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The decay of56 N i * , formed in 32 S + 24 M g reaction at the incident energies Ecm=51.6 and 60.5 MeV, is calculated as a cluster decay process within the Preformed Cluster-decay Model (PCM) of Gupta et al. re-formulated for hot compound systems. Interesting enough, the cluster decay process is shown to contain the complete structure of both the measured fragment cross sections and total kinetic energies (TKEs). The observed deformed shapes of the exit channel fragments are simulated by introducing the neck-length parameter at the scission configuration, which nearly coincides the 56 N i saddle configuration. This is the only parameter of the model, which though is also defined in terms of the binding energy of the hot compound system and the ground-state binding energies of the various emitted fragments. For the temperature effects included in shell corrections only, the normalized α-nucleus s-wave cross sections calculated for nuclear shapes with outgoing fragments separated within nuclear proximity limit (here ∼0.3 fm) can be compared with the experimental data, and the TKEs are found to be in reasonably good agreement with experiments for the angular momentum effects added in the sticking limit for the moment of inertia. The incident energy effects are also shown in predicting different separation distances and angular momentum values for the best fit. Also, some light particle production (other than the evaporation residue, not treated here) is predicted at these energies and, interestingly, 4 He, which belongs to evaporation residue, is found missing as a dynamical cluster-decay fragment. Similar results are obtained for temperature effects included in all the terms of the potential energy. The non-α fragments are now equally important and hence present a more realistic situation with respect to experiments. [2][3][4][5][6][7][8]). At such incident energies, the incident flux is found to get trapped by the formation of a compound nucleus (CN), which is in addition to a significant large-angle elastic scattering cross section. For lighter masses (A CN < 44), such a compound nucleus decays subsequently by the emission of mainly light particles (n, p, α) and γ-rays; i.e. with very small component of heavy fragment (A > 4) emission. An experimental measure of this so-called particle evaporation residue yield is the CN fusion cross section. For somewhat heavier systems, like 48 Cr and 56 N i, a significant decay strength to A > 4 fragments, the mass-asymmetric channels, is also observed which could apparently not arise from a direct reaction mechanism because of the large mass-asymmetry differences between the entrance and exit channels. The measured angular distributions and energy spectra are consistent with fission-like decays of the respective compound systems. PACSFor the 32 S + 24 M g → 56 N i * reaction, in one of the experiments, the mass spectra for A=12 to 28 fragments and the total kinetic energy (TKE) for only the most favoured (enhanced yields) α-nucleus fragments are measured at the energies E ...

The decay of 56 Ni*, formed in 32 Sϩ 24 Mg reaction at the incident energies E c.m. ϭ51.6 and 60.5 MeV ͑where c.m. is the center of mass͒, is calculated as a cluster decay process within the preformed cluster-decay model of Gupta et al. ͓Phys. Rev. C 65, 024601 ͑2002͔͒ reformulated for hot compound systems. Interestingly enough, the cluster decay process is shown to contain the complete structure of both the measured fragment cross sections and total kinetic energies ͑TKEs͒. The observed deformed shapes of the exit channel fragments are simulated by introducing the neck-length parameter at the scission configuration, which nearly coincides with the 56 Ni saddle configuration. This is the only parameter of the model, which, though, is also defined in terms of the binding energy of the hot compound system and the ground-state binding energies of the various emitted fragments. For the temperature effects included in shell corrections only, the normalized ␣-nucleus s-wave cross sections calculated for nuclear shapes with outgoing fragments separated within nuclear proximity limit ͑here ϳ0.3 fm) can be compared with the experimental data, and the TKEs are found to be in reasonably good agreement with experiments for the angular momentum effects added in the sticking limit for the moment of inertia. The incident energy effects are also shown in predicting different separation distances and angular momentum values for the best fit. Also, some light particle production ͑other than the evaporation residue, not treated here͒ is predicted at these energies and, interestingly, 4 He, which belongs to evaporation residue, is found missing as a dynamical cluster-decay fragment. Similar results are obtained for temperature effects included in all the terms of the potential energy. The non-␣ fragments are now equally important, and hence present a more realistic situation with respect to experiments.

Using the quantum molecular dynamics model, we aim to investigate the emission of light complex particles, and degree of stopping reached in heavy-ion collisions. We took incident energies between 50 and 1000 MeV/nucleon. In addition, central and peripheral collisions and different masses are also considered. We observe that the light complex particles act in almost similar manner as anisotropic ratio. In other words, multiplicity of light complex particles is an indicator of global stopping in heavy-ion collisions. We see that maximum light complex particles and stopping is obtained for heavier masses in central collisions.

Within the framework of Skyrme energy density formalism, we investigate the role of surface corrections on the fusion of colliding nuclei. For this, the coefficient of surface correction was varied between 1/36 and 4/36, and its impact was studied on about 180 reactions. Our detailed investigations indicate a linear relationship between the fusion barrier heights and strength of the surface corrections. Our analysis of the fusion barriers advocate the strength of surface correction of 1/36.