Accession Number : AD0780456

Title :   Inelastic Collisions of Excited Atoms.

Descriptive Note : Annual rept.,

Corporate Author : STANFORD RESEARCH INST MENLO PARK CALIF

Personal Author(s) : Peterson,James R.

Report Date : 19 JUN 1974

Pagination or Media Count : 20

Abstract : The research effort is concerned with interactions of metastable electronically excited atoms with ground state atoms and molecules. Principal attention recently has been devoted to the study of ionization processes in the collisions of He(*) (2 doublet S) with ground state He: the reaction He(*) + He to He(+) + He + e(-). Experimental measurements were made using our metastable atom differential scattering apparatus. The experiment represents the first successful measurement of the collisional ionization of metastable atoms at these low energies, and is the first detailed analysis of the product ion energies and angles that has been made at any energy. Three separate ionization processes have been clearly identified, and at least one more appears to be present in the data. It has been possible to interpret all these processes in terms of specific interactions between molecular states in the collision complex.

Descriptors :   *Helium, *Gas ionization, *Inelastic scattering, Potential energy, Inelastic scattering, Metastable state, Ground state, Excitation, Particle collisions, Reaction kinetics, Atomic energy levels, Energy transfer

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE