Fragmentation products with nonstatistical excited-state populations

Abstract

Relative populations of particle-unbound states were measured for ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$ nuclei emitted behind the grazing angle for the ${}_{}{}^{14}{}_{}{}^{}$N${+}^{\mathrm{nat}}$Ag reaction at E/A=35 MeV. The populations of states decaying by proton and α-particle emission are inconsistent with purely statistical distributions, indicating that the intrinsic degrees of freedom of the fragmenting system may not be fully equilibrated at the instant the fragment separates from the rest of the system.