Title: Heavy neutrino oscillation, same-sign dilepton charge asymmetry at colliders and leptogenesis

Speaker: Dr. Yongchao Zhang (Washington University in St. Louis)

Time: 10:00 AM, Jul. 2nd  (Tuesday), 2019 

Place: R319, Theoretical Physics Division

Abstract: Heavy neutrinos are essential ingredients of type-I seesaw mechanism, and the heavy neutrino mixing and associated CP phase can be directly probed at future high-energy hadron colliders, by measuring the charge asymmetry in same-sign dilepton signals which is mediated by the heavy $W_R$ boson. The high-energy LHC could probe a non-vanishing CP phase for a $W_R$ mass up to 7.2 TeV, while at future 100 TeV colliders FCC-hh and SPPC the $W_R$ mass could go up to 26 TeV. Mixing angles and CP violation in the heavy neutrino sector are crucial to generate the observed baryon asymmetry for TeV-scale resonant leptogenesis, thus the same-sign charge asymmetry measurements at colliders can be used to test leptogenesis.