The melting of charmonium in a magnetic field from an effective AdS/QCD model

TL;DR

This paper investigates how a magnetic field affects the melting temperatures of different polarizations of J/psi mesons using an effective AdS/QCD model, revealing polarization-dependent melting behaviors and increased diffusion for longitudinal modes.

Contribution

It introduces a Born-Infeld modified soft-wall model to study polarization-specific melting of charmonium in magnetic fields, a novel approach in holographic QCD.

Findings

Longitudinal J/psi melts at higher temperature than deconfinement temperature.

Transverse polarizations melt at lower temperatures under magnetic fields.

Magnetic field increases the heavy quark diffusion constant for longitudinal polarization.

Abstract

We study the influence of a background magnetic field on the melting of the J/psi vector meson by introducing a Born-Infeld modification of the soft-wall model. Out of the three polarizations of the massive vector meson, we find that the longitudinal one (parallel to the applied magnetic field) melts only at an even higher temperature than the deconfinement temperature, whereas the two transverse polarizations melt at a lower temperature than in the absence of a magnetic field. We also conduct a preliminary investigation of the effect of the magnetic field on the heavy quark diffusion coefficient, showing an increased diffusion constant for the longitudinal polarization with respect to the transverse polarizations.