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Collinear Divergences at One-loop Order for External Particles in a Heat-bath

Saumen Datta·Sourendu Gupta·V. Ravindran
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Abstract

In hard interactions between external particles incident on a heat-bath, we show that large logarithms are generated when a radiated or absorbed gauge boson is collinear with the initial fermion momentum. These logarithms can be absorbed into process independent splitting/absorption probabilities. Unlike the zero-temperature case, however, they depend explicitly on the temperature and the scale of the interaction.

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Saumen Datta, Sourendu Gupta, V. Ravindran. 1996-09-19. Collinear Divergences at One-loop Order for External Particles in a Heat-bath. https://arxiv.org/abs/hep-ph/9609407

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