Published March 2013 | Version v1
Journal article

On the ΣN cusp in the pp → pK+Λ reaction

  • 1. Atomic Energy Authority NRC Cairo, Cairo (Egypt)
  • 2. Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany)
  • 3. Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany)
  • 4. Physikalisches Institut Justus-Liebig-Universitaet, Giessen (Germany)
  • 5. University of Tuebingen, Kepler Center for Astro and Particle Physics, Tuebingen (Germany)
  • 6. Physikalisches Institut der Universitaet Tuebingen, Tuebingen (Germany)
  • 7. Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen (Germany)
  • 8. Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany)
  • 9. Forschungszentrum Juelich, Institute for Advanced Simulation, Juelich (Germany)
  • 10. Forschungszentrum Juelich, Zentralinstitut fuer Elektronik, Juelich (Germany)

Description

Measurements of the pp → pK + Λ reaction at Tp = 2.28 GeV have been carried out at COSY-TOF. In addition to the Λp FSI and N * resonance excitation effects a pronounced narrow structure is observed in the Dalitz plot and in its projection on the p Λ invariant mass. The strongly asymmetric structure appears at the pp → NK + Σ threshold and is interpreted as the ΣN cusp effect. The observed width of about 20 MeV/c 2 is substantially broader than anticipated from previous measurements as well as theoretical predictions. Angular distributions of this cusp structure are shown to be dissimilar to those in the residual pK + Λ channel, but similar to those observed in the pK + Σ 0 channel. (orig.)

Availability note (English)

Available from: http://dx.doi.org/10.1140/epja/i2013-13041-8

Additional details

Identifiers

Publishing Information

Journal Title
European Physical Journal. A
Journal Volume
49
Journal Issue
3
Journal Page Range
p. 1-8
ISSN
1434-6001

Optional Information

Collaborations
COSY-TOF Collaboration