Charge-Asymmetry Equilibration in the Reaction ofXe129,132,136withAu197near the Interaction Barrier

Neutron-proton population ratios for quasielastic and inelastic processes in the reactions of 761-MeV ${}_{}{}^{129}{}_{}{}^{}\mathrm{Xe}$, 769-MeV ${}_{}{}^{132}{}_{}{}^{}\mathrm{Xe}$, and 795-MeV ${}_{}{}^{136}{}_{}{}^{}\mathrm{Xe}$ ions with thick ${}_{}{}^{197}{}_{}{}^{}\mathrm{Au}$ targets were determined radiochemically. Completely relaxed $\frac{N}{Z}$ ratios are observed for damped collisions involving the transfer of $\Delta Z>~1$ charge units. The limiting condition $\Delta Z\approx 1$ corresponds to a characteristic time of the order of ${10}^{-22\mathrm{}}$ sec which indicates the absence of dissipative forces in the equilibration of the charge-asymmetry mode.