EXTENDING SENSITIVITY FOR LOW-MASS NEUTRAL HEAVY-LEPTON SEARCHES

We point out the importance of two-body final states of weak isosingle t neutral heavy leptons predicted in several models of new physics bey ond the standard model. We concentrate on muon-type neutral heavy lept ons L-mu(0) with a mass M<2 GeV that can be searched for with increase d sensitivity at a new round of neutrino experiments at CERN and Fermi lab. Providing explicit decay rate formulas for the ee nu, e mu nu, mu mu nu, pi mu, rho mu, and a(1) mu final states, we use general scalin g features to estimate the sensitivity of L-mu(0) searches in current and future experiments, emphasizing the importance of the pi mu decay mode.