Magnetic dipole moments of the singly-heavy baryons with spin-$\frac{1}{2}$ and spin-$\frac{3}{2}$

TL;DR

This paper calculates the magnetic dipole moments of singly-heavy baryons with different spins using QCD light-cone sum rules, providing insights into their internal quark structure and electromagnetic properties.

Contribution

It offers the first comprehensive analysis of magnetic dipole moments for both spin-1/2 and spin-3/2 singly-heavy baryons using QCD sum rules, including contributions from individual quark sectors.

Findings

Magnetic moments of spin-1/2 sextet baryons are dominated by light quarks.

Heavy quark contributions are significant in anti-triplet and spin-3/2 sextet baryons.

Electric quadrupole and magnetic octupole moments are non-zero, indicating non-spherical charge distributions.

Abstract

The electromagnetic characteristics of singly-heavy baryons at low energies are responsive to their internal composition, structural configuration, and the associated chiral dynamics of light diquarks. To gain further insight, experimentalists are attempting to measure the magnetic and electric dipole moments of charm baryons at the LHC. In view of these developments, we conducted an extensive analysis of the magnetic dipole moments of both $\rm{J^P}=\frac{1}{2}^+$ and $\rm{J^P}=\frac{3}{2}^+$ singly-heavy baryons by means of the QCD light-cone sum rules. Our findings have been compared with other phenomenological estimations that could prove a valuable supplementary resource for interpreting the singly-heavy baryon sector. To shed light on the internal structure of these baryons we study the contributions of the individual quark sectors to the magnetic dipole moments. It was observed that the magnetic dipole moments of the spin-$\frac{1}{2}$ sextet singly-heavy baryons are governed by the light quarks. Conversely, the role of the heavy quark is significantly enhanced for the spin-$\frac{1}{2}$ anti-triplet and spin-$\frac{3}{2}$ sextet singly-heavy baryons. The contribution of light and heavy quarks is observed to have an inverse relationship. The signs of the magnetic dipole moments demonstrate the interaction of the spin degrees of freedom of the quarks. The opposing signs of the light and heavy-quark magnetic dipole moments imply that the spins of these quarks are anti-aligned with respect to each other in the baryon. As a byproduct, the electric quadrupole and magnetic octupole moments of spin-$\frac{3}{2}$ singly-heavy baryons are also calculated. We ascertained the existence of non-zero values for the electric quadrupole and magnetic octupole moments of these baryons, indicative of a non-spherical charge distribution.