Reaction time and reaction mechanisms of the medium-mass reaction system 84Kr+27Al at 8.5 MeV/u

Measurements of α-fragment coincidences in the reaction plane in the reaction 84Kr+27Al at 8.5 MeV/u show that the fully energy-damped symmetric fragments are dominantly produced in deeply inelastic collisions. From the measured α and proton multiplicities, the reaction time is deduced to be 8×10−21 seconds. The diffusion model calculations incorporating this reaction time reproduce well the measured fragment charge distributions.