Physics Letters B (Oct 2018)

Determination of N* amplitudes from associated strangeness production in p+p collisions

  • R. Münzer,
  • L. Fabbietti,
  • E. Epple,
  • S. Lu,
  • P. Klose,
  • F. Hauenstein,
  • N. Herrmann,
  • D. Grzonka,
  • Y. Leifels,
  • M. Maggiora,
  • D. Pleiner,
  • B. Ramstein,
  • J. Ritman,
  • E. Roderburg,
  • P. Salabura,
  • A. Sarantsev,
  • Z. Basrak,
  • P. Buehler,
  • M. Cargnelli,
  • R. Čaplar,
  • H. Clement,
  • O. Czerwiakowa,
  • I. Deppner,
  • M. Dželalija,
  • W. Eyrich,
  • Z. Fodor,
  • P. Gasik,
  • I. Gašparić,
  • A. Gillitzer,
  • Y. Grishkin,
  • O.N. Hartmann,
  • K.D. Hildenbrand,
  • B. Hong,
  • T.I. Kang,
  • J. Kecskemeti,
  • Y.J. Kim,
  • M. Kirejczyk,
  • M. Kiš,
  • P. Koczon,
  • R. Kotte,
  • A. Lebedev,
  • A. Le Fèvre,
  • J.L. Liu,
  • V. Manko,
  • J. Marton,
  • T. Matulewicz,
  • K. Piasecki,
  • F. Rami,
  • A. Reischl,
  • M.S. Ryu,
  • P. Schmidt,
  • Z. Seres,
  • B. Sikora,
  • K.S. Sim,
  • K. Siwek-Wilczyńska,
  • V. Smolyankin,
  • K. Suzuki,
  • Z. Tymiński,
  • P. Wagner,
  • I. Weber,
  • E. Widmann,
  • K. Wiśniewski,
  • Z.G. Xiao,
  • T. Yamasaki,
  • I. Yushmanov,
  • P. Wintz,
  • Y. Zhang,
  • A. Zhilin,
  • V. Zinyuk,
  • J. Zmeskal

Journal volume & issue
Vol. 785
pp. 574 – 580

Abstract

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We present the first determination of the energy-dependent amplitudes of N⁎ resonances extracted from their decay in KΛ pairs in p+p→pK+Λ reactions. A combined Partial Wave Analysis of seven data samples with exclusively reconstructed p+p→pK+Λ events measured by the COSY-TOF, DISTO, FOPI and HADES Collaborations in fixed target experiments at kinetic energies between 2.14 to 3.5 GeV is used to determine the amplitude of the resonant and non-resonant contributions into the associated strangeness final state. The contribution of seven N⁎ resonances with masses between 1650 MeV/c2 and 1900 MeV/c2 for an excess energy between 0 and 600 MeV has been considered. The Σ–p cusp and final state interactions for the p–Λ channel are also included as coherent contributions in the PWA. The N⁎ contribution is found to be dominant with respect to the phase space emission of the pKΛ+ final state at all energies demonstrating the important role played by both N⁎ and interference effects in hadron–hadron collisions. Keywords: Partial wave analysis, Resonance, Hadrons, Strangeness, Scattering length, Hyperon–nucleon interaction