Search for heavy neutral leptons in W+→μ+μ±jet decays

Roel Aaij, Carlos Abellán Beteta, Thomas Ackernley, Bernardo Adeva, Marco Adinolfi, Hossein Afsharnia, Christine Angela Aidala, Salvatore Aiola, Ziad Ajaltouni, Simon Akar, Johannes Albrecht, Federico Alessio (+979 others)
A search is performed for heavy neutrinos in the decay of a W boson into two muons and a jet. The data set corresponds to an integrated luminosity of approximately 3.0 fb −1 of proton-proton collision data at centre-of-mass energies of 7 and 8 TeV collected with the LHCb experiment. Both same-sign and opposite-sign muons in the final state are considered. Data are found to be consistent with the expected background. Upper limits on the coupling of a heavy neutrino with the Standard Model
more » ... o are set at 95% confidence level in the heavy-neutrino mass range from 5 to 50 GeV/c 2 . These are of the order of 10 −3 for lepton-number-conserving decays and of the order of 10 −4 for lepton-number-violating heavy-neutrino decays.
doi:10.18154/rwth-2021-04300 fatcat:moiacuncvbamdczx2blactgi2q