INDUCED SECOND CLASS CURRENTS IN τ DECAYS

We present a calculation of second class (SC) effects in τ decays induced by QCD corrections to the weak vertex [Formula: see text]. We find that the induced SC form factors behave like (m d − m u )/q 2 (q the momentum transfer, and m q the q-quark mass), which give branching ratios of O(10 −6 ) and O(10 −8 ) for the scalar and pseudotensor SC decays, respectively.