Analysis of mass-separated evaporation residues formed in 32S + 70,68Zn fusion reactions: the special case of 97,95Ru

Abstract

Background: The experimental knowledge of nuclear reaction data and decay properties plays a vital role in searching for novel and exotic radioisotopes, prompting us to widen the experimental study of heavy-ion induced reactions. Purpose: The aim is to study the production of mass separated (i.e., separation of different masses of residues, where each mass group consists of isobaric nuclei) evaporation residues (ERs) populated in 32S + 70Zn and 32S + 68Zn reactions within 115–135 and 130–150 MeV incident energy ranges, respectively, and optimization of masses 97 and 95 u that consist of 97Pd, 97Rh, 97Ru, and 95Pd, 95Rh, 95Ru, 95Tc isobaric residues, respectively. Method: Mass separation of ERs has been achieved at the focal plane of the Heavy Ion Reaction Analyser (HIRA) at the 15 UD Pelletron facility, IUAC, India. The residues were detected at the focal plane of HIRA using a multiwire proportional counter (MWPC). Results: Competing production of masses 97 and 95 u through the fusion of 32S ions with 70Zn and 68Zn, respectively, have been observed in comparison to their neighboring masses within the measured energy range. The maximum cumulative production of 97Ru has been found to be ≈99 ± 9.9 Bq/h pnA(mg/cm2) at 125 MeV, while for 95Ru it is ≈69 ± 6.9 Bq/h pnA(mg/cm2) at 135 MeV. Comparisons of experimental results with the theoretical calculations indicate that the residues are mainly populated through the compound reaction mechanism. Conclusions: As anticipated from theory, significant yields of 97Ru and 95Ru in reactions 32S + 70Zn and 32S + 68Zn have been achieved via cumulative production of different isobars of mass 97 and 95 u, respectively. Cumulative yield of 97Ru has been found to be equivalent, i.e., the same order of magnitude [viz., ≈107 nuclei/h pnA(mg/cm2)], compared to its independent production through 11B and 7 Li projectile induced reactions.