Observing Higgs boson production through its decay into gamma-rays: A messenger for Dark Matter candidates

Abstract

In this Letter, we study the gamma-ray signatures subsequent to the production of a Higgs boson in space by dark matter annihilations. We investigate the cases where the Higgs boson is produced at rest or slightly boosted and show that such configurations can produce characteristic bumps in the gamma-ray data. These results are relevant in the case of the Standard Model-like Higgs boson provided that the dark matter mass is about 63 GeV, 109 GeV or 126 GeV, but can be generalised to any other Higgs boson masses. Here, we point out that it may be worth looking for a 63 GeV line since it could be the signature of the decay of a Standard Model-like Higgs boson produced in space, as in the case of a di-Higgs final state if m_DM ~ 126 GeV. We show that one can set generic constraints on the Higgs boson production rates using its decay properties. In particular, using the Fermi-LAT data from the galactic center, we find that the dark matter annihilation cross section into gamma + a Standard Model-like Higgs boson produced at rest or near rest cannot exceed ~ a few 10^-25 cm^3/s or ~ a few 10^-27 cm^3/s respectively, providing us with information on the Higgs coupling to the dark matter particle. We conclude that Higgs bosons can indeed be used as messengers to explore the dark matter mass range.