Accession Number : ADA135176

Title :   Production of Negative Ions by Electron Impact.

Descriptive Note : Final rept. 1 May 81-31 Oct 82,


Personal Author(s) : Srivastava,S K

PDF Url : ADA135176

Report Date : Oct 1982

Pagination or Media Count : 60

Abstract : Proposed future space-based beam weapons systems will most probably require an intense neutral particle beam for effective operation across geomagnetic field lines. Such neutral beams can most efficiently be obtained by stripping excess electrons from negative ion beams. The objective of this work is to study the process of dissociative attachment of electrons. Specifically, to measure the cross sections for polar dissociation and dissociative attachment for production of H(-). It is suspected that these dissociative attachment cross sections for the production of H(-) from alkali hydrides are large. The insight gained from this study will be extremely helpful in the fabrication of high current density H(-) beam sources for use in the production of intense neutral hydrogen beams. A selection of alkali hydride molecules will be investigated in order to determine the largest cross sections for the production of H(-) by electron impact. The angular distribution of the H(-) ions will be measured. An optimal vapor pressure for the efficient production of H(-) will be found. The feasibility of extending the proposed research to the deuterium bearing molecule will be determined.

Descriptors :   *Ion beams, *Anions, *Chemical dissociation, Particle beams, Electrons, Attachment, Stripped atoms, Methodology, Cross sections, Electron impact spectra, Instrumentation

Subject Categories : Physical Chemistry
      Nuclear Physics & Elementary Particle Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE