We have studied the evolution towards mass equilibration in ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$${+}^{16}$O orbiting interactions. ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ beams of energies between 75 and 115 MeV were used to bombard targets of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$. Targetlike particles were detected at forward angles to determine the yields from orbiting interactions. The ratio of the orbiting yields of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ exit channels rises continuously with energy from values below unity to above. The data are interpreted as demonstrating a strong entrance channel dependence at low energies, and an evolution towards mass equilibration with increasing energy.

• Received 18 December 1991

DOI:https://doi.org/10.1103/PhysRevC.46.1946