Abstract:
Abstract: Results are reported from a search for the lepton flavor violating decay τ → 3µ
in proton-proton collisions at √
s = 13 TeV. The data sample corresponds to an integrated
luminosity of 33.2 fb−1
recorded by the CMS experiment at the LHC in 2016. The search
exploits τ leptons produced in both W boson and heavy-flavor hadron decays. No significant excess above the expected background is observed. An upper limit on the branching
fraction B(τ → 3µ) of 8.0 × 10−8
at 90% confidence level is obtained, with an expected
upper limit of 6.9 × 10−8
.
