arXiv 0901.07712009-01-07hep-phnucl-th

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

Seung-il Nam, Hyun-Chul Kim

备注：: 16 pages, 16 figures
发表信息：: Phys.Rev.D79:034031,2009
DOI：: 10.1103/PhysRevD.79.034031

英文摘要：

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.

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