Non-equilibrium neutron emission in ?-induced reactions on124Sn

Abstract

Neutron time-of-flight spectra were measured in coincidence with y-rays characteristic for the xn (x=2, 3, 4, 5) fusion-like products in reactions of 35-57 MeV a-particles with 124Sn. Additional information was obtained from excitation function and 7-multiplicity measurements. The neutron energy spectra for a specific x n channel at high bombarding energies clearly show the presence of nonequilibrium neutron emission. The spectra are parameterized in terms of emission from a slow equilibrated and a fast moving source. The fast moving source has a velocity close to the beam velocity indicating a close relationship between the movement of the projectile and the neutron emission.