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arXiv · 0808.2767

Simple Formula for High-Energy Gluon Bremsstrahlung in a Finite, Expanding Medium

Peter Arnold
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Abstract

Previous authors have considered the problem of the medium effects on single gluon bremsstrahlung associated with producing a high-energy particle in a finite, time-dependent QCD plasma. Working to leading logarithmic order, I show that the result for the bremsstrahlung gluon spectrum can be cast into a remarkably simple form in the general case. I similarly analyze the process of pair production. Also, I comment on the radius of convergence of the opacity expansion in cases where the leading-log approximation holds, showing that the opacity expansion does not converge when the thickness of the plasma is greater than roughly the bremsstrahlung formation time. Additionally, as a special bonus -- available for a limited time only while supplies last! -- I summarize translations between the notation used by a few of the groups who have worked on this and related problems.

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Peter Arnold. 2009-03-05. Simple Formula for High-Energy Gluon Bremsstrahlung in a Finite, Expanding Medium. https://doi.org/10.1103/physrevd.79.065025

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