Investigation of decay mechanisms and associated aspects of exotic Nobeliumisotopes using the Skyrme energy density formalism

Abstract

Persistent theoretical and experimental attempts have been made to investigate the heavy ion induced reactions and their subsequent decay mechanisms in superheavy mass region. In addition, the region of transfermium elements is itself of great interest because of the neutron / proton shell effects. Here, we aim to study the subsequent decay mechanisms of two isotopes of Z = 102 nucleus, i.e. 248No and 250No. The dynamical cluster-decay model (DCM) based on Quantum Mechanical Fragmen- tation Theory (QMFT), is employed to conduct a comprehensive analysis of compound nucleus (CN) and non-compound nucleus (nCN) mechanisms such as fusion-fission (ff), Quasi fission (QF) and fast fission (FF), the role of centre of mass energy (Ec.m.) and angular momentum (ℓ) for 248No and 250No isotopes. The nuclear interaction potential is obtained using the Skyrme energy density formalism (SEDF) in the domain of GSkI force parameters. The probability of compound nucleus formation (PCN ) is determined using a function that depends on the centre of mass energy. The lifetimes for the fusion-fission (ff) quasi fission (QF) channels are explored. Here, CN and nCN decay mechanisms for two isotopes of Z = 102 nobelium are studied over the wide range of centre-of-mass (Ec.m.) by including the quadrupole deformation (β2) and optimum orientations (θopt.) of decaying fragments. The fragmentation potential, preformation probability, neck length parameter and reaction cross-sections are explored. Further, the calcula- tions are done for PCN in order to identify the decay modes of 248No and 250No isotopes. The fusion-fission lifetimes and quasi fission lifetimes are compared with the dinuclear system (DNS) approach. The most probable fragments such as 122Sn and 128T e are observed near to the magic shell closure Z = 50 and N = 82. The ff and qf lifetime decreases with increase in the excitation energy.