The ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}(p, \gamma ){}_{}{}^{22}{}_{}{}^{}\mathrm{Ne}$ and ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}(p, p_1\gamma ){}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ reactions have been studied in the energy range $E_p=0.5-2.0\mathrm{}$ MeV. The absolute resonance strengths $S=13\mathrm{}\pm 2$ eV and 0.20 ± 0.03 keV have been obtained for the first time in the ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}(p, \gamma ){}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ and ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}(p, p_1\gamma ){}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ reactions at $E_p=1205\mathrm{} \mathrm{and} 1090$ keV, respectively. The absolute resonance strengths of 25 ($p, \gamma$) and 27 ($p, p_1\gamma$) resonances in ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ have been determined relative to these values. The strengths $S=1.6\mathrm{}\pm 0.3 \mathrm{and} 21\pm 2$ eV for the ($p, \gamma$) resonances at $E_p=1169\mathrm{} \mathrm{and} 1278$ keV in ${}_{}{}^{21}{}_{}{}^{}\mathrm{Na}$ and ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, respectively, have been remeasured. The total widths have been determined for 24 resonances in ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ using a thin ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}$ target. The $\gamma$-ray decay properties of resonances in ${}_{}{}^{22}{}_{}{}^{}\mathrm{Na}$ and the astrophysical importance of the $p, \gamma$ resonance strengths in ${}_{}{}^{21,22,23}{}_{}{}^{}\mathrm{Na}$ are discussed.

NUCLEAR REACTIONS ${}_{}{}^{21}{}_{}{}^{}\mathrm{Ne}(p, \gamma )$,($p, p_1\gamma$), $E=0.5-2.0\mathrm{}$ MeV, ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}(p, \gamma )$, $E=1.2\mathrm{}$ MeV, ${}_{}{}^{22}{}_{}{}^{}\mathrm{Ne}(p, \gamma )$ $E=1.3\mathrm{}$ MeV; measured $\sigma \mathrm{}\left(E\right)\mathrm{}$; deduced resonance strengths. Enriched targets.

• Received 1 June 1976

DOI:https://doi.org/10.1103/PhysRevC.15.579