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Angular and energy distributions are reported for 4 He in correlation with 1,2,3 H and 4 He in the reaction 337 MeV 40 Ar+ nat Ag. Comparisons are made to a statistical model that includes emitter. Energy spectra important barrier reductions compared to those for cold nuclei, ≈25%, 12%, 8% and 0 for 1 H, 4 He, 2 H and 3 H respectively. Emitter deformation alone cannot give an explanation. A transitory nuclear stratosphere is suggested with proton emission favored from its fringes of lowest density.

We have investigated the emission of 4 He in coincidence with mass-selected fragments from fission for 334 MeV 40 Ar + 238 U. Upper-limit multiplicities are assigned for fragment evaporation and composite-nucleus evaporation, but additional mechanisms are also required. A new low-energy component is found at backward angles; it is sensitive to the fragment masses but does not reflect their full kinematic shifts. Thus it must be due to near-scission emission (prior to full fragment acceleration).