Radiative energy loss in the absorptive QGP: taming the long formation lengths in coherent emission

TL;DR

This paper investigates how damping in an absorptive quark-gluon plasma suppresses gluon bremsstrahlung, especially at intermediate energies, affecting energy loss calculations for heavy quarks.

Contribution

It introduces the impact of plasma damping on gluon radiation spectra, highlighting suppression effects independent of heavy-quark mass at certain energies.

Findings

Gluon bremsstrahlung spectrum is strongly suppressed at intermediate energies.

Damping effects increase with gluon damping rate and quark energy.

Suppression reduces the mass dependence of radiation spectra at larger energies.

Abstract

In an absorptive plasma, damping of radiation mechanisms can influence the bremsstrahlung formation in case of large radiation formation lengths. We study qualitatively the influence of this effect on the gluon bremsstrahlung spectrum off heavy quarks in the quark-gluon plasma. Independent of the heavy-quark mass, the spectrum is found to be strongly suppressed in an intermediate gluon energy region which grows with increasing gluon damping rate and increasing energy of the heavy quark. Thus, just as polarization effects in the plasma render the bremsstrahlung spectra independent of the quark mass in the soft gluon regime, damping effects tend to have a similar impact for larger gluon energies.