  Spontaneous violation of R parity can induce rare single photon decays of the
$Z^0$ involving the emission of (nearly) massless pseudoscalar Goldstone
bosons, majorons, as well as massive CP even or CP odd spin zero bosons that
arise in the electroweak breaking sector of these models. We show that the
majoron emitting decays can have a sizeable branching ratio of $10^{-5}$ or so,
without conflicting any experimental observation from neutrino physics or
particle searches. These decays may lead to interesting structures for the
single photon spectrum involving either mono chromatic photons as well as
continuous spectra that grow with energy. They would easily account for an
excess of single photon events at high energies recently hinted at by the OPAL
collaboration.
