Proton and alpha evaporation spectra in low energy ~(12)C and ~(16)O induced reactions

摘要

Proton and alpha particle spectra have been measured in the ~(12)C+~(93)Nb and ~(12)C+~(58)Ni reactions at E(~(12)C) = 40 and 50 MeV and in the ~(16)O+~(93)Nb reaction at E(~(16)O) = 75 MeV. The spectra are compared with the statistical model calculations. The shapes of the calculated spectra are in agreement with experimental data except for the alpha spectrum in the ~(12)C+~(93)Nb reaction at 40 MeV. The observed evaporation bump is at ～2 MeV lower energy compared to the calculated one. This discrepancy could imply alpha particle emission from a deformed configuration before compound nucleus formation at this near Coulomb barrier beam energy.