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arXiv · 0903.3683

Momentum Broadening of a Fast Parton in a Perturbative Quark-Gluon Plasma

A. Majumder·B. Müller·St. Mrowczynski
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Abstract

The average transverse momentum transfer per unit path length to a fast parton scattering elastically in a perturbative quark-gluon plasma is related to the radiative energy loss of the parton. We first calculate the momentum transfer coefficient $\hat q$ in terms of a classical Langevin problem and then define it quantum-mechanically through scattering matrix element. After treating the well known case of a quark-gluon plasma in equilibrium we consider an off-equilibrium unstable plasma. As a specific example, we treat the two-stream plasma with unstable modes of longitudinal chromoelectric field. In the presence of the instabilities, $\hat q$ is shown to exponentially grow in time.

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A. Majumder, B. Müller, St. Mrowczynski. 2009-11-19. Momentum Broadening of a Fast Parton in a Perturbative Quark-Gluon Plasma. https://doi.org/10.1103/physrevd.80.125020

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