Some problems in collective nuclear structure and review of the nuclear models

The work is limited to the study of even-even nuclei in the medium mass region of rare earths i.e. A = 150 to 200. Only the collective nuclear structure, as exhibited in the low energy rotation-vibration bands, has been studied. Basically, the collective motion of the nucleus is dealt with in the Unified Collective Model of Bohr-Motteleson which is phenomenological. The microscopic theory of Kumar and Baranger (1965) in shell model approach provides further insight. The more recent phenomenological Interacting Boson Model (IBM) of Arima and Iachello (1984) using the group algebric techniques provides an alternative treatment. (author)