The explanation of anomalous mean free paths, observed in relativistic heavy-ion collisions in emulsions, by the excitation of molecular configurations in projectile fragments, is discussed. The γ-decay half-life of molecular states in ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ and ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ are calculated in a microscopic cluster model and compared with the inferred mean lifetimes of anomalous projectile fragments. While the half-life of the ${}_{}{}^{16}{}_{}{}^{}$O${+\mathrm{}}^{16}$O molecular states might be compatible with this explanation, an identification as anomalous projectile fragments can be ruled out for the ${}_{}{}^{12}{}_{}{}^{}$C${+\mathrm{}}^{12}$C molecular states. It is argued that because of nuclear structure effects, molecular configurations in neighboring nuclei have lifetimes similar to the ${}_{}{}^{12}{}_{}{}^{}$C${+\mathrm{}}^{12}$C molecular states.

• Received 25 February 1985

DOI:https://doi.org/10.1103/PhysRevC.32.163