Excited state production has been measured for ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$, ${}_{}{}^7{}_{}{}^{}\mathrm{Be}$, and ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$ fragments emitted in the ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$${+}^{12}$C reaction at E/A=8, 10, and 12 MeV. The use of reverse kinematics and a system with low rotational kinetic energy permitted a more direct test of the excited state method for temperature determination than had previously been possible. The results show that the population of excited states reflects the temperature expected from Fermi gas calculations at the appropriate excitation energy for the compound nucleus and is consistent with the temperature determined from the slope of the fragment spectra.

• Received 21 August 1989

DOI:https://doi.org/10.1103/PhysRevC.41.2406