Probing the fission dynamics of $^{\mathrm{\mathbf{192,202}}}Po compound nuclei using neutron multiplicity measurements

The dominant reaction mechanism for the nuclear reactions induced between heavy ions is fusion-fission (FF) as well as non-equilibrium process called quasi-fission (QF). In order to disentangle the FF and QF processes, we have measured the neutron multiplicity for $^{\mathrm{48}}$Ti $+^{\mathrm{144,154}}$Sm $\to^{\mathrm{192,202}}$Po compound nuclei. For the system $^{\mathrm{18}}$O $+^{\mathrm{192}}$Os $\to ^{\mathrm{210}}$Po, experimental data exists for neutron multiplicity. For systems with heavier projectile, sizable contribution from QF process is expected. We have performed a consistent analysis of Po (N$=$108 to 126) nuclei to study the role of shell effects. This experiment was performed using National Array of Neutron Detectors (NAND) facility at IUAC, New Delhi. The pre- and post-scission components of neutron multiplicities are obtained from the measured neutron energy spectra by using a multiple source least-square fitting procedure, using the Watt expression. Statistical model calculations were performed for these systems using Bohr Wheeler and Kramer's formalism [1]. [1] R. Mahajan \textit{et al.,} Phy. Rev. C 98, 034601 (2018).