Charged Lepton Flavour Violation in Heavy Particle DEcays

Charged lepton flavor violation is an unambiguous signature for New Physics. Here we present a summary of the theoretical and experimental status of the search for charged lepton flavor violation in heavy particle decays, in particular in the decays of the Z and Higgs bosons, and of the top quark. Decays of beyond-Standard-Model particles such as a Z' or an additional scalar particle are also discussed. Finally the prospects for such searches at proposed future electron-positron colliders are reviewed.
Comment: White paper submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)