Induced and Spontaneous Fission of Nobelium Isotopes Using Collective Clusterization Approach

Abstract

The spontaneous fission (SF) has crucial importance in the identification and stability of numerous heavy and superheavy elements. In the recent years, various attempts have been made to investigate the dynamics of spontaneous fission from both the theoretical and experimental point of view. Here, in the present dissertation, I intend to analyze the properties of spontaneous fission decay of ‘Nobelium’ isotopes with mass varying from A=250 to 262. The performed cluster-decay model (PCM) based on quantum mechanical fragmentation theory (QMFT) is used to calculate the spontaneous fission half-lives (T1/2). The calculated SF half-lives find reasonable agreement with the recent experimental data. The behaviour of fragment mass distributions for each spontaneous fissioning nuclei is investigated, which changes from asymmetric to symmetric with increment in the mass of parent nucleus. The most probable decaying fragments are identified, and are found to lie in the neighbourhood of the magic shell closures. Moreover, the spontaneous fission dynamics is explored by studying the fragmentation potential (V), preformation probability (P0), barrier penetration probability (P) and total kinetic energy (TKE) corresponding to most preferred decaying fragments. In addition to this, a comparative analysis of SF and induced fission (fusion-fission) is carried out in terms of barrier characteristics and potential energy surfaces. Both the fission processes show similar behaviour with respect to fragment mass distribution. The ‘barrier modification’ effects have been explored and the requirement of barrier modification comes out to be relatively smaller for spontaneous fission as comparison to the induced fission process.