Separation of surface- and volume-vibrations in quadrupole-deformed nuclei and consequences on isotope shifts
Starting from the complete hamiltonian for a system ofN nucleons, the problem of separating volume and surface vibrations inpermanently deformed nuclei is investigated. The required “volume” variable which allows this separation turns out to be the mean square distance of a nucleon with reference to the center of mass. Our investigation confirms the concept ofpure surface vibrations, as is used in the rotationvibration model ofFässler andGreiner, and leads to a theoretical argument in favour ofFradkin's idea of “compressibility under deformation” forced upon him by experimental evidence in calculating isotope shifts in deformed nuclei.