Electromagnetic multipole moments of the $P_c^+(4380)$ pentaquark in light-cone QCD

TL;DR

This paper computes the electromagnetic multipole moments of the $P_c^+(4380)$ pentaquark using light-cone QCD sum rules, comparing two structural models to help determine its true internal composition.

Contribution

It provides the first detailed calculation of the electromagnetic multipole moments of $P_c^+(4380)$ in two different structural models, offering a way to distinguish its true nature.

Findings

Magnetic dipole, electric quadrupole, and magnetic octupole moments are calculated.

Results differ significantly between the diquark-diquark-antiquark and molecular models.

Future experimental data can validate the proposed models and clarify the pentaquark's structure.

Abstract

We calculate the electromagnetic multipole moments of the $P_c^+(4380)$ pentaquark by modeling it as the diquark-diquark-antiquark and $\bar D^*\Sigma_c$ molecular state with quantum numbers $J^P = \frac{3}{2}^-$. In particular, the magnetic dipole, electric quadrupole and magnetic octupole moments of this particle are extracted in the framework of light-cone QCD sum rule. The values of the electromagnetic multipole moments obtained via two pictures differ substantially from each other, which can be used to pin down the underlying structure of $P_c^+(4380)$. The comparison of any future experimental data on the electromagnetic multipole moments of the $P_c^+(4380)$ pentaquark with the results of the present work can shed light on the nature and inner quark organization of this state.