The LHC diphoton resonance and dark matter

TL;DR

This paper explores the potential implications of a 750 GeV diphoton resonance observed at the LHC for dark matter, analyzing how it could influence relic density and be tested by future detection experiments.

Contribution

It investigates the connection between the LHC diphoton resonance and dark matter, demonstrating compatibility with relic density and proposing methods to determine the resonance's CP nature.

Findings

Correct relic density can be achieved with a wide range of dark matter masses and couplings.

Future detection experiments can probe the CP nature of the resonance.

The resonance's properties could have significant implications for cosmology.

Abstract

A Higgs-like resonance with a mass of approximately 750 GeV has recently been observed at the LHC in its diphoton decay. If this state is not simply a statistical fluctuation which will disappear with more data, it will have important implications not only for particle physics but also for cosmology. In this note, we analyze the implications of such a resonance for the dark matter (DM). Assuming a spin 1/2 DM particle, we first verify that indeed the correct relic density can be obtain for a wide range of the particle mass and weak scale coupling that are compatible with present data. We then show that the combination of near future direct and indirect detection experiments will allow to probe the CP-nature of the mediator resonance, i.e. check whether it is a scalar or a pseudoscalar like particle.