  The damping $\alpha$ of the spinwave resonances in 75 nm, 120 nm, and 200nm
-thick Permalloy films is measured via vector-network-analyzer
ferromagnetic-resonance (VNA-FMR) in the out-of-plane geometry. Inductive
coupling between the sample and the waveguide leads to an additional radiative
damping term. The radiative contribution to the over-all damping is determined
by measuring perpendicular standing spin waves (PSSWs) in the Permalloy films,
and the results are compared to a simple analytical model. The damping of the
PSSWs can be fully explained by three contributions to the damping: The
intrinsic damping, the eddy-current damping, and the radiative damping. No
other contributions were observed. Furthermore, a method to determine the
radiative damping in FMR measurements with a single resonance is suggested.
