Search for Majorana neutrinos in same-sign WW scattering events from pp collisions at √s=13 TeV


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Aad G., Abbott B., Abeling K., Abicht N., Abidi S., Aboulhorma A., ...Daha Fazla

European Physical Journal C, cilt.83, sa.9, 2023 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 83 Sayı: 9
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1140/epjc/s10052-023-11915-y
  • Dergi Adı: European Physical Journal C
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, INSPEC, zbMATH, Directory of Open Access Journals
  • İstanbul Üniversitesi Adresli: Evet

Özet

A search for Majorana neutrinos in same-sign WW scattering events is presented. The analysis uses s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb - 1 recorded during 2015–2018 by the ATLAS detector at the Large Hadron Collider. The analysis targets final states including exactly two same-sign muons and at least two hadronic jets well separated in rapidity. The modelling of the main backgrounds, from Standard Model same-sign WW scattering and WZ production, is constrained with data in dedicated signal-depleted control regions. The distribution of the transverse momentum of the second-hardest muon is used to search for signals originating from a heavy Majorana neutrino with a mass between 50 GeV and 20 TeV. No significant excess is observed over the background expectation. The results are interpreted in a benchmark scenario of the Phenomenological Type-I Seesaw model. In addition, the sensitivity to the Weinberg operator is investigated. Upper limits at the 95% confidence level are placed on the squared muon-neutrino–heavy-neutrino mass-mixing matrix element | VμN| 2 as a function of the heavy Majorana neutrino’s mass mN , and on the effective μμ Majorana neutrino mass | mμμ| .