Search for heavy Majorana or Dirac neutrinos and right-handed W gauge bosons in final states with charged leptons and jets in pp collisions at √s = 13 TeV with the ATLAS detector

A search for heavy right-handed Majorana or Dirac neutrinos N_R  and heavy right-handed gauge bosons W_R  is performed in events with energetic electrons or muons, with the same or opposite electric charge, and energetic jets. The search is carried out separately for topologies of clearly separated final-state products (“resolved” channel) and topologies with boosted final states with hadronic and/or leptonic products partially overlapping and reconstructed as a large-radius jet (“boosted” channel). The events are selected from pp collision data at the LHC with an integrated luminosity of 139 fb^-1 collected by the ATLAS detector √s = 13 at TeV. No significant deviations from the Standard Model predictions are observed. The results are interpreted within the theoretical framework of a left-right symmetric model, and lower limits are set on masses in the heavy right-handed W_R boson and N_R plane. The excluded region extends to about m(W_R)  = 6.4  TeV for both Majorana and Dirac N_R neutrinos at m(N_R) < 1 TeV. N_R with masses of less than 3.5 (3.6) TeV are excluded in the electron (muon) channel at m(W_R)  =  4.8 TeV for the Majorana neutrinos, and limits of m(N_R) up to 3.6 TeV for m(W_R)  =  5.2 (5.0) TeV in the electron (muon) channel are set for the Dirac neutrinos. These constitute the most stringent exclusion limits to date for the model considered.