Dark matter physics, flavor physics and LHC constraints in the dark matter model with a bottom partner

TL;DR

This paper explores a scalar dark matter model interacting via a bottom partner quark, analyzing its relic density, flavor physics implications, and LHC constraints, revealing correlations among these observables.

Contribution

It introduces a simple scalar DM model with a bottom partner, linking flavor physics, relic density, and collider signals, with detailed numerical analysis and comparison to fermionic DM models.

Findings

Correlations among DM relic density, flavor observables, and LHC signals.

Constraints on Yukawa couplings from relic density and direct detection.

Predictions for flavor-changing processes in the model.

Abstract

In the scenario that a dark matter (DM) is a weakly interacting massive particle, there are many possibilities of the interactions with the Standard Model (SM) particles to achieve the relic density of DM. In this paper, we consider one simple DM model where the DM candidate is a complex scalar and interacts with the SM particles via exchange of the Higgs particle and an extra quark, named bottom partner. The extra quark carries the same quantum number as the right-handed down-type quarks and has Yukawa couplings with the DM candidate and the right-handed down-type quarks. The Yukawa interactions are not only relevant to the thermal relic density of the DM, but also contribute to the flavor physics, such as the $\Delta F=2$ processes. In addition, the flavor alignment of the Yukawa couplings is related to the decay modes of the extra quark. Then, we can find the explicit correlations among the physical observables in DM physics, flavor physics and the signals at the LHC. Based on the numerical analyses of the thermal relic density, the direct detection of the DM and the current LHC bounds using the latest results, we survey our predictions for the $\Delta F=2$ processes. We investigate the perturbative bound on the Yukawa coupling, as well. Study of a fermionic DM model with extra scalar quarks is also given for comparison.