NA64 is an active target experiment that utilizes high-intensity electron, positron, and muon beams generated by the collision of high-energy protons from the CERN Super Proton Synchrotron (SPS) with a target and subsequently guided to the NA64 detector. The experiment primarily employs the missing energy technique to search for dark matter particles in the sub-GeV mass range and other physics...
I will describe theories with low scale seesaw mechanisms implemented to generate the SM fermion mass hierarchy. In the first part of my talk, I will explain an extended 2HDM theory where the tree level Universal seesaw and Zee-Babu mechanisms generate the SM charged fermion mass hierarchy and tiny active neutrino masses, respectively. The theory is consistent with SM fermion masses and...
