  We demonstrate the role played by the fullerene shell in the photoionization
and vacancy decay of endohedral atoms A@C60. It is shown, partly in the frame
of a rather simple model that describes the fullerene shell, partly using only
the assumption on the smallness of the atom A in comparison to the size of C60
that it affects photoionization and the vacancy decay of A@C60 profoundly.
Namely, it leads to a number of new resonances in photoionization cross-section
and other photoionization characteristics as well as strong modifications of
the vacancy decay probabilities and opening of new decay channels. We discuss
the problem of photon propagation through the C60 shell and conclude that at
any considered frequency, up to about 60 eV, the C60 enhances the incoming
radiation. This shows non-metallic dielectric behavior of the 240 collectivized
electrons in C60. We discuss also the C60 effects upon the fast electron
inelastic scattering. The results obtained are valid qualitatively also for
other than C60, e.g. for C70 or C76.
