Cosmic rays through the Higgs portal

Understand

We consider electroweak singlet dark matter with a mass comparable to the Higgs mass.

• The singlet is assumed to couple to standard matter through a perturbative coupling to the Higgs particle.
• The annihilation of a singlet with a mass comparable to the Higgs mass is dominated by proximity to the W, Z and Higgs peaks in the annihilation cross section.
• We find that the continuous photon spectrum from annihilation of a perturbatively coupled singlet in the galactic halo can reach a level of several per mil of the EGRET diffuse gamma ray flux.