Coupled-channel study of γp→K+Λ

Abstract

A coupled-channel (CC) approach has been developed to investigate kaon photoproduction on the nucleon. In addition to direct K + Λ production, our CC approach accounts for strangeness production including K + Λ final state interactions with both π 0 p and π + n intermediate states. Calculations for the γp → K + Λ reaction have been performed, and compared with the recent data from SAPHIR, with emphasis on the CC effects. We show that the CC effects are significant at the level of inducing 20% changes on total cross sections; thereby, demonstrating the need to include πN channels to correctly describe the γp → K + Λ reaction.

Dynamical coupled-channels model ofK−preactions: Determination of partial-wave amplitudes

“…Our DCC model and a similar coupled-channels model developed in the Jülich πN analysis [26,27] are constrained by the meson-exchange mechanisms. Both approaches are motivated by the success of the meson-exchange models of NN interactions [28] and πN and γN reactions in the ∆ (1232) region [29][30][31][32][33][34][35][36]. Thus there are good reasons to assume that a DCC model, as formulated in Refs.…”

Photo- And Electroproduction of Kaons

“…In the effective hadron Lagrangian approach, various channels connected via the final-state interaction (the meson-baryon rescattering processes) have to be treated simultaneously to take unitarity properly into account [8,9]. In Ref.…”

Strangeness production on the nucleon

“…Recently, Chiang et al estimated the effects of coupled-channel mechanisms on the p (γ, K + ) Λ cross sections of the order of 20% [28]. Admittedly, this is a substantial effect.…”

“…In the same spirit, g K + Λp is predicted to be negative and g K + Σ 0 p positive. Consequently, we take: 28) as value for the electromagnetic Σ 0 Λ transition moment.…”

“…One had to wait until 1998, when the SAPHIR collaboration at Bonn [23,24] released the first extensive and accurate database for all three γp → K + Λ, K + Σ 0 and K 0 Σ + reactions. The results of this experiment clearly triggered renewed interest at various theoretical groups [25][26][27][28][29][30][31][32].…”