Absolute differential cross sections were measured at 125° with $6\le E_d\le 11$ MeV for the ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}(d,\alpha ){}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ reaction leading to the 1.70-, 2.10-, 2.52-, 3.06-, 3.13-, and 3.36-MeV states of ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ and at 45° with $5\le E_d\le 13$ MeV for the 2.52-, 3.06-, and 3.13-MeV states. Angular distributions were measured at 6.66, 7.29, 7.93, and 12.95 MeV for the 2.52-, 3.06-, 3.13-, 3.36-, and 4.12-MeV states and at the three lower energies for the 2.10-MeV state. Uncertainties for the isolated states are 3.4%; for the 3.13-MeV state, 5.7%; and for the 3.06-MeV state, 5.7 to 20.2%. The ratio of the cross section for the forbidden reaction to the 3.06, $2^{+}$, $T=1\mathrm{}$ state to the cross sections for the other five ($T=0\mathrm{}$) states ranges from 6 to 40% with an average of 21%. The reaction appears to proceed through the compound nucleus. The large violation is discussed in terms of mixing in the compound nucleus and final-state impurity.

• Received 27 November 1972

DOI:https://doi.org/10.1103/PhysRevC.8.230