The dynamical cluster-decay model (DCM) of Gupta and Collaborators has been used to study the decay of various Pt-isotopes 176,182,188,196 Pt * formed in 64 Ni+ 112,118,124 Sn and 132 Sn+ 64 Ni reactions. The evaporation residue (ER) and fission cross-sections (σ ER and σ fiss ) are calculated in reference to available experimental data at near-and sub-barrier energies. The calculated σ ER show excellent agreement with experimental data at all incident center-ofmass (c.m.) energies, with the characteristics of emitted light particles (LPs) showing a change with the increase of the iso-spin N/Z ratio of compound nucleus (CN). The only parameter of DCM, the neck-length parameter, for 196 Pt * becomes much smaller, compared to other 176,182,188 Pt * isotopes, and more so at higher c.m. energies, possibly due to additional eight neutrons of the radioactive 132 Sn nucleus. Another interesting result of the DCM calculation is that, similar to other well-known 64 Ni+ 58,64 Ni and 64 Ni+ 100 Mo) reactions, an inbuilt 'barrier lowering' effect is also shown operating for σ ER as well as σ fiss at sub-barrier energies in these reactions. Furthermore, the calculated σ fiss shows a significant contribution of quasifission (σ qf ) at the highest one or two energies, and, due to the deformation and orientation effects of fission fragments, shows a change of the mass distributions from a predominantly symmetric to a predominantly asymmetric one with the increase in the N/Z ratio of CN. This change in fission mass distributions provides the possibility of fine-/sub-structure in fission products of Pt * isotopes.

The decay of 215 Fr * nucleus, formed in 11 B+ 204 Pb and 18 O+ 197 Au reactions, is studied by using the dynamical cluster-decay model (DCM) with effects of deformations and orientations of nuclei included in it. The observed decay is mainly via fusion-fission, with data collected for both the fission excitation functions and fission fragment anisotropies. The chosen reaction channels have entrance channel mass asymmetries lying on either side of the Bussinaro-Gallone critical asymmetry parameter. In agreement with experimental data and conclusions based on the statistical code PACE2, for fission excitation functions, our DCM calculations with max value used in accordance with the sticking moment of inertia also show no contribution of the quasi-fission component in fission cross-sections for both the reaction channels, measured at incident center-of-mass energy spread on either side of the Coulomb barrier. Due to deformation and orientation of nuclei, the fission mass distribution is asymmetric, and nearly independent of the entrance channel. Interestingly, for a best fit to data on fission cross-sections, an in-built 'barrier lowering' seems operative at sub-barrier energies for both the reactions under study. Also, the fission fragment anisotropies, calculated on DCM for the first time, using non-sticking moment of inertia are found consistent with experimental data for both the reaction channels, confirming beyond doubt the entrance channel's independence of the decay of 215 Fr * .

The dynamical cluster-decay model (DCM) is used to study the odd-mass nuclear systems 213 Fr * (with N = 126) and 217 Fr * (with N = 130) formed in 19 F + 194,198 Pt reactions. The measured anomaly in fission anisotropy for 213 Fr * in this reaction is said to be due to either the possible role of the magic N = 126 shell of the compound nucleus (CN) or the presence of a noncompound nucleus component, such as quasifission, in the fission cross section. Our calculations are made within the DCM for the fragments having quadrupole (β 2 ) deformations with orientations of compact, hot configurations, compared with spherical as well as β 2 -β 4 deformed considerations. For quadrupole deformed fragments (with "optimal" orientations), the calculated fission cross-sections (as well as the evaporation residue cross-sections) match the data nearly exactly, without invoking a significant contribution from quasifission. The calculated fission mass distribution for the two systems is quite similar for either of the spherical, β 2 -alone deformed, and β 2 -β 4 deformed choices of fragments. A small hump or shoulder is seen in fragment preformation yields for the deformed case (β 2 or β 2 -β 4 ) in both the systems due to a deformed closed shell around Z 2 = 36 and a spherical magic shell around Z 1 = 50, which for 213 Fr * (N = 126) decay is somewhat more pronounced as compared to 217 Fr * (N = 130). Note that the magic shell of the CN proton/neutron number plays no role in DCM.

The decay of the hot and rotating compound nucleus 241 Pu * formed in the reaction 9 Be + 232 Th around the Coulomb barrier (≈42.16 MeV), at energies ranging from 37 to 48 MeV, is studied using the dynamical cluster-decay model (DCM) with the effects of static and dynamic deformations included. With the inclusion of dynamical deformations both the preformation probability P 0 and the tunneling probability P , and hence the cross sections, change considerably. The only parameter of the model, namely, the neck-length parameter, varies smoothly with excitation energy or temperature of the system both at above-and below-barrier energies, whose value depends strongly on the limiting angular momentum, which in turn depends on the sticking and nonsticking moments of inertia. The relative effect of static and dynamic deformations on the neck-length parameter R is also studied which indicates the reaction time scale for both static and dynamic choices of deformation. In addition, the exclusive role of angular momentum and "barrier modification" effects at sub-barrier energies are also addressed. Although calculated anisotropies are consistent with the results of Appannababu et al. [Phys. Rev. C 83, 067601 (2011)], no significant contribution of a noncompound nucleus in the form of incomplete fusion is seen on the basis of DCM calculations.

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