Jet Quenching Parameter via Soft Collinear Effective Theory (SCET)

TL;DR

This paper uses Soft Collinear Effective Theory (SCET) to analyze how energetic partons gain transverse momentum in quark-gluon plasma, providing a theoretical framework for understanding jet quenching.

Contribution

It introduces a SCET-based method to calculate the jet quenching parameter , linking it to Wilson line correlators without operator ordering ambiguities.

Findings

The transverse momentum distribution is given by the Fourier transform of Wilson line correlators.

Operator ordering subtleties do not affect the  value in strongly coupled N=4 SYM plasma.

The approach clarifies the theoretical basis for jet quenching calculations.

Abstract

We analyze the transverse momentum broadening in the absence of radiation of an energetic parton propagating through quark-gluon plasma via Soft Collinear Effective Theory (SCET). We show that the probability for picking up transverse momentum k_\perp is given by the Fourier transform of the expectation value of two transversely separated light-like path-ordered Wilson lines. The subtleties about the ordering of operators do not change the \hat q value for the strongly coupled plasma of N=4 SYM theory.