The branching fractions for the major decay modes of the ~ lepton are measured from a sample of tagged ~ decays selected from ~+~ pairs produced in e+e annihilation. The decay products of one member of the ~+~ pair are used to identify the event. The opposite member of the pair is then included in the sample if it satisfies an invariant-mass cut and a charged-multiplicity cut. In this way, we attempt to select an unbiased sample of ~ decays. The sample is divided into categories based on charged- and neutral-particle multiplicities, and charged-particle identification. The branching fractions are measured simultaneously, with an unfold technique and a maximum-likelihood fit, with the sum of the branching fractions constrained to be unity. The branching fractions for the decay modes ~ ~v K and ~ ~v, K* are fixed at the world averages in the fit. The following branching fractions are measured: and B(w 9)%%uo. The total branching fraction to one charged pion plus at least one neutra1 hadron is measured to be (37. 8+1. 2+1. 0)%. Limits on allowed decay modes involving the g meson are discussed.
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