  Pump-probe experiments and polarizing microscopy are applied to examine
temperature and heat flow in metallic magnetic superlattices on glass
substrates. A model of heat diffusion in thin layers for cylindrical symmetry,
equivalent to the Green's function method, gives a good description of the
results. The frequency dependence of temperature modulation shows that a glass
layer should be added to the sample structure. The demagnetization patterns are
reproduced with a Green's function that includes an interface conductance.
