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arXiv · 2112.05161

The LPM effect in sequential bremsstrahlung: analytic results for sub-leading (single) logarithms

Peter Arnold·Tyler Gorda·Shahin Iqbal
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Abstract

Consider the in-medium splitting $g \to gg$ of a very high-energy gluon traversing a QCD medium, accounting for the Landau-Pomeranchuk-Migdal (LPM) effect. It has been known for some time that soft radiative corrections to that splitting generate a double-log correction to the splitting rate, whose effects can be absorbed into running of the medium parameter $\hat q$ describing the rate of transverse momentum kicks to high-energy particles due to small-angle scattering from the medium. Less has been known about sub-leading, single logarithms in this context. In this paper, we find analytic formulas for those single logs (with various caveats and clarifications).

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Peter Arnold, Tyler Gorda, Shahin Iqbal. 2021-12-09. The LPM effect in sequential bremsstrahlung: analytic results for sub-leading (single) logarithms. https://arxiv.org/abs/2112.05161

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