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

Arnold, Peter·Gorda, Tyler·Iqbal, Shahin
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Abstract

Consider the in-medium splitting g → 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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Arnold, Peter, Gorda, Tyler, Iqbal, Shahin. 2022-04-14. The LPM effect in sequential bremsstrahlung: analytic results for sub-leading (single) logarithms. https://doi.org/10.1007/jhep04(2022)085

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