Relic density computations at NLO: infrared finiteness and thermal correction

Martin Beneke, Francesco Dighera, Andrzej Hryczuk
2014 Journal of High Energy Physics  
There is an increasing interest in accurate dark matter relic density predictions, which requires next-to-leading order (NLO) calculations. The method applied up to now uses zero-temperature NLO calculations of annihilation cross sections in the standard Boltzmann equation for freeze-out, and is conceptually problematic, since it ignores the finite-temperature infrared (IR) divergences from soft and collinear radiation and virtual effects. We address this problem systematically by starting from
more » ... non-equilibrium quantum field theory, and demonstrate on a realistic model that soft and collinear temperaturedependent divergences cancel in the collision term. Our analysis provides justification for the use of the freeze-out equation in its conventional form and determines the leading finite-temperature correction to the annihilation cross section. This turns out to have a remarkably simple structure.
doi:10.1007/jhep10(2014)045 fatcat:bkebc5w5yjestfaviifnaxyuh4