On the direct detection of multi-component dark matter: implications of the relic abundance

TL;DR

This paper investigates how the relic abundance of multi-component dark matter influences direct detection prospects, analyzing scenarios like asymmetric dark matter and thermal freeze-out to assess experimental sensitivity and parameter extraction.

Contribution

It extends previous work by incorporating relic abundance constraints into direct detection analysis for multi-component dark matter, comparing different genesis scenarios.

Findings

Asymmetric dark matter scenario shows higher detection sensitivity.

Most scenarios have lower median sensitivity than general cases.

Thermal freeze-out scenario is less promising than asymmetric dark matter.

Abstract

Recently we studied the direct detection of multi-component dark matter with arbitrary local energy densities. Although the generation of the dark matter relic abundance is model-dependent, and in principle could be only indirectly related to direct detection, it is interesting to consider the implications of the former on the latter. In this work we conduct an extended analysis to include constraints from two natural scenarios of dark matter genesis: asymmetric dark matter and thermal freeze-out. In the first (second) case, the dark matter number (energy) densities of the different components are expected to be similar. In the case of thermal freeze-out, we assume that the global energy density scales with the local one. In our numerical analysis we analyse the median sensitivity of direct detection experiments to discriminate a two-component scenario from a one-component one, and also the precision with which dark matter parameters can be extracted. We analyse these generic scenarios for both light and heavy mediators. We find that most scenarios have a relatively suppressed maximum median sensitivity compared to the previously studied general cases. We also find that the asymmetric scenario is more promising than the thermal freeze-out one.