LIGHT-PARTICLE EMISSION IN THE REACTION SM-144(S-32, FISSION) AT E(LAB)=838 MEV

Energy spectra of light charged particles have been measured in coinci dence with fissionlike fragments using the 4pi charged-particle detect or AMPHORA. Preequilibrium, prescission, and postscission components o f emitted protons, deuterons, and alphas have been extracted from the energy spectra using a multiple source fit procedure. Including previo usly measured exclusive neutrons, a complete data set for light partic le emission from the system 144Sm + S-32(26 A MeV) is now available. M ass and excitation energy of an equilibrated composite system has been defined by application of the massive transfer model using multiplici ties and apparent temperatures of the preequilibrium components. The r esults have been compared to statistical model computations. A fair ov erall agreement is observed for different parametrizations of the Ferm i-gas level-density parameter with indications for a decrease of the l evel density parameter with increasing nuclear temperature. The correl ations between slope parameter, prescission, and total particle multip licity turned out to be a sensitive probe for the level density parame ter. In the energy spectra of alpha particles a low-energy component h as been observed with strong focusing into directions perpendicular to the fission axis.