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arXiv · 1312.5803

The near threshold $π^- p \to ηn$ reaction in an effective Lagrangian approach

Qi-Fang Lü·Xiao-Hao Liu·Ju-Jun Xie·De-Min Li
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Abstract

The near threshold $π^- p \to ηn$ reaction is studied within an effective Lagrangian approach and the isobar model. By considering the contributions from $s$- and $u$-channel nucleon pole and $N^{*}(1535)$ resonance, the total and differential cross sections of the $π^- p \to ηn$ reaction near threshold are calculated. Our theoretical results can fairly reproduce the current experimental data. It is also shown that while the center-of-mass energy lies in the range from the reaction threshold up to $1.65$ GeV, $s$-channel $N^{*}(1535)$ resonance plays the dominant role. The effect from nucleon pole is found to be small but the interference terms between the $N^*(1535)$ resonance and the nucleon pole are significant. The contributions from $t$-channel processes are negligible in the present calculation.

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Qi-Fang Lü, Xiao-Hao Liu, Ju-Jun Xie, De-Min Li. 2013-12-20. The near threshold $π^- p \to ηn$ reaction in an effective Lagrangian approach. https://doi.org/10.1142/s0217732314500126

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