Emission times for energy selected H1,2,3 ejectiles from central collisions: 1360 MeV Ar40+Ag

For central collisions of 1360 MeV Ar40 + Ag we report correlations in relative momentum and in velocity difference for H1,2,3 ejectiles at 32° and 68°. Comparison to trajectory calculations gives a measure of the mean emission times, and, for unlike pairs, the average emission orders. There is a strong variation of the average emission times as a function of ejectile energy that is very similar for each H isotope; they change from 1000 fm/c for 10 MeV in the c.m. to 50 fm/c for 30 MeV. This indicates a broad spectrum of emission sources and associated characteristics. The longer times suggest evaporative emission from thermalized systems for H1,2,3 of energies 10 MeV (i.e., those near the emission barrier). The shorter times, along with the observed energy spectra, suggest extensive prethermalization or direct emission from the central collision zone for H1,2,3 ejectiles of much higher energy.