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arXiv · 1107.4453

Initial State Radiation in Majorana Dark Matter Annihilations

Paolo Ciafaloni·Marco Cirelli·Denis Comelli·Andrea De Simone·Antonio Riotto·Alfredo Urbano
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Abstract

The cross section for a Majorana Dark Matter particle annihilating into light fermions is helicity suppressed. We show that, if the Dark Matter is the neutral Majorana component of a multiplet which is charged under the electroweak interactions of the Standard Model, the emission of gauge bosons from the initial state lifts the suppression and allows an s-wave annihilation. The resulting energy spectra of stable Standard Model particles are importantly affected. This has an impact on indirect searches for Dark Matter.

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Paolo Ciafaloni, Marco Cirelli, Denis Comelli, Andrea De Simone, Antonio Riotto, Alfredo Urbano. 2011-07-22. Initial State Radiation in Majorana Dark Matter Annihilations. https://doi.org/10.1088/1475-7516%2F2011%2F10%2F034

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