Investigation of quadrupole deformation of nucleus and its surface dynamic vibrations

Abstract

The new complete database - Chart of nuclear quadrupole deformations - was developed using various sources of related information. Using this Chart the system comparative analysis of quadrupole deformation parame- ters β2 obtained by two different methods was carried out for many nuclei. The clear systematical disagreements of β2 parameters obtained from nuclear quadrupole moments Q (Q-type data) and from reduced transition probability B(E2) ↑ for 0 + → + transitions (B-type data) were revealed. It was found out that all nuclides investigated are clearly separated into two groups. For all isotopes of group 1 nuclei good agreement was observed for data of both types. For all isotopes of group 2 nuclei B-type β2 data values are systematically (in many cases significantly) larger than Q-type ones. In cases of only few exceptions disagreement for some isotopes are combined with agreements for others. It was shown that two types data difference could be explained in the frame of assumption about the not negligible role of dynamic vibrations of nucleus surface, by other words, about dependence of quadrupole deformation parameter β2 values on surface vibrations of nucleus in ground state. From this point of view Q-type β2 values do not take into account nucleus surface vibration, but B-type β2 values do that. Therefore B-type data reflect not only static nuclear deformation (deviation of nucleus shape from spherical), but dynamic deformation also.