Responses of quark-antiquark interaction and heavy quark dynamics to magnetic field

TL;DR

This paper studies how magnetic fields in heavy-ion collisions affect heavy quark interactions and dynamics in the quark-gluon plasma, revealing anisotropic effects and the importance of non-perturbative interactions at various temperatures.

Contribution

It provides a detailed analysis of the anisotropic modifications to heavy quark potential and diffusion coefficients in a magnetized QGP, incorporating both perturbative and non-perturbative effects beyond the lowest Landau level approximation.

Findings

Imaginary part of heavy quark potential is more negative perpendicular to magnetic field.

Heavy quark momentum diffusion becomes anisotropic and approaches isotropy at high temperatures.

Non-perturbative interactions are crucial at low temperatures for accurate modeling.

Abstract

We investigate the impact of the magnetic field generated by colliding nuclei on heavy quark-antiquark interactions and heavy quark dynamics in the quark-gluon plasma (QGP). By means of hard-thermal-loop resummation technique combined with dimension-two gluon condensates, the static heavy quark potential and heavy quark momentum diffusion coefficient, which incorporate both perturbative and non-perturbative interactions between heavy quarks and the QGP medium, are computed beyond the lowest Landau level approximation. We find that the imaginary part of the heavy quark potential in the magnetic field exhibits significant anisotropy. Specifically, the absolute value of the imaginary part is larger when the quark-antiquark separation is aligned perpendicular to the magnetic field direction, compared to when it is aligned parallel to the magnetic field direction. The heavy quark momentum diffusion coefficient in the magnetized QGP medium also becomes anisotropic. As the temperature rises, the influence of higher Landau levels becomes increasingly significant, resulting in a decrease in the anisotropy ratio of the heavy quark momentum diffusion coefficient to values even below 1. At sufficiently high temperatures, this ratio ultimately approaches 1. The non-perturbative interactions are indispensable for understanding heavy quark dynamics in the low-temperature region. We also study the response of viscous quark matter to the magnetic field and explore its implications for heavy quark potential, thermal decay widths of quarkonium states, as well as heavy quark momentum diffusion coefficient.