Investigation of nuclear structure at high spins in neutron deficient nuclei

Abstract

The main objective of the present thesis is to investigate the reaction mechanism in the population of neutron deficient nuclei and study different nuclear phenomena in the mass region A and#8764;100,120. The nuclei of interest 106Cd and 120Cs were populated in the fusion-evaporation reactions 16O + 94Zr at beam energy Elab = 77 MeV and 16O + 107Ag at Elab = 74 MeV, respectively. The beam was delivered by the 15UD Pelletron accelerator at Inter University Accelerator Centre (IUAC), New Delhi. The deexciting and#947;-radiations from the recoiling nuclei were collected using the Indian National Gamma Array consisting of 11 Compton-suppressed Clover detectors. The energy and efficiency calibration were performed using the 152Eu radioactive sources. A new VME based data acquisition system was used to record the data in single and coincidence mode. Lifetime measurements have been done for positive and negative parity bands in 106Cd nucleus using Doppler Shift Attenuation Method (DSAM) and the experimental results were studied in the framework of semiclassical particle-rotor model (SCM) calculations. The results indicates towards the anti-magnetic rotational (AMR) nature of these bands. Another negative parity band has been studied on the basis of theoretical model (SCM) calculations, which interprets it to be an AMR band. newlineThe experimental excitation function for the reaction 16O + 107Ag were determined in the energy range 71-80 MeV and compared with statistical models PACE4 and CASCADE predictions to yield the residual nuclei of interest at maximum cross-section. The residual nuclei were identified from their characteristic and#947;- transitions in the observed spectrum. Spin assignment have been done for the two bands of 120Cs on the basis of DCO ratio calculations. newline