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Laboratory measurements indicate that the metastable ions of O(+) in reaction with N2 in the low-energy range (14 eV) react to form principally N2(+) , while the ion molecule reaction to form NO(+) has a very small probability. The ground-state O(+) reacts mainly to form NO(+). The abundance of metastable O(+2)D ions was determined using the observation that O(+2)D + N2 has a small cross section for forming NO(+). The ion-energy dependences for both reactions were measured within the energy range 1.0 to 500 eV.

Charge-changing collisions between K, Rb, Cs, Sb, Sr, I, Be, and Xe ions and the gases Ar, N2, and O2 were measured in the low energy range (4 to 130 keV). Similar measurements were made for K and Sr in the intermediate and high energy range (0.1 to 2 MeV) as well as rechecks on the previous measurements for Al in the intermediate and high energy ranges. High energy (0.2 to 2 MeV) measurements were made with Ag and Sb. Fast-particle detection was used to obtain values for the electron capture cross sections sigma 10 and sigma 21, the ion-stripping cross sections sigma 12, sigma 13, sigma 14, and sigma 15, and the neutral-atom-stripping cross section sigma 01. An oven was developed to provide a collision region containing oxygen mainly in the ground atomic state, but time permitted only preliminary tests without oxygen. (Author), Continuation of Contract AF 29(601)-6106 and Contract AF 29(601)-6614. See also Rept. no. GA-6738, AD-630 137.

The effect of addition on internal energy to the ion or neutral reactant in an ion-neutral process has been investigated. Changes in the cross section for certain processes are reported and a change in the state of excitation of the final product can in some cases be postulated. The reactions between O(+) + N2, N(+) + N2, N(+) + O2, N2(+) + O2, and N2(+) + O were considered. Where the cross section was found to increase with addition of internal energy to either the ion or the neutral, an approach to near resonance was, in some cases, found to have occurred. In such cases one or the other of the product particles may be produced in an exicted state. When the internal energy change is small compared to the energy defect for the reaction, little or no change in the cross section was observed.

The scattering of fast particles resulting from the bombardment of surfaces of polycrystalline copper and single-crystal silver by high-energy ions and atoms of helium, argon, and xenon is under investigation. The surface is bombarded with mass analyzed ions having energies of from 1 to 60 keV, and the fast scattered particles are detected as a function of angle. Resonance charge transfer of the primary ion beam is used to obtain the neutral beam. No significant difference is observed between angular distribution of scattering resulting from surface bombardment by ions and neutral atoms. (Author), Presented at the Rarefied Gas Dynamics Symposium (6th), Massachusetts Inst. of Tech., Cambridge, 22-26 Jul 68.