Speaker: Prof. Xiao-Gang He (NTU &  Shanghai Jiao Tong U.)
Talk title: Flavorful Dark Matter and B to K+invisible decay
Time: 2024/09/09 (Mon.) 12:30 
Place: R517, New Physics Building 

Abstract:
Recently Belle II reported the first measurement of B+ → K+ +invisible(inv), which is 2.7σ above the standard model (SM) prediction. If confirmed, this calls for new physics beyond SM. In the SM, the invisible particles are neutrino-anti-neutrino pairs. There are more possibilities when going beyond the SM. In this talk, I focus on decays to dark matter (DM) and show that the B → K+inv excess from Belle II and DM relic density can be simultaneously explained in a simple extension of the SM. The model can successfully explain the Belle II anomaly and DM relic density for TeV-scale heavy quarks with hierarchical Yukawa couplings involving b and s quarks. At the same time, it can easily satisfy other flavour physics constraints. Direct detection searches utilizing the Migdal effect constrain some of the parameter space.