Radiative corrections to co-annihilation processes

A. Freitas

doi:10.1016/j.physletb.2007.07.019

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arXiv · 0705.4027

Radiative corrections to co-annihilation processes

A. Freitas

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Abstract

In co-annihilation scenarios, the weakly interacting dark matter particle (WIMP) is close in mass to another particle that can decay into the WIMP. As a result, both particles freeze out at roughly the same time in the early universe, and both contribute to the effective dark matter annihilation cross-section. Since the heavier particle does not need to be weakly interacting, the co-annihilation processes are in general subject to sizeable radiative corrections. Here this is analyzed for the example of neutralino-stop co-annihilation in supersymmetry. The leading QCD corrections are calculated and it is found that they have a large effect on the effective annihilation cross-section, reaching more than 50% in some regions of parameter space.

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A. Freitas. 2007-09-07. Radiative corrections to co-annihilation processes. https://doi.org/10.1016/j.physletb.2007.07.019

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