Weak effects in e$^{+}$e$^{-}$ production of superheavy flavours

The authors investigate the experimental possibilities of detecting new superheavy flavours in e/sup +/e/sup -/ annihilation when considering both electromagnetic and weak contributions and taking radiative corrections into account. For masses of the order of m/sub w / or higher, the production of bound vector states is dominated by weak current effects, with cross sections strongly peaked at the mass of the Z/sup 0/. For continuum thresholds, the spherocity behaviour is also considerably distorted by the Z/sup 0/ peak and its radiative tail. A direct quarkonium search seems to be feasible only up to the gauge boson mass region, whereas the detection of enhancements in the mean spherocity associated with either qq bound states or continuum thresholds also allows the detection of superheavy flavours above the gauge boson mass region. (42 refs).