Measurement of the cross section of the residues from the ~(11)B-induced reaction on ~(89)Y and ~(93)Nb: Production of ~(97)Ru and ~(101m)Rh

摘要

Background: The heavy-ion induced reactions on intermediate mass targets are complex in nature, even at the low energies. To understand those nuclear reaction phenomena in detail, more experimental studies are required in a wide range of energies. Purpose: Investigation of heavy-ion reactions by measuring production cross sections of the residues produced in the ~(11)B-induced reactions on ~(89)Y and ~(93)Nb at low energies, near and above the barrier, and to check the effectiveness of the different nuclear models to explain them. Further, aim is also to optimize the production parameters of neutron deficient medically relevant ~(97)Ru and ~(101m)Rh radioisotopes produced in those reactions, respectively. Method: The ~(11)B beam was allowed to impinge on ~(89)Yand ~(93)Nb foils supported by an aluminum (Al) catcher foil, arranged in a stack, in 27.5–58.7 and 30.6–62.3 MeV energy range, respectively. The off-line γ -ray spectrometry was carried out after the end of bombardment to measure the activity of the radionuclides produced in each foil and cross sections were calculated. Measured cross-sectional data were analyzed in terms of compound and precompound model calculations. Results: The measured cross sections of ~(97,95)Ru, ~(96,95,94)Tc, ~(93m)Mo, ~(90m)Y radionuclides produced in the ~(11)B+~(89)Y reaction, and ~(101,100,99)Pd, ~(101m,100,99m)Rh, ~(97)Ru produced in the ~(11)B+~(93)Nb reaction showed good agreement with the model calculations based on the Hauser-Feshbach formulation and exciton model. Unlike theoretical estimation, consistent production of ~(90m)Y was observed in the ~(11)B+~(89)Y reaction. Substantial pre-equilibrium contribution was noticed in the 3n reaction channel in both reactions. Conclusions: Theoretical estimations confirmed that major production yields are mostly contributed by the compound reaction process. Pre-equilibrium emissions contributed at the high energy tail of the 3n channel for both reactions. Moreover, an indirect signature of a direct reaction influence was also observed in the ~(90m)Y production.