Accession Number:

ADA229486

Title:

Theoretical Investigations of Negative Ions in a Hydrogen Source

Descriptive Note:

Final rept. 1 Sep 1987-31 Aug 1990

Corporate Author:

WAYNE STATE UNIV DETROIT MI DEPT OF PHYSICS AND ASTRONOMY

Personal Author(s):

Report Date:

1990-08-31

Pagination or Media Count:

103.0

Abstract:

The principal results of the research are two-fold. First, the time- dependent behavior of electron swarms in various atomic and molecular gases were obtained using a novel numerical procedure. The electrons injected in the gaseous source excite and ionize the atoms as well as molecules and, more importantly, cause dissociation and vibrational excitation of the molecular species. Second, the cross sections and the rates of negative ion production via the process of dissociative electron attachment to various light molecules were calculated. The role played by initial rovibrational excitation of the molecule in enhancing the rates of production of negative ion beams were investigated in detail. Since the processes of dissociative attachment and vibrational excitation are complementary in nature both proceed via the excitation of molecular hydrogen and its five isotopes were also examined. Very useful scaling law for these excitation cross sections were for vibrational excitation or deexcitation, by electron impact, of heavier isotopes of H2 from the corresponding sections for molecular hydrogen. Keywords Atomic, Molecular, Gases, Electron, Isotopes.

Subject Categories:

  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE