Savino Longo

17 July 2023
31st International Symposium on Lepton Photon Interactions at High Energies

Abstract: Belle has unique reach for a broad class of models that postulate the existence of dark matter particles with MeV—GeV masses. In addition, the low-background environment of electron-positron collisions and an hermetic detector make Belle II the premier experiment for studying tau-lepton physics. This talk presents recent world-leading results from Belle II searches for Z` dark decays and long-lived (pseudo) scalars in B decays. In addition, the world’s most precise determination of the tau lepton mass and searches for tau decays into a scalar non-SM particle and a lepton are reported.