Axions and axion-like particles (ALPs) remain compelling dark matter (DM) candidates, provided that the associated Peccei-Quinn (PQ) symmetry breaking scale $f_a$ is sufficiently large to ensure cosmological stability. In this talk, I will explore a novel framework in which ALPs possess flavor-violating (FV) couplings to Standard Model (SM) quarks, allowing them to be produced via freeze-in in...
In many theoretical models, the observed matter-antimatter asymmetry originates from out-of-equilibrium decays and scatterings of heavy particles. In these scenarios, charge-parity (CP) symmetry violation arises perturbatively through the interference between tree-level and one-loop diagrams. As a result, the CP asymmetry, characterized by the parameter $\epsilon$, is suppresed by higher...