Resonance strengths of selected resonances in the range $E_p=0.5\mathrm{}-0.9$ MeV in the ($p,\gamma$) reactions on ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{31}{}_{}{}^{}\mathrm{P}$, and ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}$ have been compared through relative yield measurements with targets consisting of mixtures of chemical compounds, each containing at least two of the isotopes of interest. Chemical composition of the targets was determined by Rutherford scattering of $\alpha$ particles. Absolute strengths were deduced by normalizing to a strength of $S=3.26\mathrm{}\pm 0.4$ eV for the $E_p=633\mathrm{}$ keV resonance in ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}(p,\gamma ){}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$.

NUCLEAR REACTIONS ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{31}{}_{}{}^{}\mathrm{P}$, ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}(p,\gamma )$, $E=0.5\mathrm{}-0.9$ MeV; measured $\sigma \left(E_p\right)$. Deduced resonance strengths. Natural targets.

• Received 2 November 1977

DOI:https://doi.org/10.1103/PhysRevC.17.1550