Properties of fission fragments forZ=112−116superheavy nuclei

Abstract

The dynamical cluster decay model (DCM) is applied to understand the dynamics of $^{48}\mathrm{Ca}+^{238}\mathrm{U},^{244}\mathrm{Pu},^{248}\mathrm{Cm}$ reactions at comparable excitation energies across the barrier. To understand the capture stage of $^{286}112^{*},\phantom{\rule{0.16em}{0ex}}^{292}114^{*}$, and $^{296}116^{*}$ nuclei, the compound nucleus formation probability is calculated. The indication of ${P}_{CN}l1$ in the DCM framework demonstrates the fact that some competing process such as quasifission may occur at the capture stage of the $^{48}\mathrm{Ca}$ induced reactions. To understand this further, the comparative decay analysis of $^{286}112^{*},\phantom{\rule{0.16em}{0ex}}^{292}114^{*}$ and $^{296}116^{*}$, nuclei is carried out using ${\ensuremath{\beta}}_{2i}$ deformations within hot optimum orientation criteria, and the calculated fission cross sections find nice agreement with available data. The fission mass distribution shows a double humped structure where a symmetric peak observed around the Sn region appears to find its genesis in a symmetric quasifission component. On the other hand, the emergence of peaks around Pb in the decay of $Z=112$, 114, and 116 nuclei signify the possible presence of asymmetric quasifission. Higher and broader asymmetric quasifission peaks are observed for $^{296}116^{*}$ and $^{292}114^{*}$ nuclei as compared to $^{286}112^{*}$ nucleus. Beside this, the total kinetic energy (TKE) distribution of the decay fragments is also explored by using different proximity potentials, such as Prox-77, Prox-88, and Prox-00. Prox-88 seems to perform better and the calculated TKE values find relatively better comparison at lower angular momentum states. The possible role of different radii of the decaying nuclei is also exercised to understand the $\overline{\mathrm{TKE}}$ dynamics of $^{48}\mathrm{Ca}+^{238}\mathrm{U},^{244}\mathrm{Pu},^{248}\mathrm{Cm}$ reactions.