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arXiv · nucl-th/0309023

Pentaquark baryon production from photon-neuteron reactions

W. Liu·C. M. Ko
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Abstract

Extending the hadronic Lagrangians that we recently introduced for studying pentaquark $Θ^+$ baryon production from meson-proton, proton-proton, and photon-proton reactions near threshold to include the anomalous interaction between $γ$ and $K^*K$, we evaluate the cross section for $Θ^+$ production from photon-neutron reactions, in which the $Θ^+$ was first detected in the SPring-8 experiment in Japan and the CLAS experiment at Thomas Jefferson National Laboratory. With empirical coupling constants and form factors, and assuming that the decay width of $Θ^+$ is 20 MeV, the predicted cross section is found to have a peak value of about 280 nb, which is substantially larger than that for $Θ^+$ production from photon-proton reactions.

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W. Liu, C. M. Ko. 2003-09-10. Pentaquark baryon production from photon-neuteron reactions. https://doi.org/10.1016/j.nuclphysa.2004.06.028

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