Analysis of Theta^+ production in K^+Xe collisions

Abstract

The reaction K^+Xe->K^0pX is investigated in a meson-exchange model including rescattering of the secondary protons with the aim to analyze the evidence for the Theta^+(1540) resonance reported by the DIANA collaboration. We confirm that the kinematical cuts introduced by the DIANA collaboration efficiently suppress the background to the K^+n->K^0p reaction which may contribute to the Theta^+(1540) production. We find that these kinematical cuts do not produce a narrow structure in the K^0p effective mass spectra near 1540 MeV. We study the effect of a narrow Theta^+ resonance of both positive and negative parity in comparison with the DIANA data. We show that the K^+Xe->K^0pX calculations without Theta^+ contribution as well as the results obtained with a Theta^+ width of 1 MeV are in comparably good agreement with the DIANA results. More dedicated experiments are called for to establish this exotic baryon resonance.

9 pages, 7 figures