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Dieterle M, Witthauer L, Fix A, Abt S, Achenbach P, Adlarson P, Afzal F, Aguar Bartolome P, Ahmed Z, Annand JRM, Arends HJ, Bashkanov M, Beck R, Biroth M, Borisov N, Braghieri A, Briscoe WJ, Cividini F, Collicott C, Costanza S, Denig A, Dolzhikov AS, Downie EJ, Drexler P, Gardner S, Ghosal D, Glazier DI, Gorodnov I, Gradl W, Günther M, Gurevich D, Heijkenskjöld L, Hornidge D, Huber GM, Käser A, Kashevarov VL, Kay S, Keshelashvili I, Kondratiev R, Korolija M, Krusche B, Lazarev A, Lisin V, Livingston K, Lutterer S, MacGregor IJD, Manley DM, Martel PP, Metag V, Meyer W, Middleton DG, Miskimen R, Mornacchi E, Mullen C, Mushkarenkov A, Neganov A, Neiser A, Oberle M, Ostrick M, Otte PB, Paudyal D, Pedroni P, Polonski A, Powell A, Prakhov SN, Reicherz G, Ron G, Rostomyan T, Sarty A, Sfienti C, Sokhoyan V, Spieker K, Steffen O, Strakovsky II, Strub T, Supek I, Thiel A, Thiel M, Thomas A, Unverzagt M, Usov YA, Wagner S, Walford NK, Watts DP, Werthmüller D, Wettig J, Wolfes M, Zana LA. Helicity-Dependent Cross Sections for the Photoproduction of π^{0} Pairs from Nucleons. Phys Rev Lett 2020; 125:062001. [PMID: 32845675 DOI: 10.1103/physrevlett.125.062001] [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: 01/10/2020] [Revised: 05/17/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
The double-polarization observable E and helicity-dependent cross sections σ_{1/2}, σ_{3/2} have been measured for the photoproduction of π^{0} pairs off quasifree protons and neutrons at the Mainz MAMI accelerator with the Crystal Ball/TAPS setup. A circularly polarized photon beam was produced by bremsstrahlung from longitudinally polarized electrons and impinged on a longitudinally polarized deuterated butanol target. The reaction products were detected with an almost 4π covering calorimeter. The results reveal for the first time the helicity- and isospin-dependent structure of the γN→Nπ^{0}π^{0} reaction. They are compared to predictions from reaction models in view of nucleon resonance contributions and also to a refit of one model that predicted results for the proton and for the neutron target. The comparison of the prediction and the refit demonstrates the large impact of the new data.
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Affiliation(s)
- M Dieterle
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - L Witthauer
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - A Fix
- Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634034 Tomsk, Russia
| | - S Abt
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - P Achenbach
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - P Adlarson
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - F Afzal
- Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, D-53115 Bonn, Germany
| | - P Aguar Bartolome
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan S4S-0A2 Canada
| | - J R M Annand
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - H J Arends
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - M Bashkanov
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - R Beck
- Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, D-53115 Bonn, Germany
| | - M Biroth
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - N Borisov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - A Braghieri
- INFN Sezione di Pavia, I-27100 Pavia, Pavia, Italy
| | - W J Briscoe
- Center for Nuclear Studies, The George Washington University, Washington, DC 20052, USA
| | - F Cividini
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - C Collicott
- Department of Astronomy and Physics, Saint Mary's University, E4L1E6 Halifax, Canada
| | - S Costanza
- INFN Sezione di Pavia, I-27100 Pavia, Pavia, Italy
| | - A Denig
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - A S Dolzhikov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - E J Downie
- Center for Nuclear Studies, The George Washington University, Washington, DC 20052, USA
| | - P Drexler
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
- II. Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - S Gardner
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - D Ghosal
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - D I Glazier
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - I Gorodnov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - W Gradl
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - M Günther
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - D Gurevich
- Institute for Nuclear Research, RU-125047 Moscow, Russia
| | - L Heijkenskjöld
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - D Hornidge
- Mount Allison University, Sackville, New Brunswick E4L1E6, Canada
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S-0A2 Canada
| | - A Käser
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - V L Kashevarov
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - S Kay
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - I Keshelashvili
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - R Kondratiev
- Institute for Nuclear Research, RU-125047 Moscow, Russia
| | - M Korolija
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - B Krusche
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - A Lazarev
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - V Lisin
- Institute for Nuclear Research, RU-125047 Moscow, Russia
| | - K Livingston
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - S Lutterer
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - I J D MacGregor
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - D M Manley
- Kent State University, Kent, Ohio 44242, USA
| | - P P Martel
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
- Mount Allison University, Sackville, New Brunswick E4L3B5, Canada
| | - V Metag
- II. Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - W Meyer
- Institut für Experimentalphysik, Ruhr Universität, 44780 Bochum, Germany
| | - D G Middleton
- Mount Allison University, Sackville, New Brunswick E4L3B5, Canada
| | - R Miskimen
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - E Mornacchi
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - C Mullen
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - A Mushkarenkov
- INFN Sezione di Pavia, I-27100 Pavia, Pavia, Italy
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - A Neganov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - A Neiser
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - M Oberle
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - M Ostrick
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - P B Otte
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - D Paudyal
- University of Regina, Regina, Saskatchewan S4S-0A2 Canada
| | - P Pedroni
- INFN Sezione di Pavia, I-27100 Pavia, Pavia, Italy
| | - A Polonski
- Institute for Nuclear Research, RU-125047 Moscow, Russia
| | - A Powell
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - S N Prakhov
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - G Reicherz
- Institut für Experimentalphysik, Ruhr Universität, 44780 Bochum, Germany
| | - G Ron
- Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - T Rostomyan
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - A Sarty
- Department of Astronomy and Physics, Saint Mary's University, E4L1E6 Halifax, Canada
| | - C Sfienti
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - V Sokhoyan
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - K Spieker
- Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, D-53115 Bonn, Germany
| | - O Steffen
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - I I Strakovsky
- Center for Nuclear Studies, The George Washington University, Washington, DC 20052, USA
| | - T Strub
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - I Supek
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - A Thiel
- Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, D-53115 Bonn, Germany
| | - M Thiel
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - A Thomas
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - M Unverzagt
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - Yu A Usov
- Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - S Wagner
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - N K Walford
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
| | - D P Watts
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Werthmüller
- Department of Physics, University of Basel, CH-4056 Basel, Switzerland
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - J Wettig
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - M Wolfes
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - L A Zana
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
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Beričič J, Correa L, Benali M, Achenbach P, Ayerbe Gayoso C, Bernauer JC, Blomberg A, Böhm R, Bosnar D, Debenjak L, Denig A, Distler MO, Downie EJ, Esser A, Fonvieille H, Friščić I, Kegel S, Kohl Y, Makek M, Merkel H, Middleton DG, Mihovilovič M, Müller U, Nungesser L, Paolone M, Pochodzalla J, Sánchez Majos S, Schlimme BS, Schoth M, Schulz F, Sfienti C, Širca S, Sparveris N, Štajner S, Thiel M, Tyukin A, Weber A, Weinriefer M. New Insight in the Q^{2} Dependence of Proton Generalized Polarizabilities. Phys Rev Lett 2019; 123:192302. [PMID: 31765208 DOI: 10.1103/physrevlett.123.192302] [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: 07/24/2019] [Revised: 10/04/2019] [Indexed: 06/10/2023]
Abstract
Virtual Compton scattering on the proton has been investigated at three yet unexplored values of the four-momentum transfer Q^{2}: 0.10, 0.20, and 0.45 GeV^{2}, at the Mainz Microtron. Fits performed using either the low-energy theorem or dispersion relations allowed the extraction of the structure functions P_{LL}-P_{TT}/ε and P_{LT}, as well as the electric and magnetic generalized polarizabilities α_{E1}(Q^{2}) and β_{M1}(Q^{2}). These new results show a smooth and rapid falloff of α_{E1}(Q^{2}), in contrast to previous measurements at Q^{2}=0.33 GeV^{2}, and provide for the first time a precise mapping of β_{M1}(Q^{2}) in the low-Q^{2} region.
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Affiliation(s)
- J Beričič
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - L Correa
- Université Clermont Auvergne, CNRS/IN2P3, LPC, F-63000 Clermont-Ferrand, France
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Benali
- Université Clermont Auvergne, CNRS/IN2P3, LPC, F-63000 Clermont-Ferrand, France
| | - P Achenbach
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - C Ayerbe Gayoso
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - J C Bernauer
- Department of Physics and Astronomy, Stony Brook University, SUNY, Stony Brook, New York 11794-3800, USA
- RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - A Blomberg
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - R Böhm
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - D Bosnar
- Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia
| | - L Debenjak
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - A Denig
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M O Distler
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - E J Downie
- Institute for Nuclear Studies, Department of Physics, The George Washington University, Washington, DC 20052, USA
| | - A Esser
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - H Fonvieille
- Université Clermont Auvergne, CNRS/IN2P3, LPC, F-63000 Clermont-Ferrand, France
| | - I Friščić
- Laboratory for Nuclear Science, Massachussetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - S Kegel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - Y Kohl
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Makek
- Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia
| | - H Merkel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - D G Middleton
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Mihovilovič
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - U Müller
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - L Nungesser
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Paolone
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - J Pochodzalla
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - S Sánchez Majos
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - B S Schlimme
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Schoth
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - F Schulz
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - C Sfienti
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - S Širca
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
- Faculty of Mathematics and Physics, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - N Sparveris
- Temple University, Philadelphia, Pennsylvania 19122, USA
| | - S Štajner
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - M Thiel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - A Tyukin
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - A Weber
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Weinriefer
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
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3
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Kashevarov VL, Ott P, Prakhov S, Adlarson P, Afzal F, Ahmed Z, Akondi CS, Annand JRM, Arends HJ, Beck R, Braghieri A, Briscoe WJ, Cividini F, Codling R, Collicott C, Costanza S, Denig A, Downie EJ, Dieterle M, Ferretti Bondy MI, Fil'kov LV, Fix A, Gardner S, Garni S, Glazier DI, Glowa D, Gradl W, Gurevich G, Hamilton DJ, Hornidge D, Howdle D, Huber GM, Käser A, Kay S, Keshelashvili I, Kondratiev R, Korolija M, Krusche B, Linturi J, Lisin V, Livingston K, MacGregor IJD, MacRae R, Mancell J, Manley DM, Martel PP, McGeorge JC, McNicol E, Middleton DG, Miskimen R, Mornacchi E, Mullen C, Mushkarenkov A, Neiser A, Oberle M, Ostrick M, Otte PB, Oussena B, Paudyal D, Pedroni P, Polyanski VV, Rajabi A, Reicherz G, Robinson J, Rosner G, Rostomyan T, Sarty A, Schott DM, Schumann S, Sfienti C, Sokhoyan V, Spieker K, Steffen O, Strandberg B, Strakovsky II, Strub T, Supek I, Taragin MF, Thiel A, Thiel M, Tiator L, Thomas A, Unverzagt M, Wagner S, Watts DP, Werthmüller D, Wettig J, Witthauer L, Wolfes M, Workman RL, Zana L. Study of η and η' Photoproduction at MAMI. Phys Rev Lett 2017; 118:212001. [PMID: 28598665 DOI: 10.1103/physrevlett.118.212001] [Citation(s) in RCA: 2] [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: 12/23/2016] [Indexed: 06/07/2023]
Abstract
The reactions γp→ηp and γp→η^{'}p are measured from their thresholds up to the center-of-mass energy W=1.96 GeV with the tagged-photon facilities at the Mainz Microtron, MAMI. Differential cross sections are obtained with unprecedented statistical accuracy, providing fine energy binning and full production-angle coverage. A strong cusp is observed in the total cross section for η photoproduction at the energies in the vicinity of the η^{'} threshold, W=1896 MeV (E_{γ}=1447 MeV). Within the framework of a revised ηMAID isobar model, the cusp, in connection with a steep rise of the η^{'} total cross section from its threshold, can only be explained by a strong coupling of the poorly known N(1895)1/2^{-} state to both ηp and η^{'}p. Including the new high-accuracy results in the ηMAID fit to available η and η^{'} photoproduction data allows the determination of the N(1895)1/2^{-} properties.
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Affiliation(s)
- V L Kashevarov
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - P Ott
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - S Prakhov
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- The George Washington University, Washington, D.C. 20052-0001, USA
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - P Adlarson
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - F Afzal
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | - Z Ahmed
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - C S Akondi
- Kent State University, Kent, Ohio 44242-0001, USA
| | - J R M Annand
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H J Arends
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - R Beck
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | | | - W J Briscoe
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - F Cividini
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - R Codling
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - C Collicott
- Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Department of Astronomy and Physics, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - S Costanza
- INFN Sezione di Pavia, I-27100 Pavia, Italy
- Dipartimento di Fisica, Università di Pavia, I-27100 Pavia, Italy
| | - A Denig
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - E J Downie
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - M Dieterle
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - M I Ferretti Bondy
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - L V Fil'kov
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - A Fix
- Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634034 Tomsk, Russia
| | - S Gardner
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - S Garni
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - D I Glazier
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Glowa
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - W Gradl
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - G Gurevich
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - D J Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D Hornidge
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - D Howdle
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - A Käser
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - S Kay
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - I Keshelashvili
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - R Kondratiev
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - M Korolija
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - B Krusche
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - J Linturi
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - V Lisin
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - K Livingston
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - I J D MacGregor
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - R MacRae
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - J Mancell
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D M Manley
- Kent State University, Kent, Ohio 44242-0001, USA
| | - P P Martel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - J C McGeorge
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - E McNicol
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D G Middleton
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - R Miskimen
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - E Mornacchi
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - C Mullen
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - A Mushkarenkov
- INFN Sezione di Pavia, I-27100 Pavia, Italy
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - A Neiser
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Oberle
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - M Ostrick
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - P B Otte
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - B Oussena
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - D Paudyal
- University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - P Pedroni
- INFN Sezione di Pavia, I-27100 Pavia, Italy
| | | | - A Rajabi
- University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - G Reicherz
- Institut für Experimentalphysik, Ruhr-Universität, D-44780 Bochum, Germany
| | - J Robinson
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - G Rosner
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - T Rostomyan
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - A Sarty
- Department of Astronomy and Physics, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - D M Schott
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - S Schumann
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - C Sfienti
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - V Sokhoyan
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - K Spieker
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | - O Steffen
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - B Strandberg
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - I I Strakovsky
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - Th Strub
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - I Supek
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - M F Taragin
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - A Thiel
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | - M Thiel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - L Tiator
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - A Thomas
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Unverzagt
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - S Wagner
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - D P Watts
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Werthmüller
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - J Wettig
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - L Witthauer
- Departement für Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - M Wolfes
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - R L Workman
- The George Washington University, Washington, D.C. 20052-0001, USA
| | - L Zana
- SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
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4
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Martel PP, Miskimen R, Aguar-Bartolome P, Ahrens J, Akondi CS, Annand JRM, Arends HJ, Barnes W, Beck R, Bernstein A, Borisov N, Braghieri A, Briscoe WJ, Cherepnya S, Collicott C, Costanza S, Denig A, Dieterle M, Downie EJ, Fil'kov LV, Garni S, Glazier DI, Gradl W, Gurevich G, Hall Barrientos P, Hamilton D, Hornidge D, Howdle D, Huber GM, Jude TC, Kaeser A, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Krusche B, Lazarev A, Lisin V, Livingston K, MacGregor IJD, Mancell J, Manley DM, Meyer W, Middleton DG, Mushkarenkov A, Nefkens BMK, Neganov A, Nikolaev A, Oberle M, Ortega Spina H, Ostrick M, Ott P, Otte PB, Oussena B, Pedroni P, Polonski A, Polyansky V, Prakhov S, Rajabi A, Reicherz G, Rostomyan T, Sarty A, Schrauf S, Schumann S, Sikora MH, Starostin A, Steffen O, Strakovsky II, Strub T, Supek I, Thiel M, Tiator L, Thomas A, Unverzagt M, Usov Y, Watts DP, Witthauer L, Werthmüller D, Wolfes M. Measurements of double-polarized compton scattering asymmetries and extraction of the proton spin polarizabilities. Phys Rev Lett 2015; 114:112501. [PMID: 25839263 DOI: 10.1103/physrevlett.114.112501] [Citation(s) in RCA: 6] [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: 08/06/2014] [Indexed: 06/04/2023]
Abstract
The spin polarizabilities of the nucleon describe how the spin of the nucleon responds to an incident polarized photon. The most model-independent way to extract the nucleon spin polarizabilities is through polarized Compton scattering. Double-polarized Compton scattering asymmetries on the proton were measured in the Δ(1232) region using circularly polarized incident photons and a transversely polarized proton target at the Mainz Microtron. Fits to asymmetry data were performed using a dispersion model calculation and a baryon chiral perturbation theory calculation, and a separation of all four proton spin polarizabilities in the multipole basis was achieved. The analysis based on a dispersion model calculation yields γ(E1E1)=-3.5±1.2, γ(M1M1)=3.16±0.85, γ(E1M2)=-0.7±1.2, and γ(M1E2)=1.99±0.29, in units of 10(-4) fm(4).
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Affiliation(s)
- P P Martel
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
- Department of Physics, Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - R Miskimen
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
| | | | - J Ahrens
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - C S Akondi
- Department of Physics, Kent State University, Kent, Ohio 44242, USA
| | - J R M Annand
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H J Arends
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - W Barnes
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
| | - R Beck
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | - A Bernstein
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - N Borisov
- Joint Institute for Nuclear Research (JINR), 141980 Dubna, Russia
| | | | - W J Briscoe
- Department of Physics, The George Washington University, Washington, D.C. 20052, USA
| | - S Cherepnya
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - C Collicott
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Department of Astronomy and Physics, Saint Marys University, Halifax, Nova Scotia B3H 3C3, Canada
| | - S Costanza
- INFN Sezione di Pavia, I-27100 Pavia, Italy
| | - A Denig
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - M Dieterle
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - E J Downie
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
- Department of Physics, The George Washington University, Washington, D.C. 20052, USA
| | - L V Fil'kov
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - S Garni
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - D I Glazier
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
- School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - W Gradl
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - G Gurevich
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - P Hall Barrientos
- School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Hamilton
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D Hornidge
- Department of Physics, Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - D Howdle
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - G M Huber
- Department of Physics, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - T C Jude
- School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - A Kaeser
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | | | - I Keshelashvili
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - R Kondratiev
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - M Korolija
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - B Krusche
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - A Lazarev
- Joint Institute for Nuclear Research (JINR), 141980 Dubna, Russia
| | - V Lisin
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - K Livingston
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - I J D MacGregor
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - J Mancell
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D M Manley
- Department of Physics, Kent State University, Kent, Ohio 44242, USA
| | - W Meyer
- Institut für Experimentalphysik, Ruhr-Universität, D-44780 Bochum, Germany
| | - D G Middleton
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
- Department of Physics, Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - A Mushkarenkov
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
| | - B M K Nefkens
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - A Neganov
- Joint Institute for Nuclear Research (JINR), 141980 Dubna, Russia
| | - A Nikolaev
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | - M Oberle
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - H Ortega Spina
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - M Ostrick
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - P Ott
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - P B Otte
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - B Oussena
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - P Pedroni
- INFN Sezione di Pavia, I-27100 Pavia, Italy
| | - A Polonski
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - V Polyansky
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - S Prakhov
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
- Department of Physics, The George Washington University, Washington, D.C. 20052, USA
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - A Rajabi
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
| | - G Reicherz
- Institut für Experimentalphysik, Ruhr-Universität, D-44780 Bochum, Germany
| | - T Rostomyan
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - A Sarty
- Department of Astronomy and Physics, Saint Marys University, Halifax, Nova Scotia B3H 3C3, Canada
| | - S Schrauf
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - S Schumann
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - M H Sikora
- School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - A Starostin
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - O Steffen
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - I I Strakovsky
- Department of Physics, The George Washington University, Washington, D.C. 20052, USA
| | - T Strub
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - I Supek
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - M Thiel
- II. Physikalisches Institut, Universität Giessen, D-35392 Giessen, Germany
| | - L Tiator
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - A Thomas
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
| | - M Unverzagt
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
- Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn, Germany
| | - Y Usov
- Joint Institute for Nuclear Research (JINR), 141980 Dubna, Russia
| | - D P Watts
- School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - L Witthauer
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - D Werthmüller
- Departement Physik, Universität Basel, CH-4056 Basel, Switzerland
| | - M Wolfes
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
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5
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Myers LS, Annand JRM, Brudvik J, Feldman G, Fissum KG, Grießhammer HW, Hansen K, Henshaw SS, Isaksson L, Jebali R, Kovash MA, Lundin M, McGovern JA, Middleton DG, Nathan AM, Phillips DR, Schröder B, Stave SC. Measurement of Compton scattering from the deuteron and an improved extraction of the neutron electromagnetic polarizabilities. Phys Rev Lett 2014; 113:262506. [PMID: 25615318 DOI: 10.1103/physrevlett.113.262506] [Citation(s) in RCA: 4] [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: 09/19/2014] [Indexed: 06/04/2023]
Abstract
The electromagnetic polarizabilities of the nucleon are fundamental properties that describe its response to external electric and magnetic fields. They can be extracted from Compton-scattering data-and have been, with good accuracy, in the case of the proton. In contradistinction, information for the neutron requires the use of Compton scattering from nuclear targets. Here, we report a new measurement of elastic photon scattering from deuterium using quasimonoenergetic tagged photons at the MAX IV Laboratory in Lund, Sweden. These first new data in more than a decade effectively double the world data set. Their energy range overlaps with previous experiments and extends it by 20 MeV to higher energies. An analysis using chiral effective field theory with dynamical Δ(1232) degrees of freedom shows the data are consistent with and within the world data set. After demonstrating that the fit is consistent with the Baldin sum rule, extracting values for the isoscalar nucleon polarizabilities, and combining them with a recent result for the proton, we obtain the neutron polarizabilities as αn=[11.55±1.25(stat)±0.2(BSR)±0.8(th)]×10(-4) fm(3) and βn=[3.65∓1.25(stat)±0.2(BSR)∓0.8(th)]×10(-4) fm(3), with χ(2)=45.2 for 44 degrees of freedom.
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Affiliation(s)
- L S Myers
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - J R M Annand
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - J Brudvik
- MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden
| | - G Feldman
- Institute for Nuclear Studies, Department of Physics, The George Washington University, Washington, DC 20052, USA
| | - K G Fissum
- Department of Physics, Lund University, SE-221 00 Lund, Sweden
| | - H W Grießhammer
- Institute for Nuclear Studies, Department of Physics, The George Washington University, Washington, DC 20052, USA
| | - K Hansen
- MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden
| | - S S Henshaw
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - L Isaksson
- MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden
| | - R Jebali
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - M A Kovash
- Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA
| | - M Lundin
- MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden
| | - J A McGovern
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - D G Middleton
- Kepler Centre for Astro- and Particle Physics, Physikalisches Institut, Universität Tübingen, D-72076 Tübingen, Germany
| | - A M Nathan
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - D R Phillips
- Department of Physics and Astronomy and Institute of Nuclear and Particle Physics, Ohio University, Athens, Ohio 45701, USA
| | - B Schröder
- MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden and Department of Physics, Lund University, SE-221 00 Lund, Sweden
| | - S C Stave
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
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6
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Merkel H, Achenbach P, Ayerbe Gayoso C, Beranek T, Beričič J, Bernauer JC, Böhm R, Bosnar D, Correa L, Debenjak L, Denig A, Distler MO, Esser A, Fonvieille H, Friščić I, Gómez Rodríguez de la Paz M, Hoek M, Kegel S, Kohl Y, Middleton DG, Mihovilovič M, Müller U, Nungesser L, Pochodzalla J, Rohrbeck M, Ron G, Sánchez Majos S, Schlimme BS, Schoth M, Schulz F, Sfienti C, Sirca S, Thiel M, Tyukin A, Weber A, Weinriefer M. Search at the Mainz Microtron for light massive gauge bosons relevant for the muon g-2 anomaly. Phys Rev Lett 2014; 112:221802. [PMID: 24949757 DOI: 10.1103/physrevlett.112.221802] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Indexed: 06/03/2023]
Abstract
A massive, but light, Abelian U(1) gauge boson is a well-motivated possible signature of physics beyond the standard model of particle physics. In this Letter, the search for the signal of such a U(1) gauge boson in electron-positron pair production at the spectrometer setup of the A1 Collaboration at the Mainz Microtron is described. Exclusion limits in the mass range of 40 MeV/c^{2} to 300 MeV/c^{2}, with a sensitivity in the squared mixing parameter of as little as ε^{2}=8×10^{-7} are presented. A large fraction of the parameter space has been excluded where the discrepancy of the measured anomalous magnetic moment of the muon with theory might be explained by an additional U(1) gauge boson.
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Affiliation(s)
- H Merkel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - P Achenbach
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - C Ayerbe Gayoso
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - T Beranek
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - J Beričič
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - J C Bernauer
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - R Böhm
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - D Bosnar
- Department of Physics, University of Zagreb, HR-10002 Zagreb, Croatia
| | - L Correa
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - L Debenjak
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - A Denig
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M O Distler
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - A Esser
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - H Fonvieille
- Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, BP 10448, F-63000 Clermont-Ferrand, France
| | - I Friščić
- Department of Physics, University of Zagreb, HR-10002 Zagreb, Croatia
| | | | - M Hoek
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - S Kegel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - Y Kohl
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - D G Middleton
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Mihovilovič
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - U Müller
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - L Nungesser
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - J Pochodzalla
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Rohrbeck
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - G Ron
- Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - S Sánchez Majos
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - B S Schlimme
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Schoth
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - F Schulz
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - C Sfienti
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - S Sirca
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia and Department of Physics, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - M Thiel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - A Tyukin
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - A Weber
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
| | - M Weinriefer
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
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7
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Mihovilovič M, Merkel H, Weber A, Achenbach P, Ayerbe Gayoso C, Beranek T, Beričič J, Bernauer JC, Bosnar D, Böhm R, Correa L, Debenjak L, Denig A, Distler MO, Esser A, Fonvieille H, Friščić I, Gómez M, Kegel S, Kohl Y, Middleton DG, Müller U, Nungesser L, Pochodzalla J, Rohrbeck M, Sánchez Majos S, Schlimme BS, Schoth M, Schulz F, Sfienti C, Širca S, Štajner S, Thiel M, Weinriefer M. Initial state radiation experiment at MAMI. EPJ Web of Conferences 2014. [DOI: 10.1051/epjconf/20147200017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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8
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Dieterle M, Keshelashvili I, Ahrens J, Annand JRM, Arends HJ, Bantawa K, Bartolome PA, Beck R, Bekrenev V, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Demissie B, Downie EJ, Drexler P, Fil'kov LV, Fix A, Glazier DI, Hamilton D, Heid E, Hornidge D, Howdle D, Huber GM, Jaegle I, Jahn O, Jude TC, Käser A, Kashevarov VL, Kondratiev R, Korolija M, Kruglov SP, Krusche B, Kulbardis A, Lisin V, Livingston K, MacGregor IJD, Maghrbi Y, Mancell J, Manley DM, Marinides Z, Martinez M, McGeorge JC, McNicoll E, Mekterovic D, Metag V, Micanovic S, Middleton DG, Mushkarenkov A, Nefkens BMK, Nikolaev A, Novotny R, Oberle M, Ostrick M, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov SN, Robinson J, Rosner G, Rostomyan T, Schumann S, Sikora MH, Sober D, Starostin A, Supek I, Thiel M, Thomas A, Unverzagt M, Watts DP, Werthmüller D, Witthauer L. Photoproduction of π0 mesons off neutrons in the nucleon resonance region. Phys Rev Lett 2014; 112:142001. [PMID: 24765945 DOI: 10.1103/physrevlett.112.142001] [Citation(s) in RCA: 3] [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: 10/08/2013] [Indexed: 06/03/2023]
Abstract
Precise angular distributions have been measured for the first time for the photoproduction of π0 mesons off neutrons bound in the deuteron. The effects from nuclear Fermi motion have been eliminated by a complete kinematic reconstruction of the final state. The influence of final-state-interaction effects has been estimated by a comparison of the reaction cross section for quasifree protons bound in the deuteron to the results for free protons and then applied as a correction to the quasifree neutron data. The experiment was performed at the tagged photon facility of the Mainz Microtron MAMI with the Crystal Ball and TAPS detector setup for incident photon energies between 0.45 and 1.4 GeV. The results are compared to the predictions from reaction models and partial-wave analyses based on data from other isospin channels. The model predictions show large discrepancies among each other and the present data will provide much tighter constraints. This is demonstrated by the results of a new analysis in the framework of the Bonn-Gatchina coupled-channel analysis which included the present data.
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Affiliation(s)
- M Dieterle
- Department of Physics, University of Basel, Switzerland
| | | | - J Ahrens
- Institut für Kernphysik, University of Mainz, Germany
| | - J R M Annand
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - H J Arends
- Institut für Kernphysik, University of Mainz, Germany
| | - K Bantawa
- Kent State University, Kent, Ohio, USA
| | - P A Bartolome
- Institut für Kernphysik, University of Mainz, Germany
| | - R Beck
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University of Bonn, Germany
| | - V Bekrenev
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | | | - D Branford
- School of Physics, University of Edinburgh, Edinburgh, United Kingdom
| | - W J Briscoe
- Center for Nuclear Studies, The George Washington University, Washington, DC, USA
| | - J Brudvik
- University of California at Los Angeles, Los Angeles, California, USA
| | | | - B Demissie
- Center for Nuclear Studies, The George Washington University, Washington, DC, USA
| | - E J Downie
- Institut für Kernphysik, University of Mainz, Germany and Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom and Center for Nuclear Studies, The George Washington University, Washington, DC, USA
| | - P Drexler
- II. Physikalisches Institut, University of Giessen, Germany
| | | | - A Fix
- Laboratory of Mathematical Physics, Tomsk Polytechnic University, Tomsk, Russia
| | - D I Glazier
- School of Physics, University of Edinburgh, Edinburgh, United Kingdom
| | - D Hamilton
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - E Heid
- Institut für Kernphysik, University of Mainz, Germany
| | - D Hornidge
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - D Howdle
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - G M Huber
- University of Regina, Regina, Saskatchewan S4S 0A2 Canada
| | - I Jaegle
- Department of Physics, University of Basel, Switzerland
| | - O Jahn
- Institut für Kernphysik, University of Mainz, Germany
| | - T C Jude
- School of Physics, University of Edinburgh, Edinburgh, United Kingdom
| | - A Käser
- Department of Physics, University of Basel, Switzerland
| | - V L Kashevarov
- Institut für Kernphysik, University of Mainz, Germany and Lebedev Physical Institute, Moscow, Russia
| | | | - M Korolija
- Rudjer Boskovic Institute, Zagreb, Croatia
| | - S P Kruglov
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | - B Krusche
- Department of Physics, University of Basel, Switzerland
| | - A Kulbardis
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | - V Lisin
- Institute for Nuclear Research, Moscow, Russia
| | - K Livingston
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - I J D MacGregor
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - Y Maghrbi
- Department of Physics, University of Basel, Switzerland
| | - J Mancell
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | | | - Z Marinides
- Center for Nuclear Studies, The George Washington University, Washington, DC, USA
| | - M Martinez
- Institut für Kernphysik, University of Mainz, Germany
| | - J C McGeorge
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - E McNicoll
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | | | - V Metag
- II. Physikalisches Institut, University of Giessen, Germany
| | | | - D G Middleton
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | | | - B M K Nefkens
- University of California at Los Angeles, Los Angeles, California, USA
| | - A Nikolaev
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University of Bonn, Germany
| | - R Novotny
- II. Physikalisches Institut, University of Giessen, Germany
| | - M Oberle
- Department of Physics, University of Basel, Switzerland
| | - M Ostrick
- Institut für Kernphysik, University of Mainz, Germany
| | - B Oussena
- Institut für Kernphysik, University of Mainz, Germany and Center for Nuclear Studies, The George Washington University, Washington, DC, USA
| | | | - F Pheron
- Department of Physics, University of Basel, Switzerland
| | - A Polonski
- Institute for Nuclear Research, Moscow, Russia
| | - S N Prakhov
- University of California at Los Angeles, Los Angeles, California, USA
| | - J Robinson
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - G Rosner
- Department of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
| | - T Rostomyan
- Department of Physics, University of Basel, Switzerland
| | - S Schumann
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University of Bonn, Germany
| | - M H Sikora
- School of Physics, University of Edinburgh, Edinburgh, United Kingdom
| | - D Sober
- The Catholic University of America, Washington, DC, USA
| | - A Starostin
- University of California at Los Angeles, Los Angeles, California, USA
| | - I Supek
- Rudjer Boskovic Institute, Zagreb, Croatia
| | - M Thiel
- Institut für Kernphysik, University of Mainz, Germany and II. Physikalisches Institut, University of Giessen, Germany
| | - A Thomas
- Institut für Kernphysik, University of Mainz, Germany
| | - M Unverzagt
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University of Bonn, Germany
| | - D P Watts
- School of Physics, University of Edinburgh, Edinburgh, United Kingdom
| | - D Werthmüller
- Department of Physics, University of Basel, Switzerland
| | - L Witthauer
- Department of Physics, University of Basel, Switzerland
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9
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Sikora MH, Watts DP, Glazier DI, Aguar-Bartolomé P, Akasoy LK, Annand JRM, Arends HJ, Bantawa K, Beck R, Bekrenev VS, Berghäuser H, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Codling RFB, Demissie BT, Downie EJ, Drexler P, Fil'kov LV, Freehart B, Gregor R, Hamilton D, Heid E, Hornidge D, Howdle DA, Jaegle I, Jahn O, Jude TC, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Kotulla M, Koulbardis AA, Kruglov SP, Krusche B, Lisin V, Livingston K, MacGregor IJD, Maghrbi Y, Manley DM, Marinides Z, Martinez M, McGeorge JC, McKinnon B, McNicoll EF, Mekterovic D, Metag V, Micanovic S, Middleton DG, Mushkarenkov A, Nefkens BMK, Nikolaev A, Novotny R, Ostrick M, Otte PB, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov S, Robinson J, Rosner G, Rostomyan T, Schumann S, Sober DI, Starostin A, Strakovsky II, Suarez IM, Supek I, Thiel M, Thomas A, Unverzagt M, Werthmüller D, Workman RL, Zamboni I, Zehr F. Measurement of the 1H(γ, p)π0 reaction using a novel nucleon spin polarimeter. Phys Rev Lett 2014; 112:022501. [PMID: 24484003 DOI: 10.1103/physrevlett.112.022501] [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: 09/12/2013] [Indexed: 06/03/2023]
Abstract
We report the first large-acceptance measurement of polarization transfer from a polarized photon beam to a recoiling nucleon. The measurement pioneers a novel polarimetry technique, which can be applied to many other nuclear and hadron physics experiments. The commissioning reaction of 1H(γ, p)π0 in the range 0.4<Eγ<1.4 GeV validates the technique and provides essential new data to constrain the excitation spectrum of the nucleon.
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Affiliation(s)
- M H Sikora
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D P Watts
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D I Glazier
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - P Aguar-Bartolomé
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - L K Akasoy
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - J R M Annand
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H J Arends
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - K Bantawa
- Kent State University, Kent, Ohio 44242, USA
| | - R Beck
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, D-53115 Bonn, Germany
| | - V S Bekrenev
- Petersburg Nuclear Physics Institute, 188300 Gatchina, Russia
| | - H Berghäuser
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | | | - D Branford
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - W J Briscoe
- The George Washington University, Washington, D.C. 20052, USA
| | - J Brudvik
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - S Cherepnya
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - R F B Codling
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - B T Demissie
- The George Washington University, Washington, D.C. 20052, USA
| | - E J Downie
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany and SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom and The George Washington University, Washington, D.C. 20052, USA
| | - P Drexler
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - L V Fil'kov
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - B Freehart
- The George Washington University, Washington, D.C. 20052, USA
| | - R Gregor
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - D Hamilton
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - E Heid
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany and The George Washington University, Washington, D.C. 20052, USA
| | - D Hornidge
- Mount Allison University, Sackville, New Brunswick E4L3B5, Canada
| | - D A Howdle
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - I Jaegle
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
| | - O Jahn
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - T C Jude
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | | | - I Keshelashvili
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
| | - R Kondratiev
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - M Korolija
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - M Kotulla
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - A A Koulbardis
- Petersburg Nuclear Physics Institute, 188300 Gatchina, Russia
| | - S P Kruglov
- Petersburg Nuclear Physics Institute, 188300 Gatchina, Russia
| | - B Krusche
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
| | - V Lisin
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - K Livingston
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - I J D MacGregor
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Y Maghrbi
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
| | - D M Manley
- Kent State University, Kent, Ohio 44242, USA
| | - Z Marinides
- The George Washington University, Washington, D.C. 20052, USA
| | - M Martinez
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - J C McGeorge
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - B McKinnon
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - E F McNicoll
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D Mekterovic
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - V Metag
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - S Micanovic
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - D G Middleton
- Mount Allison University, Sackville, New Brunswick E4L3B5, Canada
| | | | - B M K Nefkens
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - A Nikolaev
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, D-53115 Bonn, Germany
| | - R Novotny
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - M Ostrick
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - P B Otte
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - B Oussena
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany and The George Washington University, Washington, D.C. 20052, USA
| | - P Pedroni
- INFN Sezione di Pavia, I-27100 Pavia, Italy
| | - F Pheron
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
| | - A Polonski
- Institute for Nuclear Research, 125047 Moscow, Russia
| | - S Prakhov
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - J Robinson
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - G Rosner
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | | | - S Schumann
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - D I Sober
- The Catholic University of America, Washington D.C. 20064, USA
| | - A Starostin
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - I I Strakovsky
- The George Washington University, Washington, D.C. 20052, USA
| | - I M Suarez
- University of California Los Angeles, Los Angeles, California 90095-1547, USA
| | - I Supek
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - M Thiel
- II Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany
| | - A Thomas
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - M Unverzagt
- Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany
| | - D Werthmüller
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
| | - R L Workman
- The George Washington University, Washington, D.C. 20052, USA
| | - I Zamboni
- Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia
| | - F Zehr
- Department Physik, University of Basel, CH-4056 Basel, Switzerland
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10
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Werthmüller D, Witthauer L, Keshelashvili I, Aguar-Bartolomé P, Ahrens J, Annand JRM, Arends HJ, Bantawa K, Beck R, Bekrenev V, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Demissie B, Dieterle M, Downie EJ, Drexler P, Fil'kov LV, Fix A, Glazier DI, Hamilton D, Heid E, Hornidge D, Howdle D, Huber GM, Jaegle I, Jahn O, Jude TC, Käser A, Kashevarov VL, Kondratiev R, Korolija M, Kruglov SP, Krusche B, Kulbardis A, Lisin V, Livingston K, MacGregor IJD, Maghrbi Y, Mancell J, Manley DM, Marinides Z, Martinez M, McGeorge JC, McNicoll EF, Metag V, Middleton DG, Mushkarenkov A, Nefkens BMK, Nikolaev A, Novotny R, Oberle M, Ostrick M, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov SN, Robinson J, Rosner G, Rostomyan T, Schumann S, Sikora MH, Sober D, Starostin A, Supek I, Thiel M, Thomas A, Unverzagt M, Watts DP. Narrow structure in the excitation function of η photoproduction off the neutron. Phys Rev Lett 2013; 111:232001. [PMID: 24476257 DOI: 10.1103/physrevlett.111.232001] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 10/28/2013] [Indexed: 06/03/2023]
Abstract
The photoproduction of η mesons off nucleons bound in 2H and 3He has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the η→2γ and η→3π0 decays and the recoil nucleons were detected with an almost 4π electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of γn→nη. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W=(1670±5) MeV and Γ=(30±15) MeV. For the first time precise results for the angular dependence of this structure have been extracted.
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Affiliation(s)
- D Werthmüller
- Departement für Physik, Universität Basel, Switzerland
| | - L Witthauer
- Departement für Physik, Universität Basel, Switzerland
| | | | | | - J Ahrens
- Institut für Kernphysik, Universität Mainz, Germany
| | - J R M Annand
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H J Arends
- Institut für Kernphysik, Universität Mainz, Germany
| | - K Bantawa
- Kent State University, Kent, Ohio, USA
| | - R Beck
- Institut für Kernphysik, Universität Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, Germany
| | - V Bekrenev
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | | | - D Branford
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - W J Briscoe
- Institute for Nuclear Studies, The George Washington University, Washington, District of Columbia, USA
| | - J Brudvik
- University of California at Los Angeles, Los Angeles, California, USA
| | | | - B Demissie
- Institute for Nuclear Studies, The George Washington University, Washington, District of Columbia, USA
| | - M Dieterle
- Departement für Physik, Universität Basel, Switzerland
| | - E J Downie
- Institut für Kernphysik, Universität Mainz, Germany and SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom and Institute for Nuclear Studies, The George Washington University, Washington, District of Columbia, USA
| | - P Drexler
- II. Physikalisches Institut, Universität Giessen, Germany
| | | | - A Fix
- Laboratory of Mathematical Physics, Tomsk Polytechnic University, Tomsk, Russia
| | - D I Glazier
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Hamilton
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - E Heid
- Institut für Kernphysik, Universität Mainz, Germany
| | - D Hornidge
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - D Howdle
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - G M Huber
- University of Regina, Regina, SK S4S 0A2, Canada
| | - I Jaegle
- Departement für Physik, Universität Basel, Switzerland
| | - O Jahn
- Institut für Kernphysik, Universität Mainz, Germany
| | - T C Jude
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - A Käser
- Departement für Physik, Universität Basel, Switzerland
| | - V L Kashevarov
- Institut für Kernphysik, Universität Mainz, Germany and Lebedev Physical Institute, Moscow, Russia
| | | | - M Korolija
- Rudjer Boskovic Institute, Zagreb, Croatia
| | - S P Kruglov
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | - B Krusche
- Departement für Physik, Universität Basel, Switzerland
| | - A Kulbardis
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | - V Lisin
- Institute for Nuclear Research, Moscow, Russia
| | - K Livingston
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - I J D MacGregor
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Y Maghrbi
- Departement für Physik, Universität Basel, Switzerland
| | - J Mancell
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | | | - Z Marinides
- Institute for Nuclear Studies, The George Washington University, Washington, District of Columbia, USA
| | - M Martinez
- Institut für Kernphysik, Universität Mainz, Germany
| | - J C McGeorge
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - E F McNicoll
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - V Metag
- II. Physikalisches Institut, Universität Giessen, Germany
| | - D G Middleton
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | | | - B M K Nefkens
- University of California at Los Angeles, Los Angeles, California, USA
| | - A Nikolaev
- Institut für Kernphysik, Universität Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, Germany
| | - R Novotny
- II. Physikalisches Institut, Universität Giessen, Germany
| | - M Oberle
- Departement für Physik, Universität Basel, Switzerland
| | - M Ostrick
- Institut für Kernphysik, Universität Mainz, Germany
| | - B Oussena
- Institut für Kernphysik, Universität Mainz, Germany and Institute for Nuclear Studies, The George Washington University, Washington, District of Columbia, USA
| | | | - F Pheron
- Departement für Physik, Universität Basel, Switzerland
| | - A Polonski
- Institute for Nuclear Research, Moscow, Russia
| | - S N Prakhov
- Institut für Kernphysik, Universität Mainz, Germany and Institute for Nuclear Studies, The George Washington University, Washington, District of Columbia, USA and University of California at Los Angeles, Los Angeles, California, USA
| | - J Robinson
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - G Rosner
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - T Rostomyan
- Departement für Physik, Universität Basel, Switzerland
| | - S Schumann
- Institut für Kernphysik, Universität Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, Germany
| | - M H Sikora
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - D Sober
- The Catholic University of America, Washington, District of Columbia, USA
| | - A Starostin
- University of California at Los Angeles, Los Angeles, California, USA
| | - I Supek
- Rudjer Boskovic Institute, Zagreb, Croatia
| | - M Thiel
- Institut für Kernphysik, Universität Mainz, Germany and II. Physikalisches Institut, Universität Giessen, Germany
| | - A Thomas
- Institut für Kernphysik, Universität Mainz, Germany
| | - M Unverzagt
- Institut für Kernphysik, Universität Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, Germany
| | - D P Watts
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
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Schlimme BS, Achenbach P, Ayerbe Gayoso CA, Bernauer JC, Böhm R, Bosnar D, Challand T, Distler MO, Doria L, Fellenberger F, Fonvieille H, Gómez Rodríguez M, Grabmayr P, Hehl T, Heil W, Kiselev D, Krimmer J, Makek M, Merkel H, Middleton DG, Müller U, Nungesser L, Ott BA, Pochodzalla J, Potokar M, Sánchez Majos S, Sargsian MM, Sick I, Sirca S, Weinriefer M, Wendel M, Yoon CJ. Measurement of the neutron electric to magnetic form factor ratio at Q2=1.58 GeV2 using the reaction 3He[over →](e[over →],e'n)pp. Phys Rev Lett 2013; 111:132504. [PMID: 24116774 DOI: 10.1103/physrevlett.111.132504] [Citation(s) in RCA: 4] [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: 07/30/2013] [Indexed: 06/02/2023]
Abstract
A measurement of beam helicity asymmetries in the reaction 3He[over →](e[over →],e'n)pp is performed at the Mainz Microtron in quasielastic kinematics to determine the electric to magnetic form factor ratio of the neutron GEn/GMn at a four-momentum transfer Q2=1.58 GeV2. Longitudinally polarized electrons are scattered on a highly polarized 3He gas target. The scattered electrons are detected with a high-resolution magnetic spectrometer, and the ejected neutrons are detected with a dedicated neutron detector composed of scintillator bars. To reduce systematic errors, data are taken for four different target polarization orientations allowing the determination of GEn/GMn from a double ratio. We find μnGEn/GMn=0.250±0.058(stat)±0.017(syst).
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Affiliation(s)
- B S Schlimme
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
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12
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Hornidge D, Aguar Bartolomé P, Annand JRM, Arends HJ, Beck R, Bekrenev V, Berghäuser H, Bernstein AM, Braghieri A, Briscoe WJ, Cherepnya S, Dieterle M, Downie EJ, Drexler P, Fernández-Ramírez C, Filkov LV, Glazier DI, Hall Barrientos P, Heid E, Hilt M, Jaegle I, Jahn O, Jude TC, Kashevarov VL, Keshelashvili I, Kondratiev R, Korolija M, Koulbardis A, Krambrich D, Kruglov S, Krusche B, Laffoley AT, Lisin V, Livingston K, MacGregor IJD, Mancell J, Manley DM, McNicoll EF, Mekterovic D, Metag V, Micanovic S, Middleton DG, Moores KW, Mushkarenkov A, Nefkens BMK, Oberle M, Ostrick M, Otte PB, Oussena B, Pedroni P, Pheron F, Polonski A, Prakhov S, Robinson J, Rostomyan T, Scherer S, Schumann S, Sikora MH, Starostin A, Supek I, Thiel M, Thomas A, Tiator L, Unverzagt M, Watts DP, Werthmüller D, Witthauer L. Accurate test of chiral dynamics in the γp→π0p reaction. Phys Rev Lett 2013; 111:062004. [PMID: 23971564 DOI: 10.1103/physrevlett.111.062004] [Citation(s) in RCA: 3] [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: 11/23/2012] [Indexed: 06/02/2023]
Abstract
A precision measurement of the differential cross sections dσ/dΩ and the linearly polarized photon asymmetry Σ≡(dσ⊥-dσ∥)/(dσ⊥+dσ∥) for the γp→π0p reaction in the near-threshold region has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The Glasgow-Mainz photon tagging facility along with the Crystal Ball/TAPS multiphoton detector system and a cryogenic liquid hydrogen target were used. These data allowed for a precise determination of the energy dependence of the real parts of the S- and all three P-wave amplitudes for the first time and provide the most stringent test to date of the predictions of chiral perturbation theory and its energy region of agreement with experiment.
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Affiliation(s)
- D Hornidge
- Mount Allison University, Sackville, New Brunswick, E4L 1E6, Canada.
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13
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Sfienti C, Achenbach P, Ayerbe Gayoso C, Böhm R, Bosnar D, Debenjak L, Denig A, Distler MO, Esser A, Fonvieille H, Friščic I, Fujii Y, Gogami T, Mar Gòmez R, Hashimoto H, Hirose S, Merkel H, Middleton DG, Molitor M, Müller U, Nungesser L, Nagao S, Nakamura SN, Pochodzalla J, Saito T, Sànchez Majos S, Sanchez Lorente A, Schlimme BS, Schoth M, Schulz F, Širca S, Tang L, Thiel M, Tsukada K, Walcher T. The frontiers of the virtual photons program at MAMI. EPJ Web of Conferences 2012. [DOI: 10.1051/epjconf/20123701015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Merkel H, Achenbach P, Ayerbe Gayoso C, Bernauer JC, Böhm R, Bosnar D, Debenjak L, Denig A, Distler MO, Esser A, Fonvieille H, Friščić I, Middleton DG, Müller U, Nungesser L, Pochodzalla J, Rohrbeck M, Sánchez Majos S, Schlimme BS, Schoth M, Sirca S, Weinriefer M. Search for light gauge bosons of the dark sector at the Mainz Microtron. Phys Rev Lett 2011; 106:251802. [PMID: 21770630 DOI: 10.1103/physrevlett.106.251802] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Indexed: 05/31/2023]
Abstract
A new exclusion limit for the electromagnetic production of a light U(1) gauge boson γ' decaying to e + e- was determined by the A1 Collaboration at the Mainz Microtron. Such light gauge bosons appear in several extensions of the standard model and are also discussed as candidates for the interaction of dark matter with standard model matter. In electron scattering from a heavy nucleus, the existing limits for a narrow state coupling to e + e- were reduced by nearly an order of magnitude in the range of the lepton pair mass of 210 MeV/c2}<me +}e-<300 MeV/c2. This experiment demonstrates the potential of high current and high resolution fixed target experiments for the search for physics beyond the standard model.
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Affiliation(s)
- H Merkel
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany
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15
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Bernauer JC, Achenbach P, Ayerbe Gayoso C, Böhm R, Bosnar D, Debenjak L, Distler MO, Doria L, Esser A, Fonvieille H, Friedrich JM, Friedrich J, Gómez Rodríguez de la Paz M, Makek M, Merkel H, Middleton DG, Müller U, Nungesser L, Pochodzalla J, Potokar M, Sánchez Majos S, Schlimme BS, Sirca S, Walcher T, Weinriefer M. High-precision determination of the electric and magnetic form factors of the proton. Phys Rev Lett 2010; 105:242001. [PMID: 21231520 DOI: 10.1103/physrevlett.105.242001] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Indexed: 05/30/2023]
Abstract
New precise results of a measurement of the elastic electron-proton scattering cross section performed at the Mainz Microtron MAMI are presented. About 1400 cross sections were measured with negative four-momentum transfers squared up to Q² = 1 (GeV/c)² with statistical errors below 0.2%. The electric and magnetic form factors of the proton were extracted by fits of a large variety of form factor models directly to the cross sections. The form factors show some features at the scale of the pion cloud. The charge and magnetic radii are determined to be <r²E>½ = 0.879(5)stat(4)syst(2)model(4)group fm and <r²M>½ = 0.777(13)stat(9)syst(5)model(2)group fm.
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Affiliation(s)
- J C Bernauer
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany.
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16
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Middleton DG, Annand JRM, Antelo MA, Ayerbe C, Barneo P, Baumann D, Bermuth J, Bernauer J, Blok HP, Böhm R, Bosnar D, Ding M, Distler MO, Friedrich J, Llongo JG, Glazier DI, Golak J, Glöckle W, Grabmayr P, Hehl T, Heim J, Hesselink WHA, Jans E, Kamada H, Mañas GJ, Kohl M, Lapikás L, MacGregor IJD, Martin I, McGeorge JC, Merkel H, Merle P, Monstad K, Moschini F, Müller U, Nogga A, Pérez-Benito R, Pospischil T, Potokar M, Rosner G, Seimetz M, Skibiński R, de Vries H, Walcher T, Watts DP, Weinriefer M, Weiss M, Witała H, Zihlmann B. Investigation of the exclusive 3He(e,e' pn)1H reaction. Phys Rev Lett 2009; 103:152501. [PMID: 19905628 DOI: 10.1103/physrevlett.103.152501] [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: 03/06/2009] [Indexed: 05/28/2023]
Abstract
Cross sections for the 3He(e,e' pn)1H reaction were measured for the first time at energy transfers of 220 and 270 MeV for several momentum transfers ranging from 300 to 450 MeV/c. Cross sections are presented as a function of the momentum of the recoil proton and the momentum transfer. Continuum Faddeev calculations using the Argonne V18 and Bonn-B nucleon-nucleon potentials overestimate the measured cross sections by a factor 5 at low recoil proton momentum with the discrepancy becoming smaller at higher recoil proton momentum.
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Affiliation(s)
- D G Middleton
- Kepler Centre for Astro and Particle Physics, Physikalisches Institut, Universität Tübingen, D-72076 Tübingen, Germany.
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17
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Middleton DG. Effect on hormone levels of heat treatment for inactivation of human immunodeficiency virus in plasma. Med Lab Sci 1988; 45:94-6. [PMID: 3200130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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18
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Middleton DG, Parker JA. The extraction of information from a noisy background by the use of stereopsis. Can J Ophthalmol 1969; 4:191-8. [PMID: 5769108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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