Study on Vector Mediator Top-philic Dark Matter

We conducted a study on a simplified dark matter (DM) model that introduces a vector-like intermediate particle, facilitating exclusive interactions between DM and the top quark in the Standard Model (SM). The analysis focused on the relic density of Dirac-type fermion DM and highlighted the complementary role of direct detection (DD) in constraining the DM model. Notably, in instances when DM mass is small, the tree-level two-body annihilation process experiences suppression. In such scenarios, the contributions of the three-body process and the one-loop process dominate the relic abundance. Concerning DD, calculations were performed for the two-loop contribution to the DM-gluon interaction, yielding the corresponding spin-independent scattering cross-section.