Parity of the 2.10- and 1.08-MeV Levels inF18

Abstract

The linear polarization of the 2.10-MeV $\gamma$ ray, de-exciting the ${\mathrm{F}}^{18}$ 2.10-MeV level, has been measured. This, together with the mixing ratio recently determined by Gorodetzky et al. for this transition, fixes the parity of the 2.10-MeV level in ${\mathrm{F}}^{18}$ as odd. Since the 1.08-MeV level in ${\mathrm{F}}^{18}$ is known to have the same parity as the 2.10-MeV level, its parity is also fixed as odd. The structure of these two levels is discussed. In an Appendix, the results are reported of a separate experiment in which the mixing ratios of the 2.10 → 0-MeV and 2.10 → 0.94-MeV transitions were measured.