Photoproduction of Theta^+(1540,1/2^+) reexamined with new theoretical information

Abstract

We reinvestigate the photoproduction of the exotic pentaquark baryon Theta^+(1540,1/2^+) from the gamma N -> Kbar Theta^+ reaction process within the effective Lagrangian approach, taking into account new theoretical information on the K-N-Theta and K*-N-Theta coupling strengths from the chiral quark-soliton model (chiQSM). We also consider the crossing-symmetric hadronic form factor, satisfying the on-shell condition as well. Due to the sizable vector and tensor couplings for the vector kaon, g_{K* N Theta} and f_{K* N Theta}, which are almost the same with the vector coupling g_{K N Theta} ~ 0.8 for the pseudoscalar kaon, the K*-exchange contribution plays a critical role in the photon beam asymmetries.

16 pages, 16 figures

References in corpus (6)

• Further evidence for formation of a narrow baryon resonance with positive strangeness in K+ collisions with Xe nuclei
• Search for Theta+ via pi- p --> K- X reaction near production threshold
• Axial-vector transitions and strong decays of the baryon antidecuplet in the self-consistent SU(3) chiral quark-soliton model
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• Magnetic interaction induced by the anomaly in kaon-photoproductions
• K*-couplings for the antidecuplet excitation