The cross section for ionization of atomic oxygen has been measured by using modulated atomic beam techniques. First the ratio of the cross sections for production of the molecular oxygen ion and for total ion production in collisions of electrons with oxygen molecules was measured. Then the ratio of the ionization cross section of the free oxygen atom and the cross section for production of the molecular ion in electron-molecule collisions was determined. From the previously known total ionization cross section of the molecule, and the measured ratios, the unknown cross sections were determined. The experimental results are compared with the calculations of Seaton.
- Received 13 October 1958
- Published in the issue dated February 1959
© 1959 The American Physical Society