Physics Letters B (Sep 2020)

Beam–target helicity asymmetry E in K+Σ− photoproduction on the neutron

  • N. Zachariou,
  • D.P. Watts,
  • J. Fleming,
  • A.V. Sarantsev,
  • V.A. Nikonov,
  • A. D'Angelo,
  • M. Bashkanov,
  • C. Hanretty,
  • T. Kageya,
  • F.J. Klein,
  • M. Lowry,
  • H. Lu,
  • A. Sandorfi,
  • X. Wei,
  • I. Zonta,
  • K.P. Adhikari,
  • S. Adhikari,
  • M.J. Amaryan,
  • G. Angelini,
  • G. Asryan,
  • H. Atac,
  • L. Barion,
  • C. Bass,
  • M. Battaglieri,
  • I. Bedlinskiy,
  • F. Benmokhtar,
  • A. Bianconi,
  • A.S. Biselli,
  • F. Bossù,
  • S. Boiarinov,
  • W.J. Briscoe,
  • W.K. Brooks,
  • D. Bulumulla,
  • V. Burkert,
  • D.S. Carman,
  • J.C. Carvajal,
  • A. Celentano,
  • G. Charles,
  • P. Chatagnon,
  • T. Chetry,
  • G. Ciullo,
  • P.L. Cole,
  • M. Contalbrigo,
  • N. Dashyan,
  • R. De Vita,
  • A. Deur,
  • S. Diehl,
  • C. Djalali,
  • R. Dupre,
  • H. Egiyan,
  • M. Ehrhart,
  • A. El Alaoui,
  • P. Eugenio,
  • S. Fegan,
  • R. Fersch,
  • A. Filippi,
  • G. Gavalian,
  • N. Gevorgyan,
  • Y. Ghandilyan,
  • G.P. Gilfoyle,
  • F.X. Girod,
  • W. Gohn,
  • E. Golovatch,
  • R.W. Gothe,
  • K.A. Griffioen,
  • M. Guidal,
  • K. Hafidi,
  • H. Hakobyan,
  • M. Hattawy,
  • D. Heddle,
  • K. Hicks,
  • D. Ho,
  • M. Holtrop,
  • Y. Ilieva,
  • D.G. Ireland,
  • B.S. Ishkhanov,
  • E.L. Isupov,
  • D. Jenkins,
  • H.S. Jo,
  • K. Joo,
  • S.J. Joosten,
  • D. Keller,
  • M. Khachatryan,
  • A. Khanal,
  • M. Khandaker,
  • C.W. Kim,
  • W. Kim,
  • V. Kubarovsky,
  • L. Lanza,
  • M. Leali,
  • P. Lenisa,
  • K. Livingston,
  • I.J.D. MacGregor,
  • D. Marchand,
  • N. Markov,
  • L. Marsicano,
  • V. Mascagna,
  • M. Mayer,
  • B. McKinnon,
  • Z.E. Meziani,
  • T. Mineeva,
  • V. Mokeev,
  • E. Munevar,
  • C. Munoz Camacho,
  • P. Nadel Turonski,
  • T.R. O'Connell,
  • M. Osipenko,
  • A.I. Ostrovidov,
  • M. Paolone,
  • L.L. Pappalardo,
  • K. Park,
  • E. Pasyuk,
  • P. Peng,
  • W. Phelps,
  • O. Pogorelko,
  • J. Poudel,
  • J.W. Price,
  • Y. Prok,
  • A.J.R. Puckett,
  • B.A. Raue,
  • M. Ripani,
  • A. Rizzo,
  • G. Rosner,
  • C. Salgado,
  • A. Schmidt,
  • R.A. Schumacher,
  • U. Shrestha,
  • D. Sokhan,
  • O. Soto,
  • N. Sparveris,
  • I.I. Strakovsky,
  • S. Strauch,
  • J.A. Tan,
  • N. Tyler,
  • M. Ungaro,
  • L. Venturelli,
  • H. Voskanyan,
  • E. Voutier,
  • N.K. Walford,
  • C.S. Whisnant,
  • M.H. Wood,
  • J. Zhang,
  • Z.W. Zhao

Journal volume & issue
Vol. 808
p. 135662

Abstract

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We report a measurement of a beam–target double-polarisation observable (E) for the γ→n→(p)→K+Σ−(p) reaction. The data were obtained impinging the circularly-polarised energy-tagged photon beam of Hall B at Jefferson Lab on a longitudinally-polarised frozen-spin hydrogen deuteride (HD) nuclear target. The E observable for an effective neutron target was determined for centre-of-mass energies 1.70≤W≤2.30 GeV, with reaction products detected over a wide angular acceptance by the CLAS spectrometer. These new double-polarisation data give unique constraints on the strange decays of excited neutron states. Inclusion of the new data within the Bonn-Gatchina theoretical model results in significant changes for the extracted photocouplings of a number of established nucleon resonances. Possible improvements in the PWA description of the experimental data with additional “missing” resonance states, including the N(2120)3/2− resonance, are also quantified.