An upper limit for the \tau–neutrino mass from \tau\rightarrow 5\pi^{\pm}\nu_{\tau} decays

An upper limit for the –neutrino mass has been determined from the decay using data collected with the OPAL detector from 1991 to 1995 in collisions at . A limit of 43.2 MeV at 95% CL is obtained using a two–dimensional method in the invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously published measurement using decays, a new combined limit of MeV (95% CL) is obtained. Received: 15 April 1998 / Published online: 12 August 1998