The resonances in the emission of gamma-radiation from fluorine bombarded by protons have been studied from 300 kev up to 850 kev. Resonances were observed at 334, 479, 590, 660, and 820 kev with width at half-intensity, respectively, of 3.2, 2.6, 37, 7.5, and 8.3 kev. The absolute cross sections at resonance were found to vary from ${0.4\times 10}^{-26\mathrm{}}$ ${\mathrm{cm}}^2$ for the resonance at 590 kev to ${5.9\times 10}^{-26\mathrm{}}$ ${\mathrm{cm}}^2$ for the resonance at 334 kev. These results and previous results for the resonances at higher energies were compared to the single level dispersion formula, and the values of partial widths due to proton re-emission were found to vary from 10 volts at the 1076-kev resonance to 5.7 kev for the 1363-kev resonance.

The resonance in the emission of 17-Mev gamma-radiation from lithium bombarded by protons at 440 kev was found to have an experimental width of 14 kev. The cross section for the reaction at the peak of the resonance is ${7.2\times 10}^{-27\mathrm{}}$ ${\mathrm{cm}}^2$. The resonance curve is not symmetrical and cannot be explained by the single level dispersion formula.

• Received 19 December 1947

DOI:https://doi.org/10.1103/PhysRev.73.666