Search for right-handed 𝑊 bosons and heavy neutrinos with the ATLAS experiment

A search for heavy right-handed Majorana or Dirac neutrinos (𝑁$_{R}$) and heavy right-handed 𝑊 bosons (𝑊$_{R}$) participating in the Keung-Senjanović (KS) process has been performed in events with a pair of energetic electrons or muons and two energetic jets. Events were selected from 𝑝𝑝 collision data with an integrated luminosity of 139 fb$^{-1}$ collected by √𝑠 = 13 TeV. No significant deviations from the Standard Model the ATLAS detector at expectation were observed. The results are interpreted within the theoretical framework of the Left-Right Symmetric Models (LRSM) and lower limits are set on masses of the 𝑊𝑅 and 𝑁𝑅. For Majorana electron neutrinos, the excluded region extends to a 𝑊𝑅 mass of 5.6 TeV and a 𝑁𝑅 mass of 3.4 TeV. For Majorana muon neutrinos, 𝑊𝑅 masses of up to 5.7 TeV are excluded, and 𝑁$_{R}$ masses of up to 3.6 TeV. For Dirac electron neutrinos, the excluded region extends to a 𝑊$_{R}$ mass of 6 TeV and to a 𝑁$_{R}$ mass of 3.5 TeV. For Dirac muon neutrinos, 𝑊$_{R}$ masses of up to 5.8 TeV are excluded, and 𝑁$_{R}$ masses of up to 3.7 TeV. These limits improve upon previous results in the bibliography and are currently the most stringent in the world.