Dynamical effects in the decay of a compound nucleus

Abstract

We have measured the $\ensuremath{\alpha}$-particle spectra at different laboratory angles from the fusion reaction ${}^{16}\mathrm{O}{+}^{54}\mathrm{Fe}$ at 110 MeV. The results are compared with the ${}^{28}\mathrm{Si}{+}^{27}\mathrm{Al}$ symmetric system. In the case of the asymmetric ${}^{16}\mathrm{O}{+}^{54}\mathrm{Fe}$ system $\ensuremath{\alpha}$ spectra are consistent with the predictions of the statistical model calculations but in the case of the symmetric ${}^{28}\mathrm{Si}{+}^{27}\mathrm{Al}$ system, experimental spectra deviate at higher as well as at lower energies from the statistical model calculations. The results are also compared with a less asymmetric ${}^{28}\mathrm{Si}{+}^{51}\mathrm{V}$ system. There is a systematic change in the formation time of the compound nucleus as we move from the asymmetric to the symmetric systems. The dynamical trajectory model calculations have been done to understand the possible entrance channel effects on the formation and the decay of the compound nucleus.