, Arvieux J, Bailey SL, Beck DH, Beise EJ, Benesch J, Benmokhtar F, Bimbot L, Birchall J, Bosted P, Breuer H, Capuano CL, Chao YC, Coppens A, Davis CA, Ellis C, Flores G, Franklin G, Furget C, Gaskell D, Gericke MTW, Grames J, Guillard G, Hansknecht J, Horn T, Jones MK, King PM, Korsch W, Kox S, Lee L, Liu J, Lung A, Mammei J, Martin JW, McKeown RD, Micherdzinska A, Mihovilovic M, Mkrtchyan H, Muether M, Page SA, Papavassiliou V, Pate SF, Phillips SK, Pillot P, Pitt ML, Poelker M, Quinn B, Ramsay WD, Real JS, Roche J, Roos P, Schaub J, Seva T, Simicevic N, Smith GR, Spayde DT, Stutzman M, Suleiman R, Tadevosyan V, van Oers WTH, Versteegen M, Voutier E, Vulcan W, Wells SP, Williamson SE, Wood SA, Pasquini B, Vanderhaeghen M. Transverse beam spin asymmetries at backward angles in elastic electron-proton and quasielastic electron-deuteron scattering. Phys Rev Lett 2011; 107:022501. [PMID: 21797598 DOI: 10.1103/physrevlett.107.022501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Indexed: 05/31/2023]
Abstract
We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasielastic scattering on the deuteron, at backward angles (lab scattering angle of 108°) for Q² = 0.22 GeV²/c² and 0.63 GeV²/c² at beam energies of 362 and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single-photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (πN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasistatic deuterium approximation, and is also in agreement with theory.
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Affiliation(s)
- D Androić
- Department of Physics, University of Zagreb, Zagreb HR-41001, Croatia
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25
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Fomin N, Arrington J, Day DB, Gaskell D, Daniel A, Seely J, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Miyoshi T, Mkrtchyan H, Navasardyan T, Niculescu G, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. Scaling of the F2 structure function in nuclei and quark distributions at x>1. Phys Rev Lett 2010; 105:212502. [PMID: 21231294 DOI: 10.1103/physrevlett.105.212502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 05/30/2023]
Abstract
We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.
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Affiliation(s)
- N Fomin
- University of Virginia, Charlottesville, Virginia, USA
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Broadfoot AL, Atreya SK, Bertaux JL, Blamont JE, Dessler AJ, Donahue TM, Forrester WT, Hall DT, Herbert F, Holberg JB, Hunter DM, Krasnopolsky VA, Linick S, Lunine JI, McConnell JC, Moos HW, Sandel BR, Schneider NM, Shemansky DE, Smith GR, Strobel DF, Yelle RV. Ultraviolet spectrometer observations of neptune and triton. Science 2010; 246:1459-66. [PMID: 17756000 DOI: 10.1126/science.246.4936.1459] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Results from the occultation of the sun by Neptune imply a temperature of 750 +/- 150 kelvins in the upper levels of the atmosphere (composed mostly of atomic and molecular hydrogen) and define the distributions of methane, acetylene, and ethane at lower levels. The ultraviolet spectrum of the sunlit atmosphere of Neptune resembles the spectra of the Jupiter, Saturn, and Uranus atmospheres in that it is dominated by the emissions of H Lyman alpha (340 +/- 20 rayleighs) and molecular hydrogen. The extreme ultraviolet emissions in the range from 800 to 1100 angstroms at the four planets visited by Voyager scale approximately as the inverse square of their heliocentric distances. Weak auroral emissions have been tentatively identified on the night side of Neptune. Airglow and occultation observations of Triton's atmosphere show that it is composed mainly of molecular nitrogen, with a trace of methane near the surface. The temperature of Triton's upper atmosphere is 95 +/- 5 kelvins, and the surface pressure is roughly 14 microbars.
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27
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Broadfoot AL, Herbert F, Holberg JB, Hunten DM, Kumar S, Sandel BR, Shemansky DE, Smith GR, Yelle RV, Strobel DF, Moos HW, Donahue TM, Atreya SK, Bertaux JL, Blamont JE, McConnell JC, Dessler AJ, Linick S, Springer R. Ultraviolet spectrometer observations of uranus. Science 2010; 233:74-9. [PMID: 17812892 DOI: 10.1126/science.233.4759.74] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Data from solar and stellar occultations of Uranus indicate a temperature of about 750 kelvins in the upper levels of the atmosphere (composed mostly of atomic and molecular hydrogen) and define the distributions of methane and acetylene in the lower levels. The ultraviolet spectrum of the sunlit hemisphere is dominated by emissions from atomic and molecular hydrogen, which are kmown as electroglow emissions. The energy source for these emissions is unknown, but the spectrum implies excitation by low-energy electrons (modeled with a 3-electron-volt Maxwellian energy distribution). The major energy sink for the electrons is dissociation of molecular hydrogen, producing hydrogen atoms at a rate of 10(29) per second. Approximately half the atoms have energies higher than the escape energy. The high temperature of the atmosphere, the small size of Uranus, and the number density of hydrogen atoms in the thermosphere imply an extensive thermal hydrogen corona that reduces the orbital lifetime of ring particles and biases the size distribution toward larger particles. This corona is augmented by the nonthermal hydrogen atoms associated with the electroglow. An aurora near the magnetic pole in the dark hemisphere arises from excitation of molecular hydrogen at the level where its vertical column abundance is about 10(20) per square centimeter with input power comparable to that of the sunlit electroglow (approximately 2x10(11) watts). An initial estimate of the acetylene volume mixing ratio, as judged from measurements of the far ultraviolet albedo, is about 2 x 10(-7) at a vertical column abundance of molecular hydrogen of 10(23) per square centimeter (pressure, approximately 0.3 millibar). Carbon emissions from the Uranian atmosphere were also detected.
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Androić D, Armstrong DS, Arvieux J, Bailey SL, Beck DH, Beise EJ, Benesch J, Benmokhtar F, Bimbot L, Birchall J, Bosted P, Breuer H, Capuano CL, Chao YC, Coppens A, Davis CA, Ellis C, Flores G, Franklin G, Furget C, Gaskell D, Gericke MTW, Grames J, Guillard G, Hansknecht J, Horn T, Jones M, King PM, Korsch W, Kox S, Lee L, Liu J, Lung A, Mammei J, Martin JW, McKeown RD, Mihovilovic M, Micherdzinska A, Mkrtchyan H, Muether M, Page SA, Papavassiliou V, Pate SF, Phillips SK, Pillot P, Pitt ML, Poelker M, Quinn B, Ramsay WD, Real JS, Roche J, Roos P, Schaub J, Seva T, Simicevic N, Smith GR, Spayde DT, Stutzman M, Suleiman R, Tadevosyan V, van Oers WTH, Versteegen M, Voutier E, Vulcan W, Wells SP, Williamson SE, Wood SA. Strange quark contributions to parity-violating asymmetries in the backward angle G0 electron scattering experiment. Phys Rev Lett 2010; 104:012001. [PMID: 20366359 DOI: 10.1103/physrevlett.104.012001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Indexed: 05/29/2023]
Abstract
We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q2=0.22 and 0.63 GeV2. They are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of approximately < 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. We also present the first measurement of anapole moment effects in the axial-vector current at these four-momentum transfers.
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Affiliation(s)
- D Androić
- Department of Physics, University of Zagreb, Zagreb HR-41001, Croatia
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Seely J, Daniel A, Gaskell D, Arrington J, Fomin N, Solvignon P, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Clasie B, Connell S, Dalton MM, Day D, Dunne J, Dutta D, El Fassi L, Ent R, Fenker H, Filippone BW, Gao H, Hill C, Holt RJ, Horn T, Hungerford E, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lee C, Lung AF, Malace S, Meekins DG, Mertens T, Mkrtchyan H, Navasardyan T, Niculescu G, Niculescu I, Nomura H, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wesselmann FR, Wood SA, Wright J, Yuan L, Zheng X. New measurements of the European Muon Collaboration effect in very light nuclei. Phys Rev Lett 2009; 103:202301. [PMID: 20365978 DOI: 10.1103/physrevlett.103.202301] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 07/27/2009] [Indexed: 05/29/2023]
Abstract
New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from (2)H, (3)He, (4)He, (9)Be and (12)C for 0.3 < x < 0.9, Q(2) approximately 3-6 GeV(2). These data represent the first measurement of the EMC effect for (3)He at large x and a significant improvement for (4)He. The data do not support previous A-dependent or density-dependent fits to the EMC effect and suggest that the nuclear dependence of the quark distributions may depend on the local nuclear environment.
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Affiliation(s)
- J Seely
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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30
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Clasie B, Qian X, Arrington J, Asaturyan R, Benmokhtar F, Boeglin W, Bosted P, Bruell A, Christy ME, Chudakov E, Cosyn W, Dalton MM, Daniel A, Day D, Dutta D, El Fassi L, Ent R, Fenker HC, Ferrer J, Fomin N, Gao H, Garrow K, Gaskell D, Gray C, Horn T, Huber GM, Jones MK, Kalantarians N, Keppel CE, Kramer K, Larson A, Li Y, Liang Y, Lung AF, Malace S, Markowitz P, Matsumura A, Meekins DG, Mertens T, Miller GA, Miyoshi T, Mkrtchyan H, Monson R, Navasardyan T, Niculescu G, Niculescu I, Okayasu Y, Opper AK, Perdrisat C, Punjabi V, Rauf AW, Rodriquez VM, Rohe D, Ryckebusch J, Seely J, Segbefia E, Smith GR, Strikman M, Sumihama M, Tadevosyan V, Tang L, Tvaskis V, Villano A, Vulcan WF, Wesselmann FR, Wood SA, Yuan L, Zheng XC. Measurement of nuclear transparency for the A(e,e'pi+) reaction. Phys Rev Lett 2007; 99:242502. [PMID: 18233444 DOI: 10.1103/physrevlett.99.242502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2007] [Revised: 09/23/2007] [Indexed: 05/25/2023]
Abstract
We have measured the nuclear transparency of the A(e,e'pi+) process in 2H, 12C, 27Al, 63Cu, and 197Au targets. These measurements were performed at the Jefferson Laboratory over a four momentum transfer squared range Q2=1.1 to 4.7 (GeV/c)2. The nuclear transparency was extracted as the super-ratio of (sigmaA/sigmaH) from data to a model of pion-electroproduction from nuclei without pi-N final-state interactions. The Q2 and atomic number dependence of the nuclear transparency both show deviations from traditional nuclear physics expectations and are consistent with calculations that include the quantum chromodynamical phenomenon of color transparency.
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Affiliation(s)
- B Clasie
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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31
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Armstrong DS, Arvieux J, Asaturyan R, Averett T, Bailey SL, Batigne G, Beck DH, Beise EJ, Benesch J, Bimbot L, Birchall J, Biselli A, Bosted P, Boukobza E, Breuer H, Carlini R, Carr R, Chant N, Chao YC, Chattopadhyay S, Clark R, Covrig S, Cowley A, Dale D, Davis C, Falk W, Finn JM, Forest T, Franklin G, Furget C, Gaskell D, Grames J, Griffioen KA, Grimm K, Guillon B, Guler H, Hannelius L, Hasty R, Allen AH, Horn T, Johnston K, Jones M, Kammel P, Kazimi R, King PM, Kolarkar A, Korkmaz E, Korsch W, Kox S, Kuhn J, Lachniet J, Lee L, Lenoble J, Liatard E, Liu J, Loupias B, Lung A, Marchand D, Martin JW, McFarlane KW, McKee DW, McKeown RD, Merchez F, Mkrtchyan H, Moffit B, Morlet M, Nakagawa I, Nakahara K, Neveling R, Ong S, Page S, Papavassiliou V, Pate SF, Phillips SK, Pitt ML, Poelker M, Porcelli TA, Quéméner G, Quinn B, Ramsay WD, Rauf AW, Real JS, Roche J, Roos P, Rutledge GA, Secrest J, Simicevic N, Smith GR, Spayde DT, Stepanyan S, Stutzman M, Sulkosky V, Tadevosyan V, Tieulent R, Van de Wiele J, van Oers WTH, Voutier E, Vulcan W, Warren G, Wells SP, Williamson SE, Wood SA, Yan C, Yun J, Zeps V. Transverse beam spin asymmetries in forward-angle elastic electron-proton scattering. Phys Rev Lett 2007; 99:092301. [PMID: 17930999 DOI: 10.1103/physrevlett.99.092301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Indexed: 05/25/2023]
Abstract
We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely polarized 3 GeV electrons from unpolarized protons at Q2=0.15, 0.25 (GeV/c)2. The results are inconsistent with calculations solely using the elastic nucleon intermediate state and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A(n) provides a direct probe of the imaginary component of the 2gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.
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Affiliation(s)
- D S Armstrong
- Department of Physics, College of William and Mary, Williamsburg, Virginia 23187, USA
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Abstract
The mass-specific metabolic rate hypothesis of Gillooly and others predicts that DNA mutation and substitution rates are a function of body mass and temperature. We tested this hypothesis with sequence divergences estimated from mtDNA cytochrome b sequences of 54 taxa of cyprinid fish. Branch lengths estimated from a likelihood tree were compared with metabolic rates calculated from body mass and environmental temperatures experienced by those taxa. The problem of unknown age estimates of lineage splitting was avoided by comparing estimated amounts of metabolic activity along phyletic lines leading to pairs of modern taxa from their most recent common ancestor with sequence divergences along those same pairs of phyletic lines. There were significantly more pairs for which the phyletic line with greater genetic change also had the higher metabolic activity, when compared to the prediction of a hypothesis that body mass and temperature are not related to substitution rate.
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Affiliation(s)
- G F Estabrook
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan 48109, USA
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33
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Navasardyan T, Adams GS, Ahmidouch A, Angelescu T, Arrington J, Asaturyan R, Baker OK, Benmouna N, Bertoncini C, Blok HP, Boeglin WU, Bosted PE, Breuer H, Christy ME, Connell SH, Cui Y, Dalton MM, Danagoulian S, Day D, Dodario T, Dunne JA, Dutta D, El Khayari N, Ent R, Fenker HC, Frolov VV, Gan L, Gaskell D, Hafidi K, Hinton W, Holt RJ, Horn T, Huber GM, Hungerford E, Jiang X, Jones M, Joo K, Kalantarians N, Kelly JJ, Keppel CE, Kubarovski V, Li Y, Liang Y, Malace S, Markowitz P, McGrath E, McKee P, Meekins DG, Mkrtchyan H, Moziak B, Niculescu G, Niculescu I, Opper AK, Ostapenko T, Reimer P, Reinhold J, Roche J, Rock SE, Schulte E, Segbefia E, Smith C, Smith GR, Stoler P, Tadevosyan V, Tang L, Ungaro M, Uzzle A, Vidakovic S, Villano A, Vulcan WF, Wang M, Warren G, Wesselmann F, Wojtsekhowski B, Wood SA, Xu C, Yuan L, Zheng X, Zhu H. Onset of quark-hadron duality in pion electroproduction. Phys Rev Lett 2007; 98:022001. [PMID: 17358596 DOI: 10.1103/physrevlett.98.022001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Indexed: 05/14/2023]
Abstract
A large data set of charged-pion (pi+/-) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-->pion production mechanisms.
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Horn T, Aniol K, Arrington J, Barrett B, Beise EJ, Blok HP, Boeglin W, Brash EJ, Breuer H, Chang CC, Christy ME, Ent R, Gaskell D, Gibson E, Holt RJ, Huber GM, Jin S, Jones MK, Keppel CE, Kim W, King PM, Kovaltchouk V, Liu J, Lolos GJ, Mack DJ, Margaziotis DJ, Markowitz P, Matsumura A, Meekins D, Miyoshi T, Mkrtchyan H, Niculescu I, Okayasu Y, Pentchev L, Perdrisat C, Potterveld D, Punjabi V, Reimer P, Reinhold J, Roche J, Roos PG, Sarty A, Smith GR, Tadevosyan V, Tang LG, Tvaskis V, Vidakovic S, Volmer J, Vulcan W, Warren G, Wood SA, Xu C, Zheng X. Determination of the pion charge form factor at Q2=1.60 and 2.45 (GeV/c)2. Phys Rev Lett 2006; 97:192001. [PMID: 17155616 DOI: 10.1103/physrevlett.97.192001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Indexed: 05/12/2023]
Abstract
The 1H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F(pi)) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F(pi) is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative quantum chromodynamics prediction.
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Affiliation(s)
- T Horn
- Department of Physics, University of Maryland, College Park, MD 20742, USA
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35
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Abu Ahmad Y, Rassaby L, Royer M, Borg Z, Braithwaite KS, Mirkov TE, Irey MS, Perrier X, Smith GR, Rott P. Yellow leaf of sugarcane is caused by at least three different genotypes of sugarcane yellow leaf virus, one of which predominates on the Island of Réunion. Arch Virol 2006; 151:1355-71. [PMID: 16453082 DOI: 10.1007/s00705-005-0712-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Accepted: 12/14/2005] [Indexed: 10/25/2022]
Abstract
The genetic diversity of sugarcane yellow leaf virus (SCYLV) was analyzed with 43 virus isolates from Réunion Island and 17 isolates from world-wide locations. We attempted to amplify by reverse-transcription polymerase chain reaction (RT-PCR), clone, and sequence four different fragments covering 72% of the genome of these virus isolates. The number of amplified isolates and useful sequence information varied according to each fragment, whereas an amplicon was obtained with diagnostic primers for 59 out of 60 isolates (98%). Phylogenetic analyses of the sequences determined here and additional sequences of 11 other SCYLV isolates available from GenBank showed that SCYLV isolates were distributed in different phylogenetic groups or belonged to single genotypes. The majority of isolates from Réunion Island were grouped in phylogenetic clusters that did not contain any isolates from other origins. The complete six ORFs (5612 bp) of five SCYLV isolates (two from Réunion Island, one from Brazil, one from China, and one from Peru) were amplified, cloned, and sequenced. The existence of at least three distinct genotypes of SCYLV was shown by phylogenetic analysis of the sequences of these isolates and additional published sequences of three SCYLV isolates (GenBank accessions). The biological significance of these genotypes and of the origin of the distinct lineage of SCYLV in Réunion Island remains to be determined.
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Affiliation(s)
- Y Abu Ahmad
- UMR 385 AGRO.M-CIRAD-INRA Biologie et Génétique des Interactions Plante-Parasite, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Montpellier, France
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Smith GR, Temple KG, Vaala DA, Dingfelder HA. Effects of nitrate on the tadpoles of two Ranids (Rana catesbeiana and R. clamitans). Arch Environ Contam Toxicol 2005; 49:559-62. [PMID: 16001146 DOI: 10.1007/s00244-005-0004-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2005] [Accepted: 03/04/2005] [Indexed: 05/03/2023]
Abstract
Nitrate is a potential stressor of amphibian larvae. Previous research has shown variation in the effects of nitrate among species and even populations of amphibians. However, relatively few species and populations of amphibians have been examined for nitrate tolerance, especially from populations in the agricultural regions of the United States. Using a 15-day laboratory experiment, we investigated the effects of nitrate on the larvae of two species of anurans (Rana catesbeiana and R. clamitans) that are common throughout the agricultural Midwest. Survival of R. catesbeiana and R. clamitans tadpoles was negatively affected by higher concentrations of nitrate (20 mg L(-1)), with R. clamitans being more affected than R. catesbeiana. The final mass of R. catesbeiana tadpoles was affected by nitrate concentration, with tadpoles exposed to intermediate concentrations of nitrate (5 mg L(-1)) being the heaviest. The final mass of R. clamitans tadpoles was not affected by nitrate concentration. These experiments suggest that these two species differ in their responses to the toxic effects of nitrate and, along with previous results on Ranids, suggest there is a great deal of variation in nitrate tolerance in this family.
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Affiliation(s)
- G R Smith
- Department of Biology, Denison University, Granville, OH 43023, USA.
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37
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Armstrong DS, Arvieux J, Asaturyan R, Averett T, Bailey SL, Batigne G, Beck DH, Beise EJ, Benesch J, Bimbot L, Birchall J, Biselli A, Bosted P, Boukobza E, Breuer H, Carlini R, Carr R, Chant N, Chao YC, Chattopadhyay S, Clark R, Covrig S, Cowley A, Dale D, Davis C, Falk W, Finn JM, Forest T, Franklin G, Furget C, Gaskell D, Grames J, Griffioen KA, Grimm K, Guillon B, Guler H, Hannelius L, Hasty R, Hawthorne Allen A, Horn T, Johnston K, Jones M, Kammel P, Kazimi R, King PM, Kolarkar A, Korkmaz E, Korsch W, Kox S, Kuhn J, Lachniet J, Lee L, Lenoble J, Liatard E, Liu J, Loupias B, Lung A, MacLachlan GA, Marchand D, Martin JW, McFarlane KW, McKee DW, McKeown RD, Merchez F, Mkrtchyan H, Moffit B, Morlet M, Nakagawa I, Nakahara K, Nakos M, Neveling R, Niccolai S, Ong S, Page S, Papavassiliou V, Pate SF, Phillips SK, Pitt ML, Poelker M, Porcelli TA, Quéméner G, Quinn B, Ramsay WD, Rauf AW, Real JS, Roche J, Roos P, Rutledge GA, Secrest J, Simicevic N, Smith GR, Spayde DT, Stepanyan S, Stutzman M, Sulkosky V, Tadevosyan V, Tieulent R, van de Wiele J, van Oers W, Voutier E, Vulcan W, Warren G, Wells SP, Williamson SE, Wood SA, Yan C, Yun J, Zeps V. Strange-quark contributions to parity-violating asymmetries in the forward g0 electron-proton scattering experiment. Phys Rev Lett 2005; 95:092001. [PMID: 16197209 DOI: 10.1103/physrevlett.95.092001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2005] [Indexed: 05/04/2023]
Abstract
We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 < or =1.0 GeV2. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions to the currents of the proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate nonzero, Q2 dependent, strange-quark contributions and provide new information beyond that obtained in previous experiments.
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Affiliation(s)
- D S Armstrong
- Department of Physics, College of William and Mary, Williamsburg, VA 23187, USA
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Braithwaite KS, Geijskes RJ, Smith GR. A variable region of the sugarcane bacilliform virus (SCBV) genome can be used to generate promoters for transgene expression in sugarcane. Plant Cell Rep 2004; 23:319-26. [PMID: 15309498 DOI: 10.1007/s00299-004-0817-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2004] [Revised: 05/01/2004] [Accepted: 05/04/2004] [Indexed: 05/03/2023]
Abstract
Four promoters derived from sugarcane bacilliform virus (SCBV) were compared and characterised. Three were obtained by PCR amplification of purified virion DNA extracted from three sugarcane cultivars. The fourth promoter was obtained by subcloning from an almost genome-length clone of SCBV. All promoters were able to drive stable expression of beta-glucuronidase in sugarcane. The PCR-derived promoter sequences shared more DNA homology with banana streak virus than to the subcloned SCBV. The subcloned promoter was the strongest expressing and was able to drive reporter gene expression in vitro and in the leaves, meristems and roots of glasshouse-grown sugarcane. Expression levels were at least equal to or higher than those measured for the maize polyubiquitin promoter.
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Affiliation(s)
- K S Braithwaite
- David North Plant Research Centre, BSES Limited, P.O. Box 86, Indooroopilly, Queensland, 4068, Australia.
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39
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Abstract
Rheumatoid arthritis and juvenile arthritis represent the commonest diseases complicated by AA amyloidosis in developed countries. Up to 5% of patients with rheumatoid arthritis will develop AA amyloidosis, with renal failure being the commonest cause of mortality. To date, treatment of this condition has focused on suppressing the underlying inflammatory condition with drugs such as cyclophosphamide and chlorambucil, but both these drugs are associated with myelotoxicity, leukaemia and sterility. Tumour necrosis factor-alpha (TNF-alpha) is thought to be involved in amyloid deposition. The efficacy of anti-TNF-alpha therapy (etanercept) in the treatment of renal amyloidosis complicating rheumatoid arthritis is demonstrated here and the current scientific data on this subject are presented.
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Affiliation(s)
- G R Smith
- Department of Rheumatology, The Canberra Hospital, Canberra, Australian Capital Territory, Australia
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McIntyre CL, Hermann SM, Casu RE, Knight D, Drenth J, Tao Y, Brumbley SM, Godwin ID, Williams S, Smith GR, Manners JM. Homologues of the maize rust resistance gene Rp1-D are genetically associated with a major rust resistance QTL in sorghum. Theor Appl Genet 2004; 109:875-83. [PMID: 15156283 DOI: 10.1007/s00122-004-1702-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2003] [Accepted: 04/01/2004] [Indexed: 05/22/2023]
Abstract
As part of a comparative mapping study between sugarcane and sorghum, a sugarcane cDNA clone with homology to the maize Rp1-D rust resistance gene was mapped in sorghum. The cDNA probe hybridised to multiple loci, including one on sorghum linkage group (LG) E in a region where a major rust resistance QTL had been previously mapped. Partial sorghum Rp1-D homologues were isolated from genomic DNA of rust-resistant and -susceptible progeny selected from a sorghum mapping population. Sequencing of the Rp1-D homologues revealed five discrete sequence classes: three from resistant progeny and two from susceptible progeny. PCR primers specific to each sequence class were used to amplify products from the progeny and confirmed that the five sequence classes mapped to the same locus on LG E. Cluster analysis of these sorghum sequences and available sugarcane, maize and sorghum Rp1-D homologue sequences showed that the maize Rp1-D sequence and the partial sugarcane Rp1-D homologue were clustered with one of the sorghum resistant progeny sequence classes, while previously published sorghum Rp1-D homologue sequences clustered with the susceptible progeny sequence classes. Full-length sequence information was obtained for one member of a resistant progeny sequence class ( Rp1-SO) and compared with the maize Rp1-D sequence and a previously identified sorghum Rp1 homologue ( Rph1-2). There was considerable similarity between the two sorghum sequences and less similarity between the sorghum and maize sequences. These results suggest a conservation of function and gene sequence homology at the Rp1 loci of maize and sorghum and provide a basis for convenient PCR-based screening tools for putative rust resistance alleles in sorghum.
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Affiliation(s)
- C L McIntyre
- CSIRO Plant Industry, Queensland Bioscience Precinct, 306 Carmody Road, St. Lucia, Brisbane, QLD 4067, Australia.
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41
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Smith GR, Vaala DA, Dingfelder HA, Temple KG. Effects of nitrite on bullfrog (Rana catesbeiana) tadpoles from central Ohio, USA. Bull Environ Contam Toxicol 2004; 72:1012-1016. [PMID: 15266699 DOI: 10.1007/s00128-004-0344-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Affiliation(s)
- G R Smith
- Department of Biology, Denison University, Granville, OH 43023, USA
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42
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McQualter RB, Burns P, Smith GR, Dale JL, Harding RM. Molecular analysis of Fiji disease virus genome segments 5, 6, 8 and 10. Arch Virol 2004; 149:713-21. [PMID: 15045559 DOI: 10.1007/s00705-003-0243-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2003] [Accepted: 10/01/2003] [Indexed: 10/26/2022]
Abstract
The complete sequences of Fiji disease virus (FDV) genome segments 5 (S5), S6, S8 and S10 were obtained and comprised 3150 nt, 2831 nt, 1959 nt and 1819 nt, respectively. Each segment contained a single ORF which encoded putative proteins of 115 kDa, 97 kDa, 69 kDa and 63.0 kDa, respectively. The putative amino acid sequences encoded by S5 and S6 contained putative leucine zipper motifs while FDV S5 and S8 each contained an ATP-GTP-binding motif. At the amino acid level, FDV S5, S6, S8 and S10 showed most similarity to the corresponding segments of Rice black-streaked dwarf virus. Based on sequence similarities, it is predicted that FDV S8 encodes a minor core protein, while FDV S10 encodes an outer capsid protein. The evolutionary relationships of FDV to other reoviruses are discussed.
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Affiliation(s)
- R B McQualter
- Plant Biotechnology Program, Science Research Centre, Queensland University of Technology, Brisbane, Australia
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43
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Geijskes RJ, Braithwaite KS, Smith GR, Dale JL, Harding RM. Sugarcane bacilliform virus encapsidates genome concatamers and does not appear to integrate into the Saccharum officinarum genome. Arch Virol 2004; 149:791-8. [PMID: 15045565 DOI: 10.1007/s00705-003-0260-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2003] [Accepted: 10/16/2003] [Indexed: 10/26/2022]
Abstract
Sugarcane bacilliform virus (SCBV) DNA molecules larger than the complete genome length of 7.6 kbp were detected in infected plants and in virions. We have confirmed that these high molecular weight nucleic acids were open circular DNA and viral in origin. Due to their open circular conformation, accurate size determination of the DNA molecules was not possible using conventional electrophoresis. Using field inversion gel electrophoresis (FIGE), however, the DNA appeared to increase in genome size increments, with sizes ranging from 1 to 4 genomes (31 kbp) detected. The DNA was packaged into virions, which may explain the observation of purified virions with lengths corresponding to one, two or three times the modal length of 130 nm. The DNA products were possibly concatamers formed during replication as a result of a terminal overlap on the sense strand, and were shown to be overlapped individual genome-length molecules and not covalently-bonded continuous DNA strands. Southern analysis indicated that SCBV sequences are not integrated into the sugarcane genome and that the high molecular weight DNA observed in the sugarcane accessions analysed represents SCBV concatamers.
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Affiliation(s)
- R J Geijskes
- David North Plant Research Centre, Bureau of Sugar Experiment Stations, Indooroopilly, Queensland, Australia
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44
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Abstract
The genome of an Australian isolate of Sugarcane bacilliform virus (SCBV-IM) was cloned, sequenced and analysed. The genome consisted of 7687 nucleotides and contained three open reading frames which were similar in size and organisation to those of other badnaviruses. SCBV-IM was found to be most similar to the SCBV-Morocco isolate with amino acid sequence similarity of 91.4 %, 83.8 % and 85.3 % in the ORF I, II and III coding regions, respectively. Phylogenetic analysis of the SCBV-IM ORF III deduced amino acid sequence showed that SCBV isolates were more closely related to each other than to other badnaviruses. Amplification of SCBV sequences from three different sugarcane varieties revealed considerable variability in the viral populations, both within single infected plants as well as between infected plants, suggesting that the SCBV isolates sequenced to date may not be representative of the range of virus variability.
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Affiliation(s)
- R J Geijskes
- David North Plant Research Centre, Bureau of Sugar Experiment Stations, Indooroopilly, Queensland, Australia.
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45
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Abstract
Policy-makers have long suspected that greater barriers to care result in depressed rural residents being less likely to receive high-quality treatment. This study recruited 470 depressed community residents in a 1992 telephone survey, followed 95 percent of them through one year, and abstracted additional data on their health care utilization from insurance claims, medical and pharmacy records. Bivariate and multivariate models demonstrated that during the year following the baseline, there were no significant rural-urban differences in the rate (probability of any outpatient depression treatment), type (probability of receiving general medical depression care only), or quality (completion of guideline-concordant acute-stage care) of outpatient depression treatment. Annual expenditures for outpatient depression treatment were lower for rural subjects compared with their urban counterparts. Rural subjects had 3.05 times the odds of being admitted to a hospital for physical problems and 3.06 times the odds of being admitted to a hospital for mental health problems during the year following baseline compared with urban subjects. Cost-offset analyses demonstrate that every dollar invested in depression treatment was associated with a $2.61 decrease in the cost of treating physical problems in depressed rural residents. Limited insurance coverage and limited availability of services were the most significant barriers to specialty and general medical outpatient treatment for depression in both rural and urban residents. More than 80 percent of depressed residents in both rural and urban areas visited a primary care provider during the year following baseline. The potential cost offset of depression treatment in rural populations plus the improvement in productivity observed in both rural and urban populations indicate that it may be economically possible to improve quality of care for depression without bankrupting an already strained health care budget.
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Affiliation(s)
- K Rost
- University of Arkansas for Medical Sciences, Center for Rural Mental Healthcare Research, Little Rock 72204, USA
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46
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Abstract
Double-strand breaks and other lesions in DNA can stimulate homologous genetic recombination in two quite different ways: by promoting recombination near the break (roughly within a kb) or far from the break. Recent emphasis on the repair aspect of recombination has focused attention on DNA interactions and recombination near breaks. Here I review evidence for recombination far from DNA breaks in bacteria and fungi and discuss mechanisms by which this can occur. These mechanisms include entry of a traveling entity ("recombination machine") at a break, formation of long heteroduplex DNA, priming of DNA replication by a broken end, and induction of recombination potential in trans. Special emphasis is placed on contrasting views of how the RecBCD enzyme of Escherichia coli promotes recombination far (tens of kb) from a double-strand break. The occurrence of recombination far from DNA breaks and of correlated recombination events far apart suggests that "action at a distance" during recombination is a widespread feature among diverse organisms.
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Affiliation(s)
- G R Smith
- Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, Washington 98109, USA.
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Mizuno K, Hasemi T, Ubukata T, Yamada T, Lehmann E, Kohli J, Watanabe Y, Iino Y, Yamamoto M, Fox ME, Smith GR, Murofushi H, Shibata T, Ohta K. Counteracting regulation of chromatin remodeling at a fission yeast cAMP response element-related recombination hotspot by stress-activated protein kinase, cAMP-dependent kinase and meiosis regulators. Genetics 2001; 159:1467-78. [PMID: 11779789 PMCID: PMC1461918 DOI: 10.1093/genetics/159.4.1467] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
In fission yeast, an ATF/CREB-family transcription factor Atf1-Pcr1 plays important roles in the activation of early meiotic processes via the stress-activated protein kinase (SAPK) and the cAMP-dependent protein kinase (PKA) pathways. In addition, Atf1-Pcr1 binds to a cAMP responsive element (CRE)-like sequence at the site of the ade6-M26 mutation, which results in local enhancement of meiotic recombination and chromatin remodeling. Here we studied the roles of meiosis-inducing signal transduction pathways in M26 chromatin remodeling. Chromatin analysis revealed that persistent activation of PKA in meiosis inhibited M26 chromatin remodeling, suggesting that the PKA pathway represses M26 chromatin remodeling. The SAPK pathway activated M26 chromatin remodeling, since mutants lacking a component of this pathway, the Wis1 or Spc1/Sty1 kinases, had no M26 chromatin remodeling. M26 chromatin remodeling also required the meiosis regulators Mei2 and Mei3 but not the subsequently acting regulators Sme2 and Mei4, suggesting that induction of M26 chromatin remodeling needs meiosis-inducing signals before premeiotic DNA replication. Similar meiotic chromatin remodeling occurred meiotically around natural M26 heptamer sequences. These results demonstrate the coordinated action of genetic and physiological factors required to remodel chromatin in preparation for high levels of meiotic recombination and eukaryotic cellular differentiation.
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Affiliation(s)
- K Mizuno
- Genetic Dynamics Research Unit-Laboratory, RIKEN (The Institute of Physical and Chemical Research), Wako, Saitama 351-0198, Japan
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48
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Abstract
1. Introduction 4751.1 Ion channels 4751.1.1 Gramicidin 4761.1.2 Helix bundle channels 4771.1.3 K channels 4801.1.4 Porins 4831.1.5 Nicotinic acetylcholine receptor 4831.1.6 Physiological properties 4831.2 Simulations 4841.2.1 Atomistic versus mean-field simulations 4842. Atomistic simulations 4852.1 Modelling of ion-interaction parameters 4852.1.1 Interatomic distances and the problem of ionic radii 4862.1.2 Solvation energy 4872.1.3 Hydration shells and coordination numbers 4892.1.4 Parameters in common use and transferability 4912.1.5 Summary 4912.2 Water in pores versus bulk 4912.2.1 Simple pore models 4942.2.2 gA 4952.2.3 Alm 4962.2.4 LS36 (and LS24) 4962.2.5 Nicotinic receptor M2δ5 4972.2.6 Influenza A M2 4972.2.7 K channels 4972.2.8 nAChR 4982.2.9 Porins 4982.2.10 Relevance 4992.2.11 Problems with simulations 5012.3 Dynamics of ions in pores 5032.3.1 Simple pore models 5032.3.2 Helix bundles 5042.3.3 gA and KcsA 5052.4 Energetics of permeation and ion selectivity 5092.4.1 Potential and free energy profiles 5092.4.2 gA 5102.4.3 α-Helix bundles 5112.4.4 KcsA 5122.4.5 Ion selectivity 5142.4.6 Problems of estimating energetic profiles 5152.5 Conformational changes 5162.5.1 gA 5162.5.2 Alm and LS3 5162.5.3 KcsA 5172.6 Protonation states 5233. Coarse-grained simulations 5243.1 Introduction 5243.1.1 Predicting conductance magnitudes 5253.2 Electro-diffusion: the Nernst–Planck approach 5263.2.1 Calculating the potential profile from Poisson and PB theory 5283.2.2 Calculating the potential profile from BD simulations 5303.2.3 Combining Nernst–Planck and Poisson: PNP 5303.3 Beyond PNP 5323.4 BD simulations 5323.4.1 Basic theory in ion channels 5323.4.2 Incorporating the environment 5333.5 Applications 5353.5.1 Model systems 5353.5.1.1 Solving the Poisson and PB equation for channel-like geometries 5353.5.1.2 Comparing PB, PNP and BD 5363.5.2 Applications to known structures 5373.5.2.1 gA 5373.5.2.2 Porin 5393.5.2.3 LS3 5403.5.2.4 Alm 5423.5.2.5 nAChR 5423.5.2.6 KcsA 5433.6 pKa calculations 5433.7 Selectivity 5443.7.1 Anion/cation selectivity 5453.7.2 Monovalent/divalent ion selectivity 5454. Problems 5464.1 Atomistic simulations 5464.1.1 Problems 5464.1.2 Parameters 5484.2 BD 5494.3 Mean-field simulations 5495. Conclusions 5505.1 Progress 5505.2 The future 5506. Acknowledgements 5517. References 551Ion channels are proteins that form ‘holes’ in membranes through which selected ions move
passively down their electrochemical gradients. The ions move quickly, at (nearly) diffusion
limited rates (ca. 107 ions s−1 per channel). Ion channels are central to many properties of cell
membranes. Traditionally they have been the concern of neuroscientists, as they control the
electrical properties of the membranes of excitable cells (neurones, muscle; Hille, 1992).
However, it is evident that ion channels are present in many types of cell, not all of which
are electrically excitable, from diverse organisms, including plants, bacteria and viruses
(where they are involved in functions such as cell homeostasis) in addition to animals. Thus
ion channels are of general cell biological importance. They are also of biomedical interest,
as several dizeases (‘channelopathies’) have been described which are caused by changes in
properties of a specific ion channel (Ashcroft, 2000). Moreover, passive diffusion channels for
substances other than ions are common (porins, aquaporins), as are active membrane
transport processes coupled to ion gradients or ATP hydrolysis. An understanding of ion
channels may also provide a gateway to understanding these processes.
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Affiliation(s)
- D P Tieleman
- Laboratory of Molecular Biophysics, Department of Biochemistry, Rex Richards Building, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
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49
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Smith GR. Effects of acute exposure to a commercial formulation of glyphosate on the tadpoles of two species of anurans. Bull Environ Contam Toxicol 2001; 67:483-8. [PMID: 11779061 DOI: 10.1007/s001280149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Affiliation(s)
- G R Smith
- Department of Biology, Denison University, Granville, OH 43023, USA
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50
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Ranatunga KM, Law RJ, Smith GR, Sansom MS. Electrostatics studies and molecular dynamics simulations of a homology model of the Shaker K+ channel pore. Eur Biophys J 2001; 30:295-303. [PMID: 11548132 DOI: 10.1007/s002490100134] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A homology model of the pore domain of the Shaker K+ channel has been constructed using a bacterial K+ channel, KcsA, as a template structure. The model is in agreement with mutagenesis and sequence variability data. A number of structural features are conserved between the two channels, including a ring of tryptophan sidechains on the outer surface of the pore domain at the extracellular end of the helix bundle, and rings of acidic sidechains close to the extracellular mouth of the channel. One of these rings, that formed by four Asp447 sidechains at the mouth of the Shaker pore, is shown by pK(A) calculations to be incompletely ionized at neutral pH. The potential energy profile for a K+ ion moved along the central axis of the Shaker pore domain model selectivity filter reveals a shallow well, the depth of which is modulated by the ionization state of the Asp447 ring. This is more consistent with the high cation flux exhibited by the channel in its conductance value of 19 pS.
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Affiliation(s)
- K M Ranatunga
- Department of Biochemistry, University of Oxford, UK
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