On the use of running ${\alpha }_s$ in calculations of radiative energy loss of fast partons in a quark-gluon plasma

Abstract

The incorporation of running ${\alpha }_s$ for the gluon emission vertex in calculations of radiative parton energy loss in a quark-gluon plasma is discussed. It is argued that the virtuality scale for running ${\alpha }_s$ for induced gluon emission is determined by the square of the transverse momentum of the emitted gluon rather than by the square of the invariant mass of the final two-parton state often used in the literature.

Comments: 5 pages, 2 figures, published in JETP Letters