Radiative decay and axial-vector decay behaviors of octet pentaquark states

TL;DR

This paper calculates the radiative decay widths and axial-vector couplings of octet hidden-charm pentaquark states using a constituent quark model, revealing specific decay behaviors and smaller axial couplings compared to nucleons.

Contribution

It provides a systematic analysis of transition magnetic moments, decay widths, and axial-vector couplings of octet pentaquark states, highlighting their decay patterns and differences from nucleons.

Findings

Decay widths of certain processes are close in value.

Some decay processes have widths close to zero.

Axial-vector couplings are generally smaller than those of nucleons.

Abstract

In this work, we systematically calculate transition magnetic moments, radiative decay widths, and axial-vector coupling constants of octet hidden-charm molecular pentaquark states with different flavor representations in constituent quark model. We discuss the relations between transition magnetic moments and decay widths for pentaquark states. For octet pentaquark states with the $8_{1f}$ and $8_{2f}$ flavor representations, decay widths of the processes $P_{\psi}|\frac{3}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\to P_{\psi}|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes0^-)}\gamma$ and $P_{\psi}|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\to P_{\psi}|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes0^-)}\gamma$ are quite close, decay widths of the $P_{\psi}|\frac{3}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\to P_{\psi}|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\gamma$ process are close to zero, and we notice that the axial-vector coupling constants of the pentaquark states are generally smaller than that of the nucleon.