Tau Kinematics from Impact Parameters

Abstract

The momenta of $\tau$ decay products in the reaction $e^{+}{e}^{-}\to {\tau }^{+}{\tau }^{-}$ do not constrain the $\tau$ direction unambiguously. It is shown how the measurement of tracks of hadrons from semileptonic $\tau$ decays, in particular their relative impact parameters, allows to resolve this ambiguity.

Comments: 4[pag]es, 1 figure available by FAX, TTP93-14