Sterile neutrinos in tau lepton decays Original Research Article

We study possible contributions of heavy sterile neutrinos νh to the decays τ−→e±(μ±)π∓π−. From the experimental upper bounds on their rates we derive new constraints on the νh–ντ mixing in the mass region 140.5 MeV⩽mνh⩽1637 MeV. We discuss cosmological and astrophysical status of νh in this mass region and compare our constraints with those recently derived by the NOMAD Collaboration.