Electromagnetic Polarizabilities of Nucleons bound in ${}^{40}$Ca, ${}^{16}$O and ${}^4$He

Differential cross sections for elastic scattering of photons have been measured for ${}^{40}$Ca at energies of 58 and 74 MeV and for ${}^{16}$O and ${}^4$He at 61 MeV, in the angular range from 45${}^o$ to 150${}^o$. Evidence is obtained that there are no significant in-medium modifications of the electromagnetic polarizabilities except for those originating from meson exchange currents.