1
|
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.
Collapse
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
| |
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Androic D, Armstrong D, Asaturyan A, Averett T, Balewski J, Bartlett K, Beaufait J, Beminiwattha R, Benesch J, Benmokhtar F, Birchall J, Carlini R, Cates G, Cornejo J, Covrig S, Dalton M, Davis C, Deconinck W, Diefenbach J, Dowd J, Dunne J, Dutta D, Duvall W, Elaasar M, Falk W, Finn J, Forest T, Gal C, Gaskell D, Gericke M, Grames J, Gray V, Grimm K, Guo F, Hoskins J, Johnston K, Jones D, Jones M, Jones R, Kargiantoulakis M, King P, Korkmaz E, Kowalski S, Leacock J, Leckey J, Lee A, Lee J, Lee L, MacEwan S, Mack D, Magee J, Mahurin R, Mammei J, Martin J, McHugh M, Meekins D, Mei J, Michaels R, Micherdzinska A, Mkrtchyan A, Mkrtchyan H, Morgan N, Myers K, Narayan A, Ndukum L, Nelyubin V, Nuhait H, Nuruzzaman, van Oers W, Opper A, Page S, Pan J, Paschke K, Phillips S, Pitt M, Poelker M, Rajotte J, Ramsay W, Roche J, Sawatzky B, Seva T, Shabestari M, Silwal R, Simicevic N, Smith G, Solvignon P, Spayde D, Subedi A, Subedi R, Suleiman R, Tadevosyan V, Tobias W, Tvaskis V, Waidyawansa B, Wang P, Wells S, Wood S, Yang S, Young R, Zang P, Zhamkochyan S. Qweak: First Direct Measurement of the Proton’s Weak Charge. EPJ Web Conf 2017. [DOI: 10.1051/epjconf/201713708005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Androic D, Armstrong D, Asaturyan A, Averett T, Balewski J, Beaufait J, Beminiwattha R, Benesch J, Benmokhtar F, Birchall J, Carlini R, Cates G, Cornejo J, Covrig S, Dalton M, Davis C, Deconinck W, Diefenbach J, Dowd J, Dunne J, Dutta D, Duvall W, Elaasar M, Falk W, Finn J, Forest T, Gaskell D, Gericke M, Grames J, Gray V, Grimm K, Guo F, Hoskins J, Johnston K, Jones D, Jones M, Jones R, Kargiantoulakis M, King P, Korkmaz E, Kowalski S, Leacock J, Leckey J, Lee A, Lee J, Lee L, MacEwan S, Mack D, Magee J, Mahurin R, Mammei J, Martin J, McHugh M, Meekins D, Mei J, Michaels R, Micherdzinska A, Mkrtchyan A, Mkrtchyan H, Morgan N, Myers K, Narayan A, Ndukum L, Nelyubin V, Nuruzzaman, van Oers W, Opper A, Page S, Pan J, Paschke K, Phillips S, Pitt M, Poelker M, Rajotte J, Ramsay W, Roche J, Sawatzky B, Seva T, Shabestari M, Silwal R, Simicevic N, Smith G, Solvignon P, Spayde D, Subedi A, Subedi R, Suleiman R, Tadevosyan V, Tobias W, Tvaskis V, Waidyawansa B, Wang P, Wells S, Wood S, Yang S, Young R, Zhamkochyan S. Early Results from the QweakExperiment. EPJ Web of Conferences 2014. [DOI: 10.1051/epjconf/20146605002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
8
|
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.
Collapse
Affiliation(s)
- D Androic
- University of Zagreb, Zagreb HR-10002, Croatia
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Nakamura SN, Matsumura A, Okayasu Y, Seva T, Rodriguez VM, Baturin P, Yuan L, Acha A, Ahmidouch A, Androic D, Asaturyan A, Asaturyan R, Baker OK, Benmokhtar F, Bosted P, Carlini R, Chen C, Christy M, Cole L, Danagoulian S, Daniel A, Dharmawardane V, Egiyan K, Elaasar M, Ent R, Fenker H, Fujii Y, Furic M, Gan L, Gaskell D, Gasparian A, Gibson EF, Gogami T, Gueye P, Han Y, Hashimoto O, Hiyama E, Honda D, Horn T, Hu B, Hungerford EV, Jayalath C, Jones M, Johnston K, Kalantarians N, Kanda H, Kaneta M, Kato F, Kato S, Kawama D, Keppel C, Lan KJ, Luo W, Mack D, Maeda K, Malace S, Margaryan A, Marikyan G, Markowitz P, Maruta T, Maruyama N, Miyoshi T, Mkrtchyan A, Mkrtchyan H, Nagao S, Navasardyan T, Niculescu G, Niculescu MI, Nomura H, Nonaka K, Ohtani A, Oyamada M, Perez N, Petkovic T, Randeniya S, Reinhold J, Roche J, Sato Y, Segbefia EK, Simicevic N, Smith G, Song Y, Sumihama M, Tadevosyan V, Takahashi T, Tang L, Tsukada K, Tvaskis V, Vulcan W, Wells S, Wood SA, Yan C, Zhamkochyan S. Observation of the (Λ)(7)He hypernucleus by the (e, e'K+) reaction. Phys Rev Lett 2013; 110:012502. [PMID: 23383783 DOI: 10.1103/physrevlett.110.012502] [Citation(s) in RCA: 5] [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: 07/02/2012] [Indexed: 06/01/2023]
Abstract
An experiment with a newly developed high-resolution kaon spectrometer and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab. The ground state of a neutron-rich hypernucleus, (Λ)(7)He, was observed for the first time with the (e, e'K+) reaction with an energy resolution of ~0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The (Λ)(7)He binding energy supplies the last missing information of the A = 7, T = 1 hypernuclear isotriplet, providing a new input for the charge symmetry breaking effect of the ΛN potential.
Collapse
Affiliation(s)
- S N Nakamura
- Graduate School of Science, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Baillie N, Tkachenko S, Zhang J, Bosted P, Bültmann S, Christy ME, Fenker H, Griffioen KA, Keppel CE, Kuhn SE, Melnitchouk W, Tvaskis V, Adhikari KP, Adikaram D, Aghasyan M, Amaryan MJ, Anghinolfi M, Arrington J, Avakian H, Baghdasaryan H, Battaglieri M, Biselli AS, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Carman DS, Celentano A, Chandavar S, Charles G, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Daniel A, Dashyan N, De Vita R, De Sanctis E, Deur A, Dey B, Djalali C, Dodge G, Domingo J, Doughty D, Dupre R, Dutta D, Ent R, Egiyan H, El Alaoui A, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Fegan S, Fradi A, Gabrielyan MY, Gevorgyan N, Gilfoyle GP, Giovanetti KL, Girod FX, Gohn W, Golovatch E, Gothe RW, Graham L, Guegan B, Guidal M, Guler N, Guo L, Hafidi K, Heddle D, Hicks K, Holtrop M, Hungerford E, Hyde CE, Ilieva Y, Ireland DG, Ispiryan M, Isupov EL, Jawalkar SS, Jo HS, Kalantarians N, Khandaker M, Khetarpal P, Kim A, Kim W, King PM, Klein A, Klein FJ, Klimenko A, Kubarovsky V, Kuleshov SV, Kvaltine ND, Livingston K, Lu HY, MacGregor IJD, Mao Y, Markov N, McKinnon B, Mineeva T, Morrison B, Moutarde H, Munevar E, Nadel-Turonski P, Ni A, Niccolai S, Niculescu I, Niculescu G, Osipenko M, Ostrovidov AI, Pappalardo L, Park K, Park S, Pasyuk E, Anefalos Pereira S, Pisano S, Pozdniakov S, Price JW, Procureur S, Prok Y, Protopopescu D, Raue BA, Ricco G, Rimal D, Ripani M, Rosner G, Rossi P, Sabatié F, Saini MS, Salgado C, Schott D, Schumacher RA, Seder E, Sharabian YG, Sober DI, Sokhan D, Stepanyan S, Stepanyan SS, Stoler P, Strauch S, Taiuti M, Tang W, Ungaro M, Vineyard MF, Voutier E, Watts DP, Weinstein LB, Weygand DP, Wood MH, Zana L, Zhao B. Measurement of the neutron F2 structure function via spectator tagging with CLAS. Phys Rev Lett 2012; 108:142001. [PMID: 22540786 DOI: 10.1103/physrevlett.108.142001] [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: 10/12/2011] [Indexed: 05/31/2023]
Abstract
We report on the first measurement of the F(2) structure function of the neutron from the semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ≲100 MeV/c and their angles to ≳100° relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F(2)(n) data collected cover the nucleon-resonance and deep-inelastic regions over a wide range of Bjorken x for 0.65<Q(2)<4.52 GeV(2), with uncertainties from nuclear corrections estimated to be less than a few percent. These measurements provide the first determination of the neutron to proton structure function ratio F(2)(n)/F(2)(p) at 0.2≲x≲0.8 with little uncertainty due to nuclear effects.
Collapse
Affiliation(s)
- N Baillie
- College of William and Mary, Williamsburg, Virginia 23187, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
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.
Collapse
Affiliation(s)
- N Fomin
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Malace SP, Paolone M, Strauch S, Albayrak I, Arrington J, Berman BL, Brash EJ, Briscoe B, Camsonne A, Chen JP, Christy ME, Chudakov E, Cisbani E, Craver B, Cusanno F, Ent R, Garibaldi F, Gilman R, Glamazdin O, Glister J, Higinbotham DW, Hyde-Wright CE, Ilieva Y, de Jager CW, Jiang X, Jones MK, Keppel CE, Khrosinkova E, Kuchina E, Kumbartzki G, Lee B, Lindgren R, Margaziotis DJ, Meekins D, Michaels R, Park K, Pentchev L, Perdrisat CF, Piasetzky E, Punjabi VA, Puckett AJR, Qian X, Qiang Y, Ransome RD, Saha A, Sarty AJ, Schulte E, Solvignon P, Subedi RR, Tang L, Tedeschi D, Tvaskis V, Udias JM, Ulmer PE, Vignote JR, Wesselmann FR, Wojtsekhowski B, Zhan X. Precise extraction of the induced polarization in the 4He(e,e'p)3H reaction. Phys Rev Lett 2011; 106:052501. [PMID: 21405386 DOI: 10.1103/physrevlett.106.052501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Indexed: 05/30/2023]
Abstract
We measured with unprecedented precision the induced polarization P(y) in (4)He(e,e'p)(3)H at Q(2)=0.8 and 1.3 (GeV/c)(2). The induced polarization is indicative of reaction-mechanism effects beyond the impulse approximation. Our results are in agreement with a relativistic distorted-wave impulse approximation calculation but are overestimated by a calculation with strong charge-exchange effects. Our data are used to constrain the strength of the spin-independent charge-exchange term in the latter calculation.
Collapse
Affiliation(s)
- S P Malace
- University of South Carolina, Columbia, South Carolina 29208, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
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.
Collapse
Affiliation(s)
- N Fomin
- University of Virginia, Charlottesville, Virginia, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Paolone M, Malace SP, Strauch S, Albayrak I, Arrington J, Berman BL, Brash EJ, Briscoe B, Camsonne A, Chen JP, Christy ME, Chudakov E, Cisbani E, Craver B, Cusanno F, Ent R, Garibaldi F, Gilman R, Glamazdin O, Glister J, Higinbotham DW, Hyde-Wright CE, Ilieva Y, de Jager CW, Jiang X, Jones MK, Keppel CE, Khrosinkova E, Kuchina E, Kumbartzki G, Lee B, Lindgren R, Margaziotis DJ, Meekins D, Michaels R, Park K, Pentchev L, Perdrisat CF, Piasetzky E, Punjabi VA, Puckett AJR, Qian X, Qiang Y, Ransome RD, Saha A, Sarty AJ, Schulte E, Solvignon P, Subedi RR, Tang L, Tedeschi D, Tvaskis V, Udias JM, Ulmer PE, Vignote JR, Wesselmann FR, Wojtsekhowski B, Zhan X. Polarization transfer in the 4He(e,e'p)3H reaction at Q2=0.8 and 1.3 (GeV/c)2. Phys Rev Lett 2010; 105:072001. [PMID: 20868031 DOI: 10.1103/physrevlett.105.072001] [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: 02/19/2010] [Indexed: 05/29/2023]
Abstract
Proton recoil polarization was measured in the quasielastic 4He(e,e'p)3H reaction at Q{2}=0.8 and 1.3 (GeV/c){2} with unprecedented precision. The polarization-transfer coefficients are found to differ from those of the 1H(e,e'p) reaction, contradicting a relativistic distorted-wave approximation and favoring either the inclusion of medium-modified proton form factors predicted by the quark-meson coupling model or a spin-dependent charge-exchange final-state interaction. For the first time, the polarization-transfer ratio is studied as a function of the virtuality of the proton.
Collapse
Affiliation(s)
- M Paolone
- University of South Carolina, Columbia, South Carolina 29208, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
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.
Collapse
Affiliation(s)
- J Seely
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
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.
Collapse
Affiliation(s)
- B Clasie
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Tvaskis V, Christy ME, Arrington J, Asaturyan R, Baker OK, Blok HP, Bosted P, Boswell M, Bruell A, Cochran A, Cole L, Crowder J, Dunne J, Ent R, Fenker HC, Filippone BW, Garrow K, Gasparian A, Gomez J, Jackson HE, Keppel CE, Kinney E, Lapikás L, Liang Y, Lorenzon W, Lung A, Mack DJ, Martin JW, McIlhany K, Meekins D, Milner RG, Mitchell JH, Mkrtchyan H, Moreland B, Nazaryan V, Niculescu I, Opper A, Piercey RB, Potterveld DH, Rose B, Sato Y, Seo W, Smith G, Spurlock K, van der Steenhoven G, Stepanyan S, Tadevosian V, Uzzle A, Vulcan WF, Wood SA, Zihlmann B, Ziskin V. Longitudinal-transverse separations of deep-inelastic structure functions at low Q2 for hydrogen and deuterium. Phys Rev Lett 2007; 98:142301. [PMID: 17501267 DOI: 10.1103/physrevlett.98.142301] [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: 11/10/2006] [Indexed: 05/15/2023]
Abstract
We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06<Q2<2.8 GeV2. Even at the lowest values of Q2, R remains nearly constant and does not disappear with decreasing Q2, as might be expected. We find a nearly identical behavior for hydrogen and deuterium.
Collapse
Affiliation(s)
- V Tvaskis
- Vrije Universiteit, 1081 HV Amsterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
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.
Collapse
Affiliation(s)
- T Horn
- Department of Physics, University of Maryland, College Park, MD 20742, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|