Elastic and Inelastic Scattering of Protons byN14

Differential cross sections for the elastic scattering of protons by ${\mathrm{N}}^{14}$ have been measured for proton energies between 1.0 and 4.1 Mev at center-of-mass scattering angles of 90.0° and 168.1°. Above 3.5 Mev the study was extended to four additional angles, 140.8°, 125.3°, 54.7°, and 39.2°, to provide information on a broad resonance near 3.9 Mev and a narrower resonance at 3.980 Mev. These two resonances also exhibit a measurable width for inelastic scattering to the first excited state of ${\mathrm{N}}^{14}$ at 2.31 Mev. All measurements were made with a differentially-pumped scattering chamber containing natural nitrogen gas. The probable error in the cross section is estimated at 3%; the energies of the incident protons were determined to ±3 kev. The data were analyzed to provide information on the resonance energies $E_r$ and total widths $\Gamma$. Evidence was found for a previously unreported level with $E_r=2.535\mathrm{}$ Mev, $\Gamma \cong 1.8$ kev. From an investigation of the elastic and inelastic scattering data in the region of the level at 3.9 Mev it is concluded that the resonance is due to $d$-wave formation of a state of ${\mathrm{O}}^{15}$ having spin and parity ${\frac{5}{2}}^{+}$, with $E_r=3.878\mathrm{}\pm 0.008$ Mev, $\Gamma =85\mathrm{}\pm 8$ kev, ${\Gamma }_i=7\mathrm{}$ kev.