  We report results of a search for the rare radiative decay B0 -> D*0 gamma.
Using 9.7 million BB meson pairs collected with the CLEO detector at the
Cornell Electron Storage Ring, we limit Br(B0->D*0 gamma) < 5.0 * 10^-5 at 90%
CL. This provides evidence that anomalous enhancement is absent in W-exchange
processes and that weak radiative B decays are dominated by the short-distance
b -> s gamma mechanism in the Standard Model.

High Energy Physics - Experiment;High Energy Physics - Phenomenology