Angular distribution ofO−from dissociative electron attachment to NO

The electron energy dependence of the angular distribution of ${\mathrm{O}}^{-}$ produced by dissociative electron attachment to NO has been measured in the energy range 8.0-11.0 eV. The distributions are observed to be anisotropic and of a form that is nearly ${sin}^2\theta$ at all energies. Deviations from a ${sin}^2\theta$ dependence are discussed in terms of the relative contributions of different partial waves to the differential cross section. The results indicate that the final repulsive negative-ion resonances involved must be either $\Sigma$ or $\Delta$ states.