In-medium dispersion relations of charmonia studied by maximum entropy method

TL;DR

This study investigates how charmonia spectral properties, including dispersion relations and peak weights, change in a medium at high temperatures using lattice QCD and the maximum entropy method, revealing mass increases but unchanged dispersion form.

Contribution

It applies the maximum entropy method to analyze in-medium charmonia spectral functions at nonzero momenta, providing new insights into their dispersion relations at high temperatures.

Findings

Masses of charmonia increase in medium.

Dispersion relations remain similar to vacuum within errors.

Peak weights show temperature-dependent behavior.

Abstract

We study in-medium spectral properties of charmonia in the vector and pseudoscalar channels at nonzero momenta on quenched lattices, especially focusing on their dispersion relation and weight of the peak. We measure the lattice Euclidean correlation functions with nonzero momenta on the anisotropic quenched lattices and study the spectral functions with the maximum entropy method. The dispersion relations of charmonia and the momentum dependence of the weight of the peak are analyzed with the maximum entropy method together with the errors estimated probabilistically in this method. We find significant increase of the masses of charmonia in medium. It is also found that the functional form of the charmonium dispersion relations is not changed from that in the vacuum within the error even at $T\simeq1.6T_c$ for all the channels we analyzed.