Jet quenching parameter in QCD kinetic theory
Kirill Boguslavski, Aleksi Kurkela, T. Lappi, Florian Lindenbauer, Jarkko Peuron
Abstract
We study the jet quenching parameter <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mover accent="true"> <a:mi>q</a:mi> <a:mo stretchy="false">^</a:mo> </a:mover> </a:math> in a nonequilibrium plasma using the QCD effective kinetic theory. We discuss subleading terms at large jet momentum <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"> <e:mi>p</e:mi> </e:math> , show that our expression for <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"> <g:mover accent="true"> <g:mi>q</g:mi> <g:mo stretchy="false">^</g:mo> </g:mover> </g:math> reproduces thermal results at small and large transverse momentum cutoffs for infinite <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"> <k:mi>p</k:mi> </k:math> , and construct an interpolation between these limits to be used in phenomenological applications. Using simple nonequilibrium distributions that model pertinent features of the bottom-up thermalization scenario, we analytically assess how anisotropy, underoccupation, or overoccupation affect the jet quenching parameter. Our work provides more details on the <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"> <m:mover accent="true"> <m:mi>q</m:mi> <m:mo stretchy="false">^</m:mo> </m:mover> </m:math> formula used in our preceding work [ ] and sets the stage for further numerical studies of jet momentum broadening in the initial stages of heavy-ion collisions from QCD kinetic theory. Published by the American Physical Society 2024