Magnetic moments of the spin-1/2 doubly charmed baryons in covariant baryon chiral perturbation theory

TL;DR

This paper calculates the magnetic moments of doubly charmed baryons using covariant baryon chiral perturbation theory, incorporating recent lattice QCD data and various models to determine key parameters, and compares results with other approaches.

Contribution

It introduces a covariant chiral perturbation theory approach with an extended-on-mass-shell scheme to predict magnetic moments, integrating lattice QCD data and different models for parameter determination.

Findings

Predicted magnetic moments for $ ext{Xi}^d_{cc}$ and $ ext{Xi}^s_{cc}$ baryons.

Identified inconsistencies between lattice QCD results and quark model predictions.

Compared results with heavy baryon chiral perturbation theory and other methods.

Abstract

Inspired by the recent discovery of the $\Xi_{cc}^{++}$ by the LHCb Collaboration, we study the magnetic moments of the spin-1/2 doubly charmed baryons up to the next-to-leading order in covariant baryon chiral perturbation theory with the extended-on-mass-shell renormalization scheme. There are three low energy constants at this order, $a_1$, $a_2$ and $g_a$. The latest lattice QCD simulations allow us to fix a combination of $a_1$ and $a_2$, while the axial-vector coupling $g_a$ can be determined in three different ways, either by fitting to the lattice QCD data, or by the quark model, or by the heavy antiquark diquark symmetry. The magnetic moments of the spin-1/2 doubly charmed baryons $\Xi^d_{cc}$ and $\Xi^s_{cc}$ can then be predicted. We compare our results with those obtained in the heavy baryon chiral perturbation theory and other approaches, and point out some inconsistencies between the lattice QCD simulations and the quark model.