L-subshells ionization of Yb and Au by fast heavy ions

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

OSTI ID:5189915

Malhi, N B

This work addresses the problem of L-subshell ionization by fast heavy ions incident on solid targets. Measurements of L x-ray production following bombardment of Yb and Au solid targets by {sup 1}H, {sup 7}Li, {sup 9}Be, {sup 12}C, {sup 14}N, {sup 19}F, and {sup 28}Si ions for an incident energy range of 0.5-3.0 MeV/amu have been done. Throughout this work the x-ray production cross sections {sigma}{sub L{sub {alpha}1.2}} and {sigma}{sub L{sub {gamma}2.3,(6)}} for the specified targets by incident ions of Le, Be, C, N, F, and Si ions have been measured. The author's main interest has been directed toward the measurements of the x-ray intensity ratios, L{sub {alpha}1,2}/L{sub {gamma}2.3,(6)} as a function of projectile velocity (E{sub p}/amu) and projectile atomic number Z{sub 1}. This ratio is directly related to the ratio of ionization cross sections for L{sub III}- and L{sub I}-subshells. He observed that there is a large systematic change in the energy dependence of the peak structure of the x-ray yield ratio L{sub {alpha}1,2}/L{sub {gamma}2.3,(6)}, which he believes is related to distortion of the 2s bound electron wave function in the entrance channel. The peak structure only exists because of the 2s{sub 1/2} nature of the L{sub 1}, which indicates a strong distortion in the initial target electron state, by the incoming projectile, for the 2s{sub 1/2} electrons in the L{sub I}-subshell. This distortion increases with increasing projectile atomic Z{sup 1}. The x-ray yield ratios and the production cross sections have been compared to several theories that try to explain the mechanisms of inner shell ionization. A lack of agreement between the data and the published theories suggests the need of an improvement in the theoretical description of inner shell ionization by fast heavy ions.

• Research Organization: Kansas State Univ., Manhattan, KS (United States)
• OSTI ID: 5189915
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
BEAMS
BERYLLIUM IONS
CARBON IONS
CHARGED PARTICLES
COLLISIONS
COUPLED CHANNEL THEORY
CROSS SECTIONS
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY RANGE
FLUORINE IONS
FUNCTIONS
GOLD
HEAVY IONS
HYDROGEN IONS
INNER-SHELL IONIZATION
ION BEAMS
ION COLLISIONS
ION-ATOM COLLISIONS
IONIZATION
IONIZING RADIATIONS
IONS
LITHIUM IONS
METALS
MEV RANGE
MEV RANGE 01-10
NITROGEN IONS
RADIATIONS
RARE EARTHS
SILICON IONS
TRANSITION ELEMENTS
WAVE FUNCTIONS
X RADIATION
YTTERBIUM