Some properties of heavy lepton families

The simplest four-quark SU(2)xU(1) models with an anomalyfree heavy lepton sector can have two charged heavy leptons and one or two new neutral leptons. Such models also explain the rise in R (the ratio of hadronic to muon pair production in e+e--collisions). The SPEAR eμ-cross-section is consistent with two charged leptons of masses m1=1.66+0.21-0.05 GeV and m2-m1<0.59 GeV. We study some consequences of different choices of leptonic numbers for L1 and L2. In particular, we derive: the leptonic decay width when several final state leptons are massive; the cross-section for e+e-→L1antiL2 production; the branching ratio for e+e-→L2antiL2→μ+-e-+e+e-+ missing energy. (author)