Flavor changing radiative $D$ meson decays

Flavor changing radiative decays of the bottom quark provide tests of the Standard Model and powerful constraints on new physics. A better understanding of the long distance contributions to these processes may help reduce theoretical uncertainties on the predicted rates. Flavor changing radiative $D$~meson decays are dominated by long distance contributions due to a vector meson coupling to a photon and are suitable for confronting predictions of nonperturbative mechanisms. We present a measurement of the branching fraction of $D^{0} \rightarrow \phi \gamma$ in $281 \pb^{-1}$ of data collected by the CLEO-c detector at the Cornell Electron Storage Ring. We also present a measurement of the branching fraction, $D^{0} \rightarrow \phi \pi^{0}$, a significant background to the radiative decay.