Incomplete fusion studies near Coulomb barrier: a modified sum rule model

Abstract

Abstract. The excitation functions of the evaporation residues, produced via complete fusion and incomplete fusion reactions of 11 B + 122 Sn, were measured for the projectile energy of around 6 MeV/A by the off-line gamma spectrometry. The cross sections have been compared with the statistical model code Projected Angular Momentum Coupled Evaporation (PACE4). The original sum rule model underestimated the ICF cross sections. We therefore made modification in the model mainly to incorporate the energy dependence in the definition of critical angular momentum. Using this modified sum rule model, we found a significant improvement in the results.

Towards Understanding Incomplete Fusion Reactions at Low Beam Energies: Modified Sum Rule Model

“…Earlier works in the literature demonstrated the success of SRM in reproducing the cross-section for ICF channels in 12 C+ 160 Gd [49] and 14 N+ 159 Tb [8] reactions at high beam energies. However, it failed at low beam energies [33,34,37,38], as in our present work.…”

“…We determined the absolute intensity of the characteristic gamma transitions of daughter nuclei by finding the photopeak area with the gf3 program of the RADWARE package [40]. The data were analyzed using the prescription in our earlier report [37]. In that report, we also described our method of double-channel analysis for the cases of two parents β-decaying to the same daughter nuclei, e.g., the decays of 128 Cs and 128 I to 128 Xe.…”

“…2. In our earlier work [37], we proposed a model in an attempt to modify SRM [8]. In the present work, we have further refined the model and named it MSRM2, keeping the basic formalism of the original SRM intact.…”

“…This has been found to be consistent with the multiplicity measurements [4,8,20] at high beam energies. In several studies [19,[33][34][35][36][37][38] at beam energies just above the Coulomb barrier, the maximum entrance channel's angular momentum ( max ) is quite low. On the other hand, cr , that is independent of beam energy in the original SRM, remains unaffected.…”