Search for long-lived heavy neutrinos in the decays of B mesons produced in proton-proton collisions at s = 13 TeV


Hayrapetyan A., Tumasyan A., Adam W., Andrejkovic J., Bergauer T., Chatterjee S., ...Daha Fazla

Journal of High Energy Physics, cilt.2024, sa.6, 2024 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 2024 Sayı: 6
  • Basım Tarihi: 2024
  • Doi Numarası: 10.1007/jhep06(2024)183
  • Dergi Adı: Journal of High Energy Physics
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, INSPEC, zbMATH, Directory of Open Access Journals, Nature Index
  • Anahtar Kelimeler: Beyond Standard Model, Hadron-Hadron Scattering, Lifetime
  • Yıldız Teknik Üniversitesi Adresli: Evet

Özet

A search for long-lived heavy neutrinos (N) in the decays of B mesons produced in proton-proton collisions at s = 13 TeV is presented. The data sample corresponds to an integrated luminosity of 41.6 fb−1 collected in 2018 by the CMS experiment at the CERN LHC, using a dedicated data stream that enhances the number of recorded events containing B mesons. The search probes heavy neutrinos with masses in the range 1 < mN < 3 GeV and decay lengths in the range 10−2 < cτN < 104 mm, where τN is the N proper mean lifetime. Signal events are defined by the signature B → ℓBNX; N → ℓ±π∓, where the leptons ℓB and ℓ can be either a muon or an electron, provided that at least one of them is a muon. The hadronic recoil system, X, is treated inclusively and is not reconstructed. No significant excess of events over the standard model background is observed in any of the ℓ±π∓ invariant mass distributions. Limits at 95% confidence level on the sum of the squares of the mixing amplitudes between heavy and light neutrinos, |VN|2, and on cτN are obtained in different mixing scenarios for both Majorana and Dirac-like N particles. The most stringent upper limit |VN|2 < 2.0 × 10−5 is obtained at mN = 1.95 GeV for the Majorana case where N mixes exclusively with muon neutrinos. The limits on |VN|2 for masses 1 < mN < 1.7 GeV are the most stringent from a collider experiment to date.