Tests for Tau's Charged-Current Structure
  The Lorentz structure of the tau lepton's charged-current can almost be completely determined by use of stage-two spin-correlation functions for the $\{\rho ^{-},\rho ^{+}\}$ and $\{a_1^{-},a_1^{+}\}$ decay modes It is possible to test for a ``(V-A) + something'' structure in the ${J^{Charged}}_{Lepton}$ current, so as to bound the scales $\Lambda$ for ``new physics" such as arising from tau weak magnetism, weak electricity, and/or second-class currents. 
Charles A. Nelson