arXiv:1910.00749
Top quark as a probe of heavy Majorana neutrino at the LHC and future collider
LEP constraints: |VeN,µN|2< O(10-5) for 80 < mN < 205 GeV
Consider pp → tt → 2b l+ l+ + 4j
with pT(leptons) > 10 GeV, pT(jets) > 15 GeV, MET<25 GeV, 1 b-jet pT > 25 GeV