Phenomenology of doublet-triplet fermionic dark matter in nonstandard cosmology and multicomponent dark sectors

TL;DR

This paper explores a doublet-triplet fermionic dark matter model within nonstandard cosmology and multicomponent sectors, analyzing how these scenarios affect relic density, collider signals, and detection constraints, revealing viable parameter spaces.

Contribution

It introduces the impact of nonstandard cosmology and multicomponent sectors on the phenomenology of doublet-triplet fermionic dark matter models, expanding understanding of their experimental viability.

Findings

Nonstandard cosmology relaxes experimental constraints, leaving large viable parameter regions.

Multicomponent dark sectors are mainly constrained by direct detection experiments.

Collider and detection constraints vary significantly between scenarios.

Abstract

We consider the doublet-triplet fermionic model in the scheme of the custodial limit when the dark matter (DM) candidate is pure doublet and lies at the electroweak scale. This scheme, despite being an appealing and promising DM model, is severely constrained by the interplay between the DM relic density constraint and the LHC measurement of the Higgs diphoton decay rate. In this work, the DM relic density is considered to arise from either a nonstandard cosmology scenario or as a part of a larger sector encompassing other DM particles, this in order to saturate the observed relic abundance. For these scenarios we investigate the impact of the new sector in different collider observables, and study constraints coming from direct detection and indirect detection of gamma-rays both in the diffuse and linelike spectrum. As a result, we find that in the nonstandard cosmology scenario most experiments impose, up to a certain point, restrictions, though large portions of the parameter space are still viable. For the multicomponent case, only direct detection imposes constraints.