Accession Number : AD0778834

Title :   A Time Resolved Drift Tube Study of Electron Avalanches in Oxygen.

Descriptive Note : Technical rept.,


Personal Author(s) : Corbin,Robert J. ; Goodson,Donald W. ; Frommhold,Lothar

Report Date : 10 SEP 1973

Pagination or Media Count : 126

Abstract : In order to investigate pre-breakdown electron avalanches initiated in uniform fields in a high purity gas, a bakeable time resolved drift tube capable of operating near breakdown was constructed. The results of an investigation of electronic and ionic reactions in oxygen at pressures of 4, 8, 16, and 32 torr are reported as a function of E/p (ratio of electric field strength to pressure). The electron avalanches are started by photoelectrons. The electrons are known to undergo both ionization and dissociative attachment. It is also known that the atomic O(-) thus formed may further undergo detachment, charge transfer, or three body ion conversion. O2(-), O3(-), and O4(-) were also observed. In order to generate computed pulse shapes, continuity equations for the densities of the various charge carriers in the reactions were integrated and the solutions programmed. Results in oxygen gave new measurements of Townsend's first ionization coefficient, the attachment, detachment, and total loss reaction rates attributed to atomic O(-) as well as confirming measurements of the detachment and effective attachment reaction rates attributed to O2(-) and O3(-). (Modified author abstract)

Descriptors :   *Oxygen, *Gas ionization, Rates, Electron transitions, Charge transfer, Ions, Photoionization, Electron capture, Photoelectrons, Reaction kinetics

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE