Dilution of dark matter relic density in singlet extension models
Abstract
We study the dilution of dark matter (DM) relic density caused by the electroweak first-order phase transition (FOPT) in the singlet extension models, including the singlet extension of the standard model (xSM), of the two-Higgs-doublet model (2HDM+S) and the next-to-minimal supersymmetric standard model (NMSSM). We find that in these models the entropy released by the strong electroweak FOPT can dilute the DM density to 1/3 at most. Nevertheless, in the xSM and NMSSM where the singlet field configure is relevant to the phase transition temperature, the strong FOPT always happens before the DM freeze-out, making the dilution effect negligible for the current DM density. On the other hand, in the 2HDM+S where the DM freeze-out temperature is independent of FOPT, the dilution may salvage some parameter space excluded by excessive DM relic density or by DM direct detections.
Keywords
Cite
@article{arxiv.2207.14519,
title = {Dilution of dark matter relic density in singlet extension models},
author = {Yang Xiao and Jin Min Yang and Yang Zhang},
journal= {arXiv preprint arXiv:2207.14519},
year = {2023}
}
Comments
21 pages, 7 figures;version accepted for publication in JHEP