Analysis of the $\Xi_c^* \bar K$ molecular pentaquark state by its electromagnetic properties

TL;DR

This paper investigates the electromagnetic properties of the $\\Xi_c^* \\bar K$ molecular pentaquark state using QCD light-cone sum rules to understand its internal structure and quantum numbers.

Contribution

It provides the first calculation of magnetic dipole, electric quadrupole, and magnetic octupole moments for the $\\Xi_c^* \\bar K$ state assuming a molecular structure with specific quantum numbers.

Findings

Magnetic dipole moment: 0.15^{+0.04}_{-0.03} \, \mu_N

Electric quadrupole moment: (-0.93^{+0.22}_{-0.17})\times 10^{-3} \, \rm{fm^2}

Magnetic octupole moment: (-0.45^{+0.10}_{-0.09})\times 10^{-4} \, \rm{fm^3}

Abstract

We are systematically studying the electromagnetic characteristics of multiquark systems to shed light on their internal structure, whose nature and quantum numbers are controversial. In this study, we investigate the magnetic dipole, electric quadrupole, and magnetic octupole moments of the $\Xi_c^*\bar K$ state within the context of the QCD light-cone sum rule. During this analysis, we posit that the $\Xi_c^*\bar K$ state assumes a molecular structure with quantum numbers $J^P = \frac{3}{2}^-$. The extracted outcomes are given as $\mu_{\Xi_c^*\bar K} = 0.15^{+0.04}_{-0.03}\,\mu_N$, $\mathcal{Q}_{\Xi_c^*\bar K} = (-0.93^{+0.22}_{-0.17})\times 10^{-3}\,\rm{fm^2}$, and $\mathcal{O}_{\Xi_c^*\bar K} = (-0.45^{+0.10}_{-0.09})\times 10^{-4}\,\rm{fm^3}$. The findings of this study, when considered alongside other pertinent characteristics, may assist in elucidating the nature of this controversial phenomenon.