Initial state radiation in Majorana Dark Matter annihilations

Andrea De Simone
2011
Article

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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Andrea De Simone
2011
Article

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https://infoscience.epfl.ch/record/170658?ln=fr

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