Soft gluon emission from heavy quark scattering in strongly interacting quark-gluon plasma

TL;DR

This paper applies Low's theorem to study soft gluon emission from heavy quarks in a strongly interacting quark-gluon plasma, simplifying calculations and providing gauge-invariant cross sections and transport coefficients.

Contribution

It introduces a method to calculate soft gluon emission in sQGP using Low's theorem, connecting emission with elastic scattering and deriving gauge-invariant cross sections.

Findings

Derived gauge-invariant scattering cross sections.

Calculated transport coefficients including momentum drag and diffusion.

Compared gluon emission effects with elastic scattering results.

Abstract

We apply the Low's theorem to soft gluon emission from heavy quark scattering in the nonperturbative strongly interacting quark-gluon plasma (sQGP). The sQGP is described in terms of the dynamical quasi-particles and adjusted to reproduce the EoS from lQCD at finite temperature and chemical potential. Since the emitted gluon is soft and of long wavelength, it does not provide information on the detailed structure of the scattering, and only the emission from incoming and outgoing partons is enough. It simplifies the calculations making the scattering amplitude factorizable into the elastic scattering and the emission of soft gluon. Imposing a proper upper limit on the emitted gluon energy, we obtain the guage-invariant scattering cross sections of heavy quarks with the massive partons of the medium as well as their transport coefficients (momentum drag and diffusion) in the QGP and compare with those from the elastic scattering without gluon emission.