Proton-Oxygen Differential Scattering Cross Sections. II

The differential cross section for the elastic scattering of protons on ${\mathrm{O}}^{16}$ was measured for the laboratory energy range of 4.25 to 8.6 Mev. A differentially pumped gas scattering chamber with a CsI(Tl) scintillation detector was used. Measurements were made at the following center-of-mass scattering angles: 30° 2′, 54° 25′, 90° 0′, 103° 48′, 122° 57′, 140° 25′, 148° 50′, 166° 52′. Measurements were made at 0.0025- to 0.001-Mev intervals with a target thickness of 0.0025 to 0.001 Mev at 166°52′. The other angles were measured at 0.001- to 0.040-Mev intervals with a 0.001- to 0.003-Mev target. The energy spread of the beam was probably less than 0.003 Mev for all the work. The uncertainties in the measured cross sections were approximately ±0.5%. Twenty-two resonances were found.