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DOE OSTI · 1849330

Efficient numerical integration of thermal interaction rates

Jackson, G.·Laine, M.
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Abstract

In many problems in particle cosmology, interaction rates are dominated by 2 ↔ 2 scatterings, or get a substantial contribution from them, given that 1 ↔ 2 and 1 ↔ 3 reactions are phase-space suppressed. We describe an algorithm to represent, regularize, and evaluate a class of thermal 2 ↔ 2 and 1 ↔ 3 interaction rates for general momenta, masses, chemical potentials, and helicity projections. A key ingredient is an automated inclusion of virtual corrections to 1 ↔ 2 scatterings, which eliminate logarithmic and double-logarithmic IR divergences from the real 2 ↔ 2 and 1 ↔ 3 processes. We also review thermal and chemical potential induced contributions that require resummation if plasma particles are ultrarelativistic.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSCosmology of theories beyond the SMPhysicsQuark-gluon plasmaThermal field theory

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BibTeXRIS

Jackson, G., Laine, M.. 2021-09-20. Efficient numerical integration of thermal interaction rates. https://doi.org/10.1007/jhep09(2021)125

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