Two topics from lattice NRQCD at non-zero temperature: heavy quark mass dependence and S-wave bottomonium states moving in a thermal bath

TL;DR

This study uses NRQCD to analyze how bottomonium states behave at various temperatures and momenta in a thermal environment, revealing insights into their mass dependence and spectral properties.

Contribution

It provides new insights into the temperature and momentum dependence of bottomonium correlators and spectral functions using NRQCD and Maximum Entropy Method.

Findings

Energy of moving states shows quadratic momentum dependence.

Width of moving states remains relatively unchanged with increased momentum.

Temperature effects on correlator ratios are more significant than 20% changes in bottom quark mass.

Abstract

Using Non-Relativistic QCD (NRQCD), we study heavy quark mass dependence of S-wave and P-wave bottomonium correlators for 0.42Tc <= T <= 2.09Tc and study spectral functions of S-wave bottomonium states moving in a thermal bath at these temperatures using Maximum Entropy Method with NRQCD kernel. For the studied momentum range, the energy of moving states shows quadratic momentum-dependence and the width of moving states does not show significant changes as the momentum of bottomonium is increased. Also, we find that in correlator ratios, the temperature effect is larger than the effect caused by 20% change in the bottom quark mass.