Experimental studies of the influence of beam composition on elastic scattering yields of low energy sup 20 Ne ions

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1991

OSTI ID:5611278

Martin, A

The yields of elastically scattered ({theta}{sub lab} = 138{degree}) {sup 20}Ne ions from the surfaces of polycrystalline elemental samples of Ag, Sn, Au, and Pd have been measured as a function of the ionization potential V{sub i}, and the incident beam current, I{sub 0}, in the ion gun over a range of incident beam energies from 800 to 2,100 eV. Ion Scattering Spectroscopy (ISS) data were accumulated for elastically scattered incident Ne{sup +} ions and, when practical, for Ne{sup ++} ions partially neutralizing and scattering elastically in the singly charged state. The data indicate that a threshold for the elastic scattering yield exists for all the samples studied at V{sub i} {ge} 80V which is exhibited by a shift in the peak position of the normalized yield {tilde Y} to a lower (50-100 eV) incident beam energy. Upon consideration of the data, and in the light of calculations based upon a classical theory of ionization cross sections, the effect is attributed to the nature of the cross section for the formation of singly ionized {sup 20}Ne due to electronic collisions in the ion gun. The absolute elastic yields for the samples are compared, with Pd exhibiting the lowest yield at all values of the experimental parameters and with Ag, Au, and Sn yields greater by factors of approximately 5, 10 and 15 respectively. The elastic scattering yield vs. incident energy for Pd exhibits unique among the samples in this study and among those found in the literature. The implications of this for the theory of neutralization in ISS are briefly discussed.

• Research Organization: Clarkson Univ., Potsdam, NY (United States)
• OSTI ID: 5611278
• Country of Publication: United States
• Language: English

Related Subjects

665300* -- Interactions Between Beams & Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BEAM NEUTRALIZATION
CHARGED PARTICLES
COLLISIONS
COMPARATIVE EVALUATIONS
CRYSTALS
ELASTIC SCATTERING
ELEMENTS
EVALUATION
GOLD
ION COLLISIONS
ION SPECTROSCOPY
IONIZATION
IONS
LEAD
METALS
NEON IONS
POLYCRYSTALS
SCATTERING
SILVER
SPECTROSCOPY
SURFACES
TIN
TRANSITION ELEMENTS