Time and date: Tuesday December 1st @ 16:00 (CET)
Speaker: Julia Harz (TUM)
Title: Constraining lepton-number violating interactions in rare kaon decays.
Abstract: The nature of neutrinos and especially the origin of their masses are crucial open questions in particle physics. If neutrinos are of Majorana type, lepton-number violating (LNV) interactions areexpected. In this context, neutrinoless double beta decay is considered to be the most sensitive probe, however, it is sensitive to LNV interactions among first generation fermions only. I will
discuss the possibility to constrain lepton-number violating operators with the rare kaon decay K→πνν. Within the Standard Model effective field theory with only light active Majorana neutrinos, I will present limits on the scale of new physics based on the results of the past E949 experiment as well as on the currently operating experiments NA62 and KOTO. I will discuss the specific signature of scalar currents in K→πνν arising from the LNV nature of the operators and their implications on the experimental sensitivity, stressing the need for dedicated searches for beyond the SM currents.