First Observation of the Decay tau^- -> phi K^- nu_tau
  We present the first observation of tau lepton decays to hadronic final states with a phi-meson. This analysis is based on 401 fb^-1 of data accumulated at the Belle experiment. The branching fraction obtained is B(tau- -> phi K- nu) = (4.05 +- 0.25 +- 0.26) x 10^-5. 
Belle colaboration