This article presents a model-independent search for an additional, mostly sterile, heavy neutral lepton (HNL), that is capable of mixing with the Standard Model τ neutrino with a mixing strength of |Uτ4|2, corresponding to the absolute square of the extended Pontecorvo-Maki-Nakagawa-Sakata matrix element. Data from the BABAR experiment, with a total integrated luminosity of 424 fb-1, are analyzed using a kinematic approach that makes no assumptions on the model behind the origins of the HNL, its lifetime or decay modes. No significant signal is found. Upper limits on |Uτ4|2 at the 95% confidence level, depend on the HNL mass hypothesis and vary from 2.31×10-2 to 5.04×10-6 (with all uncertainties considered), across the mass range 100<1300 MeV/c2; the more stringent limits being placed at higher masses.

Search for heavy neutral leptons using tau lepton decays at BaBaR

Li Y.;Finocchiaro G.;Banerjee S.;Cenci R.;Gaz A.;Marchiori G.;Batignani G.;Lusiani A.
Writing – Review & Editing
;
Ferroni F.;
2023

Abstract

This article presents a model-independent search for an additional, mostly sterile, heavy neutral lepton (HNL), that is capable of mixing with the Standard Model τ neutrino with a mixing strength of |Uτ4|2, corresponding to the absolute square of the extended Pontecorvo-Maki-Nakagawa-Sakata matrix element. Data from the BABAR experiment, with a total integrated luminosity of 424 fb-1, are analyzed using a kinematic approach that makes no assumptions on the model behind the origins of the HNL, its lifetime or decay modes. No significant signal is found. Upper limits on |Uτ4|2 at the 95% confidence level, depend on the HNL mass hypothesis and vary from 2.31×10-2 to 5.04×10-6 (with all uncertainties considered), across the mass range 100<1300 MeV/c2; the more stringent limits being placed at higher masses.
2023
Settore FIS/01 - Fisica Sperimentale
Baryogenesis & leptogenesis; Extensions of fermion sector; Neutrino interactions; Neutrino mixing; Neutrino oscillations; Particle dark matter; Signatures with new fermions; Signatures with tau leptons
File in questo prodotto:
File Dimensione Formato  
PhysRevD.107.052009.pdf

accesso aperto

Tipologia: Published version
Licenza: Creative Commons
Dimensione 5.83 MB
Formato Adobe PDF
5.83 MB Adobe PDF

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11384/139386
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 5
  • OpenAlex ND
social impact