Probing binary fragmentation dynamics of ^48 Ti + ^232 Th reaction at an excitation energy of 63.5 MeV

The present work concerns the study of fission dynamics of ^48 Ti+ ^232 Th reaction resulting in the superheavy composite system ^280 Cn _112 at an incident energy of 280 MeV. Mass distribution studies play an important role in understanding the fusion-fission mechanism involved in the heavy-ion induced nuclear reaction. The studies related to the superheavy nucleus ^280 Cn are limited till date and in order to achieve a better insight of the reaction dynamics, mass and total kinetic energy (TKE) distribution of the binary fragments populated in the reaction ^48 Ti+ ^232 Th has been measured at an excitation energy 63.5 MeV. Correlation between the mass and TKE and mass-angle distribution of the binary fragments have been investigated. The mass-energy distribution of the reaction fragments obtained from the analysis confirms the dominance of quasi-fission over fusion-fission. A sudden rise in the width of σ ^2_TKE (M) has been observed in the mass symmetric region. This has been interpreted in terms of the mixing of fusion-fission and quasi-fission events. A deviation from the Viola systematic is observed in the measured TKE of the fragments due to the presence of quasi-fission (QF) process. Theoretical results performed to understand the experimental results in the framework of the DNS model show that the peaks in the mass distribution of the binary products around the mass numbers A = 40–60 and A = 220–240 is related with the contribution of the DIC and quasi-fission products. The contribution of the quasi-fission products to the yield of the binary fragments with the mass numbers around A = 80–110 and A = 170–200 is dominant. The contribution of the symmetric quasi-fission products to the yield of the mass symmetric region is comparable with the yield of the fusion-fission products.