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arXiv · 0706.3543

Study of π^{-}p \to ηn at low energies in a chiral constituent quark model

Xian-Hui Zhong·Qiang Zhao·Jun He·Bijan Saghai
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Abstract

A chiral quark model approach is extended to the study of the $πN$ scattering at low energies. The process of $π^{-}p \to ηn$ near threshold is investigated. The model is successful in describing the differential cross sections and total cross section near the $η$ production threshold. The roles of the resonances in $n\leq 2$ shells are clarified. Near threshold, the $S_{11}(1535)$ dominates the reactions, while the interferences from the $S_{11}(1650)$ turn out to be destructive around $W\lesssim 1.6$ GeV. The $D_{13}(1520)$ is crucial to give correct shapes of the differential cross sections. The nucleon pole term contributions are significant. The $P_{11}(1710)$ plays an important role around the c.m. energy $W=1.7$ GeV, it is crucial to produce an enhancement in the region of $W>1.6$ GeV as suggested by the data for total cross section. The $t$-channel is negligible in the reactions.

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Xian-Hui Zhong, Qiang Zhao, Jun He, Bijan Saghai. 2007-11-18. Study of π^{-}p \to ηn at low energies in a chiral constituent quark model. https://doi.org/10.1103/physrevc.76.065205

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