By the simultaneous measurement of the magnetic rigidity of the ${\alpha }_0^{++}$ and ${\alpha }_2^{+}$ groups from the ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}(p,\alpha ){}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ reaction, using a double-focusing spectrometer, the excitation energy of the second excited state of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ is found to be 7654.2± 1.6 keV.

• Received 30 June 1972

DOI:https://doi.org/10.1103/PhysRevC.7.489