부산대학교 도서관

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 at s = 13 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. [ABSTRACT FROM AUTHOR]