Accession Number : AD0688519

Title :   ELECTRON IMPACT DESORPTION OF IONS AND NEUTRALS FROM POLYCRYSTALLINE TUNGSTEN,

Corporate Author : ILLINOIS UNIV URBANA COORDINATED SCIENCE LAB

Personal Author(s) : Nishijima,Mitsuaki

Report Date : APR 1969

Pagination or Media Count : 314

Abstract : A cylindrical magnetic spectrometer has been constructed for the study of electron impact desorption of gases from solid surfaces. The instrument has been applied to the study of polycrystalline tungsten with O2, CO, H2, N2, CO2, and H2O adsorbed. The quantities which have been measured are: ion species desorbed, ion energy distributions, ionic and total desorption cross sections, and threshold energies. Measurements were also made on the kinetics of the adsorption-desorption processes and some measurements of thermal processes. The dependence on electron energy of the O(+) ion desorption cross section and total desorption cross section for O2/W indicates that the neutralization of ions is not the only but is a dominant mechanism for neutral desorption. (Author)

Descriptors :   (*TUNGSTEN, ADSORPTION), (*SURFACE PROPERTIES, TUNGSTEN), MASS SPECTROSCOPY, SPECTRUM ANALYZERS, OXYGEN, CARBON MONOXIDE, HYDROGEN, NITROGEN, WATER, REACTION KINETICS, THESES

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE