Cross Section for Elastic Scattering of Protons byN14

The elastic scattering cross section for protons on ${\mathrm{N}}^{14}$ was measured for bombarding energies from 900 kev to 4000 kev and for angles of 90°, 125.3°, 149.4°, and 160.9° in the center-of-mass system. A gas target chamber and a 6-mil thick CsI(Tl) crystal detector were used. The cross section was measured to an absolute accuracy of ±3.5%. An anomaly was observed at 3880±40 kev corresponding to a state in ${\mathrm{O}}^{15}$ at 11.00 Mev previously seen in the yield of gamma rays in the ${\mathrm{N}}^{14}(p, p^{\prime }\gamma ){\mathrm{N}}^{14}$ reaction.