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

Abstract

In the scenario that 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 a simple DM model where the DM candidate is a complex scalar boson. The model contains a new complex gauge singlet scalar boson and a new fermion whose gauge charge is the same as the right-handed down-type quark. We dub the new fermion the bottom partner. These new particles have Yukawa interactions with the SM down-type quarks. The DM candidate interacts with the SM particles through the Yukawa interactions. The Yukawa interactions are not only relevant to the annihilation process of the DM but also contribute to the flavor physics, such as the ∆F = 2 processes. In addition, the flavor alignment of the Yukawa couplings is related to the decay modes of the bottom partner, and thus we can find the explicit correlations among the physical observables in DM physics, flavor physics, and the signals at the LHC. We survey the ∆F = 2 processes based on the numerical analyses of the thermal relic density, the direct detection of the DM, and the current LHC bounds. We investigate the perturbative bound on the Yukawa coupling as well. A Study of a fermionic DM model with extra scalar quarks is also given for comparison.

Hidden sector behind the CKM matrix

“…In our scenario, F should be at least O(10) TeV, to avoid too large deviations in the K 0 -K 0 mixing and the EDM, so that our parameters are out of the region analyzed in Ref. [34].…”

“…It is interesting that this hierarchical Yukawa couplings, λ i , have been proposed in Ref. [34], motivated by DM physics and flavor physics.…”

“…The heavy F mass of O(10)-TeV, however, suppresses the annihilation, so that the main annihilation process is given by the interaction with the SM Higgs in Eq. (34). In order to achieve the observed relic abundance of DM, DM mass should be less than O(10) TeV, to respect the perturbativity of λ X [48].…”

“…The authors of Ref. [34] concentrate on the relatively light F case, and do the integrated research of the LHC physics, the flavor physics, and the DM physics. In our scenario, F should be at least O(10) TeV, to avoid too large deviations in the K 0 -K 0 mixing and the EDM, so that our parameters are out of the region analyzed in Ref.…”

Operators from flavored dark sectors running to low energy

“…The purpose of this paper is to extend the analysis of the running and mixing of the dark sector EFT operators supposing the mediator to be heavy and flavorful. Such a mediator has already been considered in the framework of flavored Dark Matter (see for instance [24][25][26][27][28][29][30][31][32][33][34][35][36][37]), but the running of the EFT has never been considered before. We keep our analysis as general as possible, without committing to a specific dark sector or requiring Dark Matter to be present.…”