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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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3
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Tarbert CM, Watts DP, Glazier DI, Aguar P, Ahrens J, Annand JRM, Arends HJ, Beck R, Bekrenev V, Boillat B, Braghieri A, Branford D, Briscoe WJ, Brudvik J, Cherepnya S, Codling R, Downie EJ, Foehl K, Grabmayr P, Gregor R, Heid E, Hornidge D, Jahn O, Kashevarov VL, Knezevic A, Kondratiev R, Korolija M, Kotulla M, Krambrich D, Krusche B, Lang M, Lisin V, Livingston K, Lugert S, MacGregor IJD, Manley DM, Martinez M, McGeorge JC, Mekterovic D, Metag V, Nefkens BMK, Nikolaev A, Novotny R, Owens RO, Pedroni P, Polonski A, Prakhov SN, Price JW, Rosner G, Rost M, Rostomyan T, Schadmand S, Schumann S, Sober D, Starostin A, Supek I, Thomas A, Unverzagt M, Walcher T, Zana L, Zehr F. Neutron skin of (208)pb from coherent pion photoproduction. Phys Rev Lett 2014; 112:242502. [PMID: 24996085 DOI: 10.1103/physrevlett.112.242502] [Citation(s) in RCA: 7] [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: 02/02/2014] [Indexed: 06/03/2023]
Abstract
Information on the size and shape of the neutron skin on (208)Pb is extracted from coherent pion photoproduction cross sections measured using the Crystal Ball detector together with the Glasgow tagger at the MAMI electron beam facility. On exploitation of an interpolated fit of a theoretical model to the measured cross sections, the half-height radius and diffuseness of the neutron distribution are found to be c(n)=6.70±0.03(stat.) fm and a(n)=0.55±0.01(stat.)(-0.03)(+0.02)(sys.) fm, respectively, corresponding to a neutron skin thickness Δr(np)=0.15±0.03(stat.)(-0.03)(+0.01)(sys.) fm. The results give the first successful extraction of a neutron skin thickness with an electromagnetic probe and indicate that the skin of (208)Pb has a halo character. The measurement provides valuable new constraints on both the structure of nuclei and the equation of state for neutron-rich matter.
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Affiliation(s)
- C M Tarbert
- 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
- Institut für Kernphysik, University of Mainz, Germany
| | - J Ahrens
- Institut für Kernphysik, University of Mainz, Germany
| | - J R M Annand
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - H J Arends
- Institut für Kernphysik, University of Mainz, Germany
| | - R Beck
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, Germany
| | - V Bekrenev
- Petersburg Nuclear Physics Institute, Gatchina, Russia
| | - B Boillat
- Institut für Physik, University of Basel, Basel, Switzerland
| | | | - D Branford
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - W J Briscoe
- Center for Nuclear Studies, The George Washington University, Washington, D.C. 20052, USA
| | - J Brudvik
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | | | - R Codling
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - E J Downie
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - K Foehl
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - P Grabmayr
- Physikalisches Institut Universität Tübingen, Tübingen, Germany
| | - R Gregor
- II. Physikalisches Institut, University of Giessen, Germany
| | - E Heid
- Institut für Kernphysik, University of Mainz, Germany
| | - D Hornidge
- Mount Allison University, Sackville, New Brunswick E4L 1E6, Canada
| | - O Jahn
- Institut für Kernphysik, University of Mainz, Germany
| | | | - A Knezevic
- Rudjer Boskovic Institute, Zagreb, Croatia
| | | | - M Korolija
- Rudjer Boskovic Institute, Zagreb, Croatia
| | - M Kotulla
- Institut für Physik, University of Basel, Basel, Switzerland
| | - D Krambrich
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, Germany
| | - B Krusche
- Institut für Physik, University of Basel, Basel, Switzerland
| | - M Lang
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, Germany
| | - V Lisin
- Institute for Nuclear Research, Moscow, Russia
| | - K Livingston
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - S Lugert
- II. Physikalisches Institut, University of Giessen, Germany
| | - I J D MacGregor
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - D M Manley
- Kent State University, Kent, Ohio 44240, USA
| | - M Martinez
- Institut für Kernphysik, University of Mainz, Germany
| | - J C McGeorge
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | | | - V Metag
- II. Physikalisches Institut, University of Giessen, Germany
| | - B M K Nefkens
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | - A Nikolaev
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, Germany
| | - R Novotny
- II. Physikalisches Institut, University of Giessen, Germany
| | - R O Owens
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | | | - A Polonski
- Institute for Nuclear Research, Moscow, Russia
| | - S N Prakhov
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | - J W Price
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | - G Rosner
- SUPA, Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - M Rost
- Institut für Kernphysik, University of Mainz, Germany
| | | | - S Schadmand
- II. Physikalisches Institut, University of Giessen, Germany
| | - S Schumann
- Institut für Kernphysik, University of Mainz, Germany and Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, Germany
| | - D Sober
- The Catholic University of America, Washington, D.C. 20064, USA
| | - A Starostin
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | - I Supek
- Rudjer Boskovic Institute, Zagreb, Croatia
| | - 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 Bonn, Germany
| | - Th Walcher
- Institut für Kernphysik, University of Mainz, Germany
| | - L Zana
- SUPA, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - F Zehr
- Institut für Physik, University of Basel, Basel, Switzerland
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