"Figure6 - Dirac tau" of "Search for long-lived heavy neutral leptons decaying in the CMS muon detectors in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

Expected and observed upper 95% CL limits on |VNtau|2 as functions of the HNL mass(mN) for a Dirac HNL. For these limit calculations, the HNL is assumed to mix with a single lepton flavor state only. The tau neutrino mixing limit is obtained by combining the results from the electron and muon channels. The difference between the expected and observed limits on |VNμ|2 are not visible in this figure.