Accession Number : AD0858690

Title :   Energy Angular Distribution of Photoemission from the Ag-O-Cs Photocathode.

Descriptive Note : Final technical rept. Feb 66-Apr 68,

Corporate Author : NORTHWESTERN UNIV EVANSTON IL LINDHEIMER ASTRONOMICAL RESEARCH CENTER

Personal Author(s) : Burns, Jay

Report Date : FEB 1969

Pagination or Media Count : 56

Abstract : Angular distribution measurements on both semitransparent and opaque S-1 photocathodes show peaks in the distribution that give evidence for crystal orientation in these photosurfaces. When correction is made for electron refraction in going from the solid into the vacuum, the internal angular distribution of photoelectrons is found to exhibit peaks that lie along principal low-index directions of the hexagonal Cs2O crystal, assuming the cathode to consist of microcrystals of Cs2O with their c-axes perpendicular to the surface and with random rotation in azimuth about the surface normal. Two possible mechanisms are suggested to account for the observed angular distribution peaks. One envisions the angular distribution as resulting from the photon absorption event in which the internal photoelectron is initially excited; the other considers the angular orientation to be the result of a number of phonon elastic scattering events that takes place as the internal photoelectron moves to the surface. (Author)

Descriptors :   (*PHOTOCATHODES, PHOTOELECTRIC EFFECT), PHOTOELECTRONS, DISTRIBUTION, SILVER, CESIUM COMPOUNDS, OXIDES, ELECTRONS, ENERGY, BAND THEORY OF SOLIDS.

Subject Categories : Electrical and Electronic Equipment
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE