Elastic and Inelastic Scattering of Alpha Particles byN14

The absolute differential cross section for the elastic and inelastic scattering of 19.2-Mev alpha particles by ${\mathrm{N}}^{14}$ was measured as a function of the scattering angle. The forward part of the ground-state angular distribution was fitted with the black-nucleus diffraction model of Blair using an interaction radius of 5.89×${10}^{-13\mathrm{}}$ cm. The angular distribution for the $Q=-3.95\mathrm{}$-Mev group was fitted with ${\left[j_2\mathrm{}\right(\mathrm{qR}\left)\right]}^2$ using an interaction radius of $R=5.9\mathrm{}\times {10}^{-13\mathrm{}}$ cm. With the same interaction radius, a best fit to the data for the unresolved doublet, $Q=-4.91\mathrm{}$ and -5.10 Mev, was obtained using the sum ${\left[j_1\mathrm{}\right(\mathrm{qR}\left)\right]}^2+{\left[j_3\mathrm{}\right(\mathrm{qR}\left)\right]}^2$. The best fit by odd-order spherical Bessel functions is consistent with the assignment of negative parity to both the 4.91- and 5.10-Mev levels.