PHENIICS Doctoral School Days

Re-opening dark matter windows compatible with a diphoton excess

9 mai 2016, 15:30

1h

Auditorium Pierre Lehmann (Laboratoire de l'Accélérateur Linéaire (LAL))

Panneau: 46

Poster Cosmology & Astroparticles Poster session

Orateur

M. Mathias Pierre (LPT Orsay)

Description

We investigate a simple setup in which an excess in the di-photon invariant mass distribution around $750$ GeV, as seen by the ATLAS and CMS collaborations, is originated through a pair of collimated photon pairs. In this framework a scalar state $s$ decays into two light pseudo-Goldstone bosons $a$, each of which subsequently decays into a pair of collimated photons which are misidentified as a single photon. In a minimal context of spontaneous symmetry breaking, we show that coupling a complex scalar field $\mathrm{\Phi }=(s+ia)/\sqrt{2}$ to a fermionic dark matter candidate $\chi$, also responsible for generating its mass, allows for the correct relic density in a large region of the parameter space, while not being excluded by the direct or indirect detection experiments. Moreover, the correct relic abundance can naturally co-exist with a relatively large width for the resonant field $s$.