CHARGE-TRANSFER OF 0.5-, 1.5-, AND 5-KEV PROTONS WITH ATOMIC OXYGEN -ABSOLUTE DIFFERENTIAL AND INTEGRAL CROSS-SECTIONS

We report measurements of the absolute differential cross sections for charge-transfer scattering of 0.5-, 1.5-, and 5-keV protons by atomic oxygen at scattering angles between 0.01(0) and 2.6(0) in the laborat ory frame. Absolute integral cross sections are also reported and comp ared with previously published total cross sections. The measurements were made using a flowing gas target, which consisted of a mixture of atomic and molecular oxygen produced by passage of O-2 through a micro wave discharge. The cross sections for atomic oxygen were obtained by appropriate subtraction of the signal due to molecular oxygen from tha t due to the mixture of O and O-2.