Absolute differential and total cross sections for direct and charge-transfer scattering of keV protons by O2

Calculated and experimental differential direct, charge-transfer, and total scattering cross sections are presented for collisions of H+ with O2. Experimental cross sections are obtained for projectile energies of 0.5, 1.5, and 5.0 keV, and scattering angles of 0.15 deg. to 5 deg. while the theoretical results extend from 0.5 to 25 keV and encompass scattering angles from 0.01 deg. to 180 deg. We find good agreement between the calculated and measured differential and total cross sections. Also, a diffraction slit effect, which is target orientation dependent, is found in the differential scattering cross section. A theoretical explanation of the effect is presented