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Jermann N, Krusche B, Metag V, Afzal F, Badea M, Beck R, Bielefeldt P, Bieling J, Biroth M, Blanke E, Borisov N, Bornstein M, Brinkmann KT, Ciupka S, Crede V, Dolzhikov A, Drexler P, Dutz H, Elsner D, Fedorov A, Frommberger F, Gardner S, Ghosal D, Goertz S, Gorodnov I, Grüner M, Hammann C, Hartmann J, Hillert W, Hoffmeister P, Honisch C, Jude TC, Kalischewski F, Ketzer B, Klassen P, Klein F, Klempt E, Knaust J, Kolanus N, Kreit J, Krönert P, Lang M, Lazarev AB, Livingston K, Lutterer S, Mahlberg P, Meier C, Meyer W, Mitlasoczki B, Müllers J, Nanova M, Neganov A, Nikonov K, Noël JF, Ostrick M, Ottnad J, Otto B, Penman G, Poller T, Proft D, Reicherz G, Reinartz N, Richter L, Runkel S, Salisbury B, Sarantsev AV, Schaab D, Schmidt C, Schmieden H, Schultes J, Seifen T, Spieker K, Stausberg N, Steinacher M, Taubert F, Thiel A, Thoma U, Thomas A, Urban M, Urff G, Usov Y, van Pee H, Wang YC, Wendel C, Wiedner U, Wunderlich Y. Measurement of polarization observables T, P, and H in π0 and η photoproduction off quasi-free nucleons. Eur Phys J A Hadron Nucl 2023; 59:232. [PMID: 37860634 PMCID: PMC10582157 DOI: 10.1140/epja/s10050-023-01134-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/21/2023] [Indexed: 10/21/2023]
Abstract
The target asymmetry T, recoil asymmetry P, and beam-target double polarization observable H were determined in exclusive π 0 and η photoproduction off quasi-free protons and, for the first time, off quasi-free neutrons. The experiment was performed at the electron stretcher accelerator ELSA in Bonn, Germany, with the Crystal Barrel/TAPS detector setup, using a linearly polarized photon beam and a transversely polarized deuterated butanol target. Effects from the Fermi motion of the nucleons within deuterium were removed by a full kinematic reconstruction of the final state invariant mass. A comparison of the data obtained on the proton and on the neutron provides new insight into the isospin structure of the electromagnetic excitation of the nucleon. Earlier measurements of polarization observables in the γ p → π 0 p and γ p → η p reactions are confirmed. The data obtained on the neutron are of particular relevance for clarifying the origin of the narrow structure in the η n system at W = 1.68 GeV . A comparison with recent partial wave analyses favors the interpretation of this structure as arising from interference of the S 11 ( 1535 ) and S 11 ( 1650 ) resonances within the S 11 -partial wave.
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Affiliation(s)
- N. Jermann
- Department of Physics, University of Basel, Basel, Switzerland
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - B. Krusche
- Department of Physics, University of Basel, Basel, Switzerland
| | - V. Metag
- II. Physikalisches Institut, University of Giessen, Giessen, Germany
| | - F. Afzal
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - M. Badea
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - R. Beck
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - P. Bielefeldt
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - J. Bieling
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - M. Biroth
- Institut für Kernphysik, University of Mainz, Mainz, Germany
| | - E. Blanke
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - N. Borisov
- Joint Institute for Nuclear Research, Dubna, Russia
| | - M. Bornstein
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - K.-T. Brinkmann
- II. Physikalisches Institut, University of Giessen, Giessen, Germany
| | - S. Ciupka
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - V. Crede
- Department of Physics, Florida State University, Tallahassee, USA
| | - A. Dolzhikov
- Joint Institute for Nuclear Research, Dubna, Russia
| | - P. Drexler
- Institut für Kernphysik, University of Mainz, Mainz, Germany
| | - H. Dutz
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - D. Elsner
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - A. Fedorov
- Joint Institute for Nuclear Research, Dubna, Russia
| | - F. Frommberger
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - S. Gardner
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, UK
| | - D. Ghosal
- Department of Physics, University of Basel, Basel, Switzerland
- Present Address: resent address: University of Liverpool, Liverpool, UK
| | - S. Goertz
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - I. Gorodnov
- Joint Institute for Nuclear Research, Dubna, Russia
| | - M. Grüner
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - C. Hammann
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - J. Hartmann
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - W. Hillert
- Physikalisches Institut, University of Bonn, Bonn, Germany
- Present Address: resent address: University of Hamburg, Hamburg, Germany
| | - P. Hoffmeister
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - C. Honisch
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - T. C. Jude
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - F. Kalischewski
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - B. Ketzer
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - P. Klassen
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - F. Klein
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - E. Klempt
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - J. Knaust
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - N. Kolanus
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - J. Kreit
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - P. Krönert
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - M. Lang
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | | | - K. Livingston
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, UK
| | - S. Lutterer
- Department of Physics, University of Basel, Basel, Switzerland
- Present Address: resent address: Ruhr University Bochum, Bochum, Germany
| | - P. Mahlberg
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - C. Meier
- Department of Physics, University of Basel, Basel, Switzerland
| | - W. Meyer
- Institut für Experimentalphysik I, Ruhr University Bochum, Bochum, Germany
| | - B. Mitlasoczki
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - J. Müllers
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - M. Nanova
- II. Physikalisches Institut, University of Giessen, Giessen, Germany
| | - A. Neganov
- Joint Institute for Nuclear Research, Dubna, Russia
| | - K. Nikonov
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - J. F. Noël
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - M. Ostrick
- Institut für Kernphysik, University of Mainz, Mainz, Germany
| | - J. Ottnad
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - B. Otto
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - G. Penman
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, UK
| | - T. Poller
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - D. Proft
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - G. Reicherz
- Institut für Experimentalphysik I, Ruhr University Bochum, Bochum, Germany
| | - N. Reinartz
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - L. Richter
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - S. Runkel
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - B. Salisbury
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - A. V. Sarantsev
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - D. Schaab
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - C. Schmidt
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - H. Schmieden
- Physikalisches Institut, University of Bonn, Bonn, Germany
| | - J. Schultes
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - T. Seifen
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - K. Spieker
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - N. Stausberg
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - M. Steinacher
- Department of Physics, University of Basel, Basel, Switzerland
| | - F. Taubert
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - A. Thiel
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - U. Thoma
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - A. Thomas
- Institut für Kernphysik, University of Mainz, Mainz, Germany
| | - M. Urban
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - G. Urff
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - Y. Usov
- Joint Institute for Nuclear Research, Dubna, Russia
| | - H. van Pee
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - Y. C. Wang
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - C. Wendel
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - U. Wiedner
- Institut für Experimentalphysik I, Ruhr University Bochum, Bochum, Germany
| | - Y. Wunderlich
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
| | - CBELSA/TAPS Collaboration
- Department of Physics, University of Basel, Basel, Switzerland
- Helmholtz-Institut für Strahlen-und Kernphysik, University of Bonn, Bonn, Germany
- II. Physikalisches Institut, University of Giessen, Giessen, Germany
- Institut für Kernphysik, University of Mainz, Mainz, Germany
- Joint Institute for Nuclear Research, Dubna, Russia
- Department of Physics, Florida State University, Tallahassee, USA
- Physikalisches Institut, University of Bonn, Bonn, Germany
- SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, UK
- Institut für Experimentalphysik I, Ruhr University Bochum, Bochum, Germany
- Present Address: resent address: University of Liverpool, Liverpool, UK
- Present Address: resent address: University of Hamburg, Hamburg, Germany
- Present Address: resent address: Ruhr University Bochum, Bochum, Germany
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Adolph C, Akhunzyanov R, Alexeev MG, Alexeev GD, Amoroso A, Andrieux V, Anosov V, Austregesilo A, Badełek B, Balestra F, Barth J, Baum G, Beck R, Bedfer Y, Berlin A, Bernhard J, Bicker K, Bieling J, Birsa R, Bisplinghoff J, Bodlak M, Boer M, Bordalo P, Bradamante F, Braun C, Bressan A, Büchele M, Burtin E, Capozza L, Chiosso M, Chung SU, Cicuttin A, Colantoni M, Crespo ML, Curiel Q, Dalla Torre S, Dasgupta SS, Dasgupta S, Denisov OY, Dinkelbach AM, Donskov SV, Doshita N, Duic V, Dünnweber W, Dziewiecki M, Efremov A, Elia C, Eversheim PD, Eyrich W, Faessler M, Ferrero A, Filin A, Finger M, Finger M, Fischer H, Franco C, du Fresne von Hohenesche N, Friedrich JM, Frolov V, Gautheron F, Gavrichtchouk OP, Gerassimov S, Geyer R, Gnesi I, Gobbo B, Goertz S, Gorzellik M, Grabmüller S, Grasso A, Grube B, Grussenmeyer T, Guskov A, Guthörl T, Haas F, von Harrach D, Hahne D, Hashimoto R, Heinsius FH, Herrmann F, Hinterberger F, Höppner C, Horikawa N, d'Hose N, Huber S, Ishimoto S, Ivanov A, Ivanshin Y, Iwata T, Jahn R, Jary V, Jasinski P, Jörg P, Joosten R, Kabuss E, Ketzer B, Khaustov GV, Khokhlov YA, Kisselev Y, Klein F, Klimaszewski K, Koivuniemi JH, Kolosov VN, Kondo K, Königsmann K, Konorov I, Konstantinov VF, Kotzinian AM, Kouznetsov O, Krämer M, Kroumchtein ZV, Kuchinski N, Kuhn R, Kunne F, Kurek K, Kurjata RP, Lednev AA, Lehmann A, Levillain M, Levorato S, Lichtenstadt J, Maggiora A, Magnon A, Makke N, Mallot GK, Marchand C, Martin A, Marzec J, Matousek J, Matsuda H, Matsuda T, Meshcheryakov G, Meyer W, Michigami T, Mikhailov YV, Miyachi Y, Moinester MA, Nagaytsev A, Nagel T, Nerling F, Neubert S, Neyret D, Nikolaenko VI, Novy J, Nowak WD, Nunes AS, Olshevsky AG, Orlov I, Ostrick M, Panknin R, Panzieri D, Parsamyan B, Paul S, Peshekhonov D, Platchkov S, Pochodzalla J, Polyakov VA, Pretz J, Quaresma M, Quintans C, Ramos S, Regali C, Reicherz G, Rocco E, Rossiyskaya NS, Ryabchikov DI, Rychter A, Samoylenko VD, Sandacz A, Sarkar S, Savin IA, Sbrizzai G, Schiavon P, Schill C, Schlüter T, Schmidt K, Schmieden H, Schönning K, Schopferer S, Schott M, Shevchenko OY, Silva L, Sinha L, Sirtl S, Slunecka M, Sosio S, Sozzi F, Srnka A, Steiger L, Stolarski M, Sulc M, Sulej R, Suzuki H, Szabelski A, Szameitat T, Sznajder P, Takekawa S, ter Wolbeek J, Tessaro S, Tessarotto F, Thibaud F, Uhl S, Uman I, Virius M, Wang L, Weisrock T, Wilfert M, Windmolders R, Wollny H, Zaremba K, Zavertyaev M, Zemlyanichkina E, Ziembicki M, Zink A. Measurement of the charged-pion polarizability. Phys Rev Lett 2015; 114:062002. [PMID: 25723208 DOI: 10.1103/physrevlett.114.062002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Indexed: 06/04/2023]
Abstract
The COMPASS collaboration at CERN has investigated pion Compton scattering, π(-)γ→π(-)γ, at center-of-mass energy below 3.5 pion masses. The process is embedded in the reaction π(-)Ni→π(-)γNi, which is initiated by 190 GeV pions impinging on a nickel target. The exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, Q(2)<0.0015 (GeV/c)(2). From a sample of 63,000 events, the pion electric polarizability is determined to be α(π)=(2.0±0.6(stat)±0.7(syst))×10(-4) fm(3) under the assumption α(π)=-β(π), which relates the electric and magnetic dipole polarizabilities. It is the most precise measurement of this fundamental low-energy parameter of strong interaction that has been addressed since long by various methods with conflicting outcomes. While this result is in tension with previous dedicated measurements, it is found in agreement with the expectation from chiral perturbation theory. An additional measurement replacing pions by muons, for which the cross-section behavior is unambiguously known, was performed for an independent estimate of the systematic uncertainty.
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Affiliation(s)
- C Adolph
- Universität Erlangen-Nürnberg, Physikalisches Institut, 91054 Erlangen, Germany
| | - R Akhunzyanov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - M G Alexeev
- University of Turin, Department of Physics, 10125 Turin, Italy
| | - G D Alexeev
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - A Amoroso
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - V Andrieux
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - V Anosov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - A Austregesilo
- CERN, 1211 Geneva 23, Switzerland and Technische Universität München, Physik Department, 85748 Garching, Germany
| | - B Badełek
- University of Warsaw, Faculty of Physics, 00-681 Warsaw, Poland
| | - F Balestra
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - J Barth
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - G Baum
- Universität Bielefeld, Fakultät für Physik, 33501 Bielefeld, Germany
| | - R Beck
- Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, 53115 Bonn, Germany
| | - Y Bedfer
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - A Berlin
- Universität Bochum, Institut für Experimentalphysik, 44780 Bochum, Germany
| | - J Bernhard
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - K Bicker
- CERN, 1211 Geneva 23, Switzerland and Technische Universität München, Physik Department, 85748 Garching, Germany
| | - J Bieling
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - R Birsa
- Trieste Section of INFN, 34127 Trieste, Italy
| | - J Bisplinghoff
- Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, 53115 Bonn, Germany
| | - M Bodlak
- Charles University in Prague, Faculty of Mathematics and Physics, 18000 Prague, Czech Republic
| | - M Boer
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | | | - F Bradamante
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | - C Braun
- Universität Erlangen-Nürnberg, Physikalisches Institut, 91054 Erlangen, Germany
| | - A Bressan
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | - M Büchele
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - E Burtin
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - L Capozza
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - M Chiosso
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - S U Chung
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - A Cicuttin
- Trieste Section of INFN, 34127 Trieste, Italy and Abdus Salam ICTP, 34151 Trieste, Italy
| | | | - M L Crespo
- Trieste Section of INFN, 34127 Trieste, Italy and Abdus Salam ICTP, 34151 Trieste, Italy
| | - Q Curiel
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | | | - S S Dasgupta
- Matrivani Institute of Experimental Research & Education, Calcutta 700 030, India
| | - S Dasgupta
- Trieste Section of INFN, 34127 Trieste, Italy
| | | | - A M Dinkelbach
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - S V Donskov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - N Doshita
- Yamagata University, Yamagata, 992-8510 Japan
| | - V Duic
- University of Trieste, Department of Physics, 34127 Trieste, Italy
| | - W Dünnweber
- Ludwig-Maximilians-Universität München, Department für Physik, 80799 Munich, Germany
| | - M Dziewiecki
- Warsaw University of Technology, Institute of Radioelectronics, 00-665 Warsaw, Poland
| | - A Efremov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - C Elia
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | - P D Eversheim
- Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, 53115 Bonn, Germany
| | - W Eyrich
- Universität Erlangen-Nürnberg, Physikalisches Institut, 91054 Erlangen, Germany
| | - M Faessler
- Ludwig-Maximilians-Universität München, Department für Physik, 80799 Munich, Germany
| | - A Ferrero
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - A Filin
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - M Finger
- Charles University in Prague, Faculty of Mathematics and Physics, 18000 Prague, Czech Republic
| | - M Finger
- Charles University in Prague, Faculty of Mathematics and Physics, 18000 Prague, Czech Republic
| | - H Fischer
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | | | | | - J M Friedrich
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - V Frolov
- CERN, 1211 Geneva 23, Switzerland
| | - F Gautheron
- Universität Bochum, Institut für Experimentalphysik, 44780 Bochum, Germany
| | - O P Gavrichtchouk
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - S Gerassimov
- Lebedev Physical Institute, 119991 Moscow, Russia and Technische Universität München, Physik Department, 85748 Garching, Germany
| | - R Geyer
- Ludwig-Maximilians-Universität München, Department für Physik, 80799 Munich, Germany
| | - I Gnesi
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - B Gobbo
- Trieste Section of INFN, 34127 Trieste, Italy
| | - S Goertz
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - M Gorzellik
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - S Grabmüller
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - A Grasso
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - B Grube
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - T Grussenmeyer
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - A Guskov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - T Guthörl
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - F Haas
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - D von Harrach
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - D Hahne
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - R Hashimoto
- Yamagata University, Yamagata, 992-8510 Japan
| | - F H Heinsius
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - F Herrmann
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - F Hinterberger
- Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, 53115 Bonn, Germany
| | - Ch Höppner
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | | | - N d'Hose
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - S Huber
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - S Ishimoto
- Yamagata University, Yamagata, 992-8510 Japan
| | - A Ivanov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - Yu Ivanshin
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - T Iwata
- Yamagata University, Yamagata, 992-8510 Japan
| | - R Jahn
- Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, 53115 Bonn, Germany
| | - V Jary
- Czech Technical University in Prague, 16636 Prague, Czech Republic
| | - P Jasinski
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - P Jörg
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - R Joosten
- Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, 53115 Bonn, Germany
| | - E Kabuss
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - B Ketzer
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - G V Khaustov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - Yu A Khokhlov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - Yu Kisselev
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - F Klein
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - K Klimaszewski
- National Centre for Nuclear Research, 00-681 Warsaw, Poland
| | - J H Koivuniemi
- Universität Bochum, Institut für Experimentalphysik, 44780 Bochum, Germany
| | - V N Kolosov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - K Kondo
- Yamagata University, Yamagata, 992-8510 Japan
| | - K Königsmann
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - I Konorov
- Lebedev Physical Institute, 119991 Moscow, Russia and Technische Universität München, Physik Department, 85748 Garching, Germany
| | - V F Konstantinov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - A M Kotzinian
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - O Kouznetsov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - M Krämer
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - Z V Kroumchtein
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - N Kuchinski
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - R Kuhn
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - F Kunne
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - K Kurek
- National Centre for Nuclear Research, 00-681 Warsaw, Poland
| | - R P Kurjata
- Warsaw University of Technology, Institute of Radioelectronics, 00-665 Warsaw, Poland
| | - A A Lednev
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - A Lehmann
- Universität Erlangen-Nürnberg, Physikalisches Institut, 91054 Erlangen, Germany
| | - M Levillain
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - S Levorato
- Trieste Section of INFN, 34127 Trieste, Italy
| | - J Lichtenstadt
- Tel Aviv University, School of Physics and Astronomy, 69978 Tel Aviv, Israel
| | - A Maggiora
- Torino Section of INFN, 10125 Turin, Italy
| | - A Magnon
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - N Makke
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | | | - C Marchand
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - A Martin
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | - J Marzec
- Warsaw University of Technology, Institute of Radioelectronics, 00-665 Warsaw, Poland
| | - J Matousek
- Charles University in Prague, Faculty of Mathematics and Physics, 18000 Prague, Czech Republic
| | - H Matsuda
- Yamagata University, Yamagata, 992-8510 Japan
| | - T Matsuda
- University of Miyazaki, Miyazaki 889-2192, Japan
| | - G Meshcheryakov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - W Meyer
- Universität Bochum, Institut für Experimentalphysik, 44780 Bochum, Germany
| | - T Michigami
- Yamagata University, Yamagata, 992-8510 Japan
| | - Yu V Mikhailov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - Y Miyachi
- Yamagata University, Yamagata, 992-8510 Japan
| | - M A Moinester
- Tel Aviv University, School of Physics and Astronomy, 69978 Tel Aviv, Israel
| | - A Nagaytsev
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - T Nagel
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - F Nerling
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - S Neubert
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - D Neyret
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - V I Nikolaenko
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - J Novy
- Czech Technical University in Prague, 16636 Prague, Czech Republic
| | - W-D Nowak
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | | | - A G Olshevsky
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - I Orlov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - M Ostrick
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - R Panknin
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - D Panzieri
- University of Eastern Piedmont, 15100 Alessandria, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - B Parsamyan
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - S Paul
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - D Peshekhonov
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - S Platchkov
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - J Pochodzalla
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - V A Polyakov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - J Pretz
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | | | | | - S Ramos
- LIP, 1000-149 Lisbon, Portugal
| | - C Regali
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - G Reicherz
- Universität Bochum, Institut für Experimentalphysik, 44780 Bochum, Germany
| | - E Rocco
- CERN, 1211 Geneva 23, Switzerland
| | - N S Rossiyskaya
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - D I Ryabchikov
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - A Rychter
- Warsaw University of Technology, Institute of Radioelectronics, 00-665 Warsaw, Poland
| | - V D Samoylenko
- State Scientific Center Institute for High Energy Physics of National Research Center "Kurchatov Institute," 142281 Protvino, Russia
| | - A Sandacz
- National Centre for Nuclear Research, 00-681 Warsaw, Poland
| | - S Sarkar
- Matrivani Institute of Experimental Research & Education, Calcutta 700 030, India
| | - I A Savin
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - G Sbrizzai
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | - P Schiavon
- University of Trieste, Department of Physics, 34127 Trieste, Italy and Trieste Section of INFN, 34127 Trieste, Italy
| | - C Schill
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - T Schlüter
- Ludwig-Maximilians-Universität München, Department für Physik, 80799 Munich, Germany
| | - K Schmidt
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - H Schmieden
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | | | - S Schopferer
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - M Schott
- CERN, 1211 Geneva 23, Switzerland
| | - O Yu Shevchenko
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - L Silva
- LIP, 1000-149 Lisbon, Portugal
| | - L Sinha
- Matrivani Institute of Experimental Research & Education, Calcutta 700 030, India
| | - S Sirtl
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - M Slunecka
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - S Sosio
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - F Sozzi
- Trieste Section of INFN, 34127 Trieste, Italy
| | - A Srnka
- Institute of Scientific Instruments, AS CR, 61264 Brno, Czech Republic
| | - L Steiger
- Trieste Section of INFN, 34127 Trieste, Italy
| | | | - M Sulc
- Technical University in Liberec, 46117 Liberec, Czech Republic
| | - R Sulej
- National Centre for Nuclear Research, 00-681 Warsaw, Poland
| | - H Suzuki
- Yamagata University, Yamagata, 992-8510 Japan
| | - A Szabelski
- National Centre for Nuclear Research, 00-681 Warsaw, Poland
| | - T Szameitat
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - P Sznajder
- National Centre for Nuclear Research, 00-681 Warsaw, Poland
| | - S Takekawa
- University of Turin, Department of Physics, 10125 Turin, Italy and Torino Section of INFN, 10125 Turin, Italy
| | - J ter Wolbeek
- Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
| | - S Tessaro
- Trieste Section of INFN, 34127 Trieste, Italy
| | | | - F Thibaud
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - S Uhl
- Technische Universität München, Physik Department, 85748 Garching, Germany
| | - I Uman
- Ludwig-Maximilians-Universität München, Department für Physik, 80799 Munich, Germany
| | - M Virius
- Czech Technical University in Prague, 16636 Prague, Czech Republic
| | - L Wang
- Universität Bochum, Institut für Experimentalphysik, 44780 Bochum, Germany
| | - T Weisrock
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - M Wilfert
- Universität Mainz, Institut für Kernphysik, 55099 Mainz, Germany
| | - R Windmolders
- Universität Bonn, Physikalisches Institut, 53115 Bonn, Germany
| | - H Wollny
- CEA IRFU/SPhN Saclay, 91191 Gif-sur-Yvette, France
| | - K Zaremba
- Warsaw University of Technology, Institute of Radioelectronics, 00-665 Warsaw, Poland
| | - M Zavertyaev
- Lebedev Physical Institute, 119991 Moscow, Russia
| | - E Zemlyanichkina
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
| | - M Ziembicki
- Warsaw University of Technology, Institute of Radioelectronics, 00-665 Warsaw, Poland
| | - A Zink
- Universität Erlangen-Nürnberg, Physikalisches Institut, 91054 Erlangen, Germany
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Adolph C, Alekseev MG, Alexakhin VY, Alexandrov Y, Alexeev GD, Amoroso A, Antonov AA, Austregesilo A, Badełek B, Balestra F, Barth J, Baum G, Bedfer Y, Bernhard J, Bertini R, Bettinelli M, Bicker KA, Birsa R, Bisplinghoff J, Bordalo P, Bradamante F, Braun C, Bravar A, Bressan A, Burtin E, Chaberny D, Chiosso M, Chung SU, Cicuttin A, Crespo ML, Dalla Torre S, Das S, Dasgupta SS, Denisov OY, Dhara L, Donskov SV, Doshita N, Duic V, Dünnweber W, Dziewiecki M, Efremov A, Elia C, Eversheim PD, Eyrich W, Faessler M, Ferrero A, Filin A, Finger M, Finger M, Fischer H, Franco C, du Fresne von Hohenesche N, Friedrich JM, Garfagnini R, Gautheron F, Gavrichtchouk OP, Gazda R, Gerassimov S, Geyer R, Giorgi M, Gnesi I, Gobbo B, Goertz S, Grabmüller S, Grasso A, Grube B, Gushterski R, Guskov A, Haas F, von Harrach D, Hasegawa T, Heinsius FH, Herrmann F, Hess C, Hinterberger F, Horikawa N, Höppner C, d'Hose N, Huber S, Ishimoto S, Ivanov O, Ivanshin Y, Iwata T, Jahn R, Jasinski P, Jegou G, Joosten R, Kabuss E, Kang D, Ketzer B, Khaustov GV, Khokhlov YA, Kisselev Y, Klein F, Klimaszewski K, Koblitz S, Koivuniemi JH, Kolosov VN, Kondo K, Königsmann K, Konorov I, Konstantinov VF, Korzenev A, Kotzinian AM, Kouznetsov O, Krämer M, Kroumchtein ZV, Kunne F, Kurek K, Lauser L, Lednev AA, Lehmann A, Levorato S, Lichtenstadt J, Maggiora A, Magnon A, Makke N, Mallot GK, Mann A, Marchand C, Martin A, Marzec J, Massmann F, Matsuda T, Meyer W, Michigami T, Mikhailov YV, Moinester MA, Morreale A, Mutter A, Nagaytsev A, Nagel T, Nerling F, Neubert S, Neyret D, Nikolaenko VI, Nowak WD, Nunes AS, Olshevsky AG, Ostrick M, Padee A, Panknin R, Panzieri D, Parsamyan B, Paul S, Perevalova E, Pesaro G, Peshekhonov DV, Piragino G, Platchkov S, Pochodzalla J, Polak J, Polyakov VA, Pontecorvo G, Pretz J, Quintans C, Rajotte JF, Ramos S, Rapatsky V, Reicherz G, Richter A, Rocco E, Rondio E, Rossiyskaya NS, Ryabchikov DI, Samoylenko VD, Sandacz A, Sapozhnikov MG, Sarkar S, Savin IA, Sbrizzai G, Schiavon P, Schill C, Schlüter T, Schmitt L, Schönning K, Schopferer S, Schröder W, Shevchenko OY, Siebert HW, Silva L, Sinha L, Sissakian AN, Slunecka M, Smirnov GI, Sosio S, Sozzi F, Srnka A, Stolarski M, Sulc M, Sulej R, Sznajder P, Takekawa S, Ter Wolbeek J, Tessaro S, Tessarotto F, Teufel A, Tkatchev LG, Uhl S, Uman I, Vandenbroucke M, Virius M, Vlassov NV, Windmolders R, Wiślicki W, Wollny H, Zaremba K, Zavertyaev M, Zemlyanichkina E, Ziembicki M, Zhuravlev N, Zvyagin A. First measurement of chiral dynamics in π- γ → π- π- π+. Phys Rev Lett 2012; 108:192001. [PMID: 23003028 DOI: 10.1103/physrevlett.108.192001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Indexed: 06/01/2023]
Abstract
The COMPASS Collaboration at CERN has investigated the π- γ → π- π- π+ reaction at center-of-momentum energy below five pion masses, sqrt[s]<5m(π), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t'<0.001 GeV2/c2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3π-invariant mass m(3π)=sqrt[s] were extracted. The absolute cross section was determined in seven bins of sqrt[s] with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.
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Affiliation(s)
- C Adolph
- Universität Erlangen-Nürnberg, Physikalisches Institut, 91054 Erlangen, Germany
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Alekseev MG, Alexakhin VY, Alexandrov Y, Alexeev GD, Amoroso A, Austregesilo A, Badełek B, Balestra F, Ball J, Barth J, Baum G, Bedfer Y, Bernhard J, Bertini R, Bettinelli M, Birsa R, Bisplinghoff J, Bordalo P, Bradamante F, Bravar A, Bressan A, Brona G, Burtin E, Bussa MP, Chapiro A, Chiosso M, Chung SU, Cicuttin A, Colantoni M, Crespo ML, Dalla Torre S, Dafni T, Das S, Dasgupta SS, Denisov OY, Dhara L, Diaz V, Dinkelbach AM, Donskov SV, Doshita N, Duic V, Dünnweber W, Efremov A, El Alaoui A, Eversheim PD, Eyrich W, Faessler M, Ferrero A, Finger M, Finger M, Fischer H, Franco C, Friedrich JM, Garfagnini R, Gautheron F, Gavrichtchouk OP, Gazda R, Gerassimov S, Geyer R, Giorgi M, Gobbo B, Goertz S, Grabmüller S, Grajek OA, Grasso A, Grube B, Gushterski R, Guskov A, Haas F, von Harrach D, Hasegawa T, Heckmann J, Heinsius FH, Hermann R, Herrmann F, Hess C, Hinterberger F, Horikawa N, Höppner C, d'Hose N, Ilgner C, Ishimoto S, Ivanov O, Ivanshin Y, Iwata T, Jahn R, Jasinski P, Jegou G, Joosten R, Kabuss E, Kang D, Ketzer B, Khaustov GV, Khokhlov YA, Kisselev Y, Klein F, Klimaszewski K, Koblitz S, Koivuniemi JH, Kolosov VN, Komissarov EV, Kondo K, Königsmann K, Konopka R, Konorov I, Konstantinov VF, Korzenev A, Kotzinian AM, Kouznetsov O, Kowalik K, Krämer M, Kral A, Kroumchtein ZV, Kuhn R, Kunne F, Kurek K, Lauser L, Le Goff JM, Lednev AA, Lehmann A, Levorato S, Lichtenstadt J, Liska T, Maggiora A, Maggiora M, Magnon A, Mallot GK, Mann A, Marchand C, Marroncle J, Martin A, Marzec J, Massmann F, Matsuda T, Maximov AN, Meyer W, Michigami T, Mikhailov YV, Moinester MA, Mutter A, Nagaytsev A, Nagel T, Nassalski J, Negrini T, Nerling F, Neubert S, Neyret D, Nikolaenko VI, Olshevsky AG, Ostrick M, Padee A, Panknin R, Panzieri D, Parsamyan B, Paul S, Pawlukiewicz-Kaminska B, Perevalova E, Pesaro G, Peshekhonov DV, Piragino G, Platchkov S, Pochodzalla J, Polak J, Polyakov VA, Pontecorvo G, Pretz J, Quintans C, Rajotte JF, Ramos S, Rapatsky V, Reicherz G, Reggiani D, Richter A, Robinet F, Rocco E, Rondio E, Ryabchikov DI, Samoylenko VD, Sandacz A, Santos H, Sapozhnikov MG, Sarkar S, Savin IA, Sbrizzai G, Schiavon P, Schill C, Schlüter T, Schmitt L, Schopferer S, Schröder W, Shevchenko OY, Siebert HW, Silva L, Sinha L, Sissakian AN, Slunecka M, Smirnov GI, Sosio S, Sozzi F, Srnka A, Stolarski M, Sulc M, Sulej R, Takekawa S, Tessaro S, Tessarotto F, Teufel A, Tkatchev LG, Uhl S, Uman I, Venugopal G, Virius M, Vlassov NV, Vossen A, Weitzel Q, Windmolders R, Wiślicki W, Wollny H, Zaremba K, Zavertyaev M, Zemlyanichkina E, Ziembicki M, Zhao J, Zhuravlev N, Zvyagin A. Observation of a J(PC)=1-+ exotic resonance in diffractive dissociation of 190 GeV/c π- into π- π- π+. Phys Rev Lett 2010; 104:241803. [PMID: 20867295 DOI: 10.1103/physrevlett.104.241803] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Indexed: 05/29/2023]
Abstract
The COMPASS experiment at the CERN SPS has studied the diffractive dissociation of negative pions into the π- π- π+ final state using a 190 GeV/c pion beam hitting a lead target. A partial wave analysis has been performed on a sample of 420,000 events taken at values of the squared 4-momentum transfer t' between 0.1 and 1 GeV2/c2. The well-known resonances a1(1260), a2(1320), and π2(1670) are clearly observed. In addition, the data show a significant natural-parity exchange production of a resonance with spin-exotic quantum numbers J(PC)=1-+ at 1.66 GeV/c2 decaying to ρπ. The resonant nature of this wave is evident from the mass-dependent phase differences to the J(PC)=2-+ and 1++ waves. From a mass-dependent fit a resonance mass of (1660±10(-64)(+0)) MeV/c2 and a width of (269±21(-64)(+42)) MeV/c2 are deduced, with an intensity of (1.7±0.2)% of the total intensity.
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Ahrens J, Altieri S, Annand JRM, Arends HJ, Beck R, Bradtke C, Braghieri A, d'Hose N, Dutz H, Goertz S, Grabmayr P, Hasegawa S, Heid E, Holvoet H, Van Hoorebeke L, Horikawa N, Iwata T, Jahn O, Jennewein P, Klein F, Kondratiev R, Lang M, Lannoy B, Lisin V, Martinez-Fabregate M, McGeorge JC, Meyer W, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Reicherz G, Rohlof C, Rosner G, Rost M, Rostomyan T, Ryckbosch D, Schumacher M, Seitz B, Tamas G, Thomas A, Van de Vyver R, Zapadtka F. Measurement of the Gerasimov-Drell-Hearn Integrand for 2H from 200 to 800 MeV. Phys Rev Lett 2006; 97:202303. [PMID: 17155680 DOI: 10.1103/physrevlett.97.202303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2006] [Indexed: 05/12/2023]
Abstract
A measurement of the helicity dependence of the total inclusive photoabsorption cross section on the deuteron was carried out at MAMI (Mainz) in the energy range 200<Egamma<800 MeV. The experiment used a 4pi detection system, a circularly polarized tagged photon beam and a frozen-spin target which provided longitudinally polarized deuterons. The contribution to the Gerasimov-Drell-Hearn sum rule for the deuteron determined from the data is 407+/-20(stat)+/-24(syst) mu b for 200<Egamma<800 MeV.
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Affiliation(s)
- J Ahrens
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
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Alexakhin VY, Alexandrov Y, Alexeev GD, Amoroso A, Badełek B, Balestra F, Ball J, Baum G, Bedfer Y, Berglund P, Bernet C, Bertini R, Birsa R, Bisplinghoff J, Bradamante F, Bravar A, Bressan A, Burtin E, Bussa MP, Cerini L, Chapiro A, Cicuttin A, Colantoni M, Colavita AA, Costa S, Crespo ML, d'Hose N, Dalla Torre S, Dasgupta SS, De Masi R, Dedek N, Denisov OY, Dhara L, Diaz Kavka V, Dolgopolov AV, Donskov SV, Dorofeev VA, Doshita N, Duic V, Dünnweber W, Efremov A, Ehlers J, Eversheim PD, Eyrich W, Fabro M, Faessler M, Fauland P, Ferrero A, Ferrero L, Finger M, Finger M, Fischer H, Franz J, Friedrich JM, Frolov V, Fuchs U, Garfagnini R, Gautheron F, Gavrichtchouk OP, Gerassimov S, Geyer R, Giorgi M, Gobbo B, Goertz S, Grajek OA, Grasso A, Grube B, Grünemaier A, Gustafsson K, Hannappel J, von Harrach D, Hasegawa T, Hedicke S, Heinsius FH, Hinterberger F, von Hodenberg M, Horikawa N, Horikawa S, Ijaduola RB, Ilgner C, Ishimoto S, Iwata T, Jahn R, Janata A, Joosten R, Jouravlev NI, Kabuss E, Kalinnikov V, Kang D, Karstens F, Kastaun W, Ketzer B, Khaustov GV, Khokhlov YA, Kisselev Y, Klein F, Koivuniemi JH, Kolosov VN, Komissarov EV, Kondo K, Königsmann K, Konoplyannikov AK, Konorov I, Konstantinov VF, Korentchenko AS, Korzenev A, Kotzinian AM, Koutchinski NA, Kowalik K, Kravchuk NP, Krivokhizhin GV, Kroumchtein ZV, Kuhn R, Kunne F, Kurek K, Lamanna M, Le Goff JM, Leberig M, Lichtenstadt J, Maggiora A, Maggiora M, Magnon A, Mallot GK, Manuilov IV, Marchand C, Marroncle J, Martin A, Marzec J, Matsuda T, Maximov AN, Medved KS, Meyer W, Mielech A, Mikhailov YV, Moinester MA, Nähle O, Nassalski J, Neyret DP, Nikolaenko VI, Nozdrin AA, Obraztsov VF, Olshevsky AG, Ostrick M, Padee A, Pagano P, Panebianco S, Panzieri D, Paul S, Pereira HD, Peshekhonov DV, Peshekhonov VD, Piragino G, Platchkov S, Platzer K, Pochodzalla J, Polyakov VA, Popov AA, Pretz J, Rebourgeard PC, Reicherz G, Reymann J, Rozhdestvensky AM, Rondio E, Sadovski AB, Saller E, Samoylenko VD, Sandacz A, Sans M, Sapozhnikov MG, Savin IA, Schiavon P, Schmidt T, Schmitt H, Schmitt L, Shishkin AA, Siebert H, Sinha L, Sissakian AN, Skachkova A, Slunecka M, Smirnov GI, Sugonyaev VP, Stinzing F, Sulej R, Takabayashi N, Tchalishev VV, Tessarotto F, Teufel A, Thers D, Tkatchev LG, Toeda T, Tretyak VI, Trousov S, Vlassov NV, Webb R, Weise E, Wiesmann M, Windmolders R, Wirth S, Wiślicki W, Zanetti AM, Zaremba K, Zhao J, Ziegler R, Zvyagin A. First measurement of the transverse spin asymmetries of the deuteron in semi-inclusive deep inelastic scattering. Phys Rev Lett 2005; 94:202002. [PMID: 16090237 DOI: 10.1103/physrevlett.94.202002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Indexed: 05/03/2023]
Abstract
First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.
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Affiliation(s)
- V Yu Alexakhin
- Joint Institute for Nuclear Research, 141980 Dubna, Moscow region, Russia
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7
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Dutz H, Helbing K, Krimmer J, Speckner T, Zeitler G, Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Beck R, Bock A, Bradtke C, Braghieri A, v Drachenfels W, Frommberger F, Godo M, Goertz S, Grabmayr P, Hasegawa S, Hansen K, Harmsen J, Heid E, Hillert W, Holvoet H, Horikawa N, Iwata T, Van Hoorebeke L, d'Hose N, Jennewein P, Kiel B, Klein F, Kondratiev R, Lang M, Lannoy B, Leukel R, Lisin V, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reicherz G, Rohlof C, Rostomyan T, Sauer M, Schoch B, Schumacher M, Tamas G, Thomas A, van de Vyver R, Weihofen W, Zapadtka F. Measurement of helicity-dependent photoabsorption cross sections on the neutron from 815 to 1825 MeV. Phys Rev Lett 2005; 94:162001. [PMID: 15904214 DOI: 10.1103/physrevlett.94.162001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Indexed: 05/02/2023]
Abstract
Helicity-dependent total photoabsorption cross sections on the deuteron have been measured for the first time at ELSA (Bonn) in the photon energy range from 815 to 1825 MeV. Circularly polarized tagged photons impinging on a longitudinally polarized LiD target have been used together with a highly efficient 4pi detector system. The data around 1 GeV are not compatible with predictions from existing multipole analyses. From the measured energy range an experimental contribution to the GDH integral on the neutron of [33.9 +/- 5.5(stat) +/- 4.5(syst)] microb is extracted.
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Affiliation(s)
- H Dutz
- Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany
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8
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Dutz H, Helbing K, Krimmer J, Speckner T, Zeitler G, Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Beck R, Bock A, Bradtke C, Braghieri A, v Drachenfels W, Frommberger F, Godo M, Goertz S, Grabmayr P, Hasegawa S, Hansen K, Harmsen J, Heid E, Hillert W, Holvoet H, Horikawa N, Iwata T, Hoorebeke LV, D'Hose N, Jennewein P, Kiel B, Klein F, Kondratiev R, Lang M, Lannoy B, Leukel R, Lisin V, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reicherz G, Rohlof C, Rostomyan T, Sauer M, Schoch B, Schumacher M, Tamas G, Thomas A, van de Vyver R, Weihofen W, Zapadtka F. Experimental check of the Gerasimov-Drell-Hearn sum rule for 1H. Phys Rev Lett 2004; 93:032003. [PMID: 15323817 DOI: 10.1103/physrevlett.93.032003] [Citation(s) in RCA: 5] [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: 02/21/2004] [Indexed: 05/24/2023]
Abstract
For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution to the GDH integral from 0.2-2.9 GeV yields [254+/-5(stat)+/-12(syst)] microb with negative contributions in the Regge regime at photon energies above 2.1 GeV. This trend supports the validity of the GDH sum rule.
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Affiliation(s)
- H Dutz
- Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany
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9
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Dutz H, Helbing K, Krimmer J, Speckner T, Zeitler G, Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Beck R, Bock A, Bradtke C, Braghieri A, v Drachenfels W, Frommberger F, Godo M, Goertz S, Grabmayr P, Hasegawa S, Hansen K, Harmsen J, Heid E, Hillert W, Holvoet H, Horikawa N, Iwata T, Van Hoorebeke L, d'Hose N, Jennewein P, Kiel B, Klein F, Kondratiev R, Lang M, Lannoy B, Leukel R, Lisin V, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reicherz G, Rohlof C, Rostomyan T, Sauer M, Schoch B, Schumacher M, Tamas G, Thomas A, van de Vyver R, Weihofen W, Zapadtka F. First Measurement of the Gerasimov-Drell-Hearn Sum Rule for 1H from 0.7 to 1.8 GeV at ELSA. Phys Rev Lett 2003; 91:192001. [PMID: 14611575 DOI: 10.1103/physrevlett.91.192001] [Citation(s) in RCA: 8] [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: 05/14/2003] [Indexed: 05/24/2023]
Abstract
To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] microb.
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Affiliation(s)
- H Dutz
- Physikalisches Institut, Universität Bonn, D-53115 Bonn, Germany
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10
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Bassalleck B, Berdoz A, Bradtke C, Bröders R, Bunker B, Dennert H, Dutz H, Eilerts S, Eyrich W, Fields D, Fischer H, Franklin G, Franz J, Gehring R, Geyer R, Goertz S, Harmsen J, Hauffe J, Heinsius FH, Hertzog D, Johansson T, Jones T, Khaustov P, Kilian K, Kingsberry P, Kriegler E, Lowe J, Meier A, Metzger A, Meyer CA, Meyer W, Moosburger M, Oelert W, Paschke KD, Plückthun M, Pomp S, Quinn B, Radtke E, Reicherz G, Röhrich K, Sachs K, Schmitt H, Schoch B, Sefzick T, Stinzing F, Stotzer R, Tayloe R, Wirth S. Measurement of spin-transfer observables in p p-->Lambda Lambda at 1.637 GeV/c. Phys Rev Lett 2002; 89:212302. [PMID: 12443404 DOI: 10.1103/physrevlett.89.212302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2002] [Indexed: 05/24/2023]
Abstract
Spin-transfer observables for p p-->Lambda Lambda have been measured using a transversely polarized frozen-spin target and a beam momentum of 1.637 GeV/c. Current models of the reaction near threshold are in good agreement with existing measurements performed with unpolarized particles in the initial state but produce conflicting predictions for the spin-transfer observables Dnn and Knn (the normal-to-normal depolarization and polarization transfer), which are measurable only with polarized target or beam. Measurements of Dnn and Knn presented here are found to be in disagreement with predictions from these models.
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Affiliation(s)
- B Bassalleck
- University of New Mexico, Albuquerque, New Mexico 87131, USA
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11
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Ahrens J, Altieri S, Annand JRM, Anton G, Arends HJ, Aulenbacher K, Beck R, Bradtke C, Braghieri A, Degrande N, D'Hose N, Drechsel D, Dutz H, Goertz S, Grabmayr P, Hansen K, Harmsen J, Von Harrach D, Hasegawa S, Hasegawa T, Heid E, Helbing K, Holvoet H, Van Hoorebeke L, Horikawa N, Iwata T, Jahn O, Jennewein P, Kageya T, Kamalov S, Kiel B, Klein F, Kondratiev R, Kossert K, Krimmer J, Lang M, Lannoy B, Leukel R, Lisin V, Matsuda T, McGeorge JC, Meier A, Menze D, Meyer W, Michel T, Naumann J, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E, Reichert E, Reicherz G, Rohlof C, Rosner G, Ryckbosch D, Sauer M, Schoch B, Schumacher M, Seitz B, Speckner T, Takabayashi N, Tamas G, Thomas A, Tiator L, Van Vyver R, Wakai A, Weihofen W, Wissmann F, Zapadtka F, Zeitler G. Helicity amplitudes A1/2 and A3/2 for the D13(1520) resonance obtained from the gamma-->p-->-->ppi(0) Reaction. Phys Rev Lett 2002; 88:232002. [PMID: 12059355 DOI: 10.1103/physrevlett.88.232002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2002] [Indexed: 05/23/2023]
Abstract
The helicity dependence of the gamma-->p-->-->ppi(0) reaction has been measured for the first time in the photon-energy range from 550 to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. These data are predominantly sensitive to the D13(1520) resonance and are used to determine its helicity amplitudes.
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Affiliation(s)
- J Ahrens
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany
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12
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Ahrens J, Altieri S, Annand JR, Anton G, Arends H, Aulenbacher K, Beck R, Bradtke C, Braghieri A, Degrande N, d'Hose N, Dutz H, Goertz S, Grabmayr P, Hansen K, Harmsen J, von Harrach D, Hasegawa S, Hasegawa T, Heid E, Helbing K, Holvoet H, Van Hoorebeke L, Horikawa N, Iwata T, Jennewein P, Kageya T, Kiel B, Klein F, Kondratiev R, Kossert K, Krimmer J, Lang M, Lannoy B, Leukel R, Lisin V, Matsuda T, McGeorge JC, Meier A, Menze D, Meyer W, Michel T, Naumann J, Owens RO, Panzeri A, Pedroni P, Pinelli T, Preobrajenski I, Radtke E. Helicity dependence of gammap --> Npi below 450 MeV and contribution to the Gerasimov-Drell-Hearn sum rule. Phys Rev Lett 2000; 84:5950-5954. [PMID: 10991096 DOI: 10.1103/physrevlett.84.5950] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2000] [Indexed: 05/23/2023]
Abstract
The helicity dependence of the single pion photoproduction on the proton has been measured in the energy range from 200 to 450 MeV for the first time. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a frozen-spin target. The data obtained provide new information for multipole analyses of pion photoproduction and determine the main contributions to the Gerasimov-Drell-Hearn sum rule and the forward spin polarizability gamma(0).
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Affiliation(s)
- J Ahrens
- Institut für Kernphysik, Universität Mainz, D-55099 Mainz, Germany.
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