The spin-flip probability has been measured using the Schmidt particle-γ coincidence technique for the reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ leading to the first excited state of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ at energies $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}$=17.28 and 26.88 MeV. Both forward and backward angles in the center of mass system were studied, the latter only at the lower bombarding energy. The particle-γ angular correlation has also been measured in the reaction plane. The data have been analyzed by treating the elements of the density matrix of the final $2^{+}$ state as unknown parameters using a least squares fitting procedure. The results of this analysis have been compared with reaction model calculations, and suggest that the observed spin-flip probability can be accounted for without the necessity of introducing a phenomenological spin-dependent component into the nucleus-nucleus optical potential.

• Received 19 February 1985

DOI:https://doi.org/10.1103/PhysRevC.32.452