  The radio and X-ray observations of the Type Ic supernova SN 2002ap are
modeled. We find that inverse Compton cooling by photospheric photons explains
the observed steep radio spectrum, and also the X-ray flux observed by XMM.
Thermal emission from the shock is insufficient to explain the X-ray flux. The
radio emitting region expands with a velocity of, roughly, 70,000 km/s. From
the ratio of X-ray to radio emission we find that the energy densities of
magnetic fields and relativistic electrons are close to equipartion.
