Majorana vs. Dirac sterile neutrinos lighter than MW at the LHC

• Published in: Journal of physics. Conference series 2017-09, Vol.888 (1)
• Main Authors: Dib, C O, Kim, C S, Wang, K, Zhang, J
• Format: Article
• Language: English
• Subjects: Energy spectra; Leptons; Neutrinos; Physics
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/888/1/012157

We propose to study the leptonic decays W± → e±e±µ∓ ν and W± → µ±µ±e∓ ν at the LHC to discover sterile neutrinos with masses below MW, and discriminate their Majorana or Dirac character. These decays are induced by a sterile neutrino N that goes on mass shell in the intermediate state. We find that, even though the final (anti-)neutrino goes undetected and thus lepton number is unchecked, one can distinguish between the Majorana vs. Dirac character of the intermediate sterile neutrino by comparing the production of e±e±µ∓ vs. µ±µ±e∓, provided the N-e and N-µ mixings are different enough. Alternatively, one can also distinguish the Majorana vs. Dirac character by studying the energy spectra of the opposite charge lepton, a method that works even if the N-e and N-µ mixings are equal.