Direct Experimental Evidence of Nonequilibrium Energy Sharing in Dissipative Collisions

Primary and secondary masses of heavy reaction products have been deduced from kinematics and energy–time-of-flight measurements, respectively, for the direct and reverse collisions of ${}^{100}\mathrm{Mo}$ with ${}^{120}\mathrm{Sn}$ at $14.1A$MeV. Direct experimental evidence of the correlation of energy sharing with net mass transfer and model-independent results on the evolution of the average excitation from equal-energy to equal-temperature partition are presented.