Dynamical study of $\pi N\to \pi\pi N$ reactions revisited

Abstract

Using the Argonne National Laboratory-The University of Osaka (ANL-Osaka) DCC model of meson-nucleon reactions, we extend the study of Phys. Rev. C 79, 025206 (2009) and Phys. Rev. C 88, 045203 (2013) to predict the cross sections of the $\pi N \to \pi \pi N$ reactions. The model was constructed by fitting only the two-body reactions: $\pi N,\gamma N \to \pi N, \eta N, K\Lambda, K\Sigma$. Thus, the results for $\pi N \to \pi \pi N$ presented here are predictions of the ANL-Osaka DCC model, which serve to examine the extent to which the forthcoming data from J-PARC can be described. This study provides information for improving the extraction of nucleon resonances that have large decay widths to $\pi\pi N$ states. We present results for the total cross sections, invariant mass distributions, and angular distributions. We also identify the observables and energy regions where the higher mass nucleon resonances in the $S_{31}$, $P_{33}$, $D_{33}$, $F_{37}$, $D_{13}$, $D_{15}$, and $F_{15}$ partial waves can be most effectively investigated.