Comparison of L x-ray spectra from multi-stripped ions in P/sup +/ + Ar and S/sup +/ + Ar gas collisions at 100 keV

Conference · Wed Apr 01 04:00:00 EST 1981 · IEEE Trans. Nucl. Sci.; (United States)

OSTI ID:5474061

Peterson, R S; Furst, M; Hayden, H C; Smith, W W

Structure in the soft x-ray spectra from projectiles excited in ion-atom collisions at 100 keV has been observed. Previous spectral measurements on these collision systems using a curved crystal Bragg spectrometer were unable to experimentally resolve the multiplet structure. The present results are obtained with a grazing incidence monochrometer and clearly show the resolved structure from L x-rays of neon-like and flourine-like ions. The L x-ray spectra from phosphorus and sulfur ions after single collisions in argon gas targets are compared to establish x-ray line identifications. The individual spectra yield information on the collision mechanism involving the inner-shell promotion of L-shell electrons and the simultaneous outer-shell electron excitation. The model for L-shell vacancy production in asymmetric ion-atom collisions assumes that two 2p electrons of the lower-Z projectile are promoted via the 4fsigma molecular-orbital. Because this orbital is coupled to many empty molecular orbitals, the probability that one or two 2p electrons are promoted to higher orbitals is unity for ion-atom collisions where the L shells interpenetrate. The promotion leaves one or two 2p vacancies in the lower-Z atom after the collision. This model agrees well with experimental observations of energy loss and total vacancy production cross sections. However, the small L x-ray yields, which result after vacancy production, increase dramatically with the collision energy, indicating the possibility of strong outer-shell excitation mechanisms accompanying the inner-shell electron promotion.

• Research Organization: The University of Connecticut, Storrs, CT 06268
• OSTI ID: 5474061
• Report Number(s): CONF-801111-
• Conference Information: Journal Name: IEEE Trans. Nucl. Sci.; (United States) Journal Volume: NS-28:2
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ARGON
ATOM COLLISIONS
CHARGED PARTICLES
COLLISIONS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
EXCITATION
FERMIONS
FLUIDS
GASES
ION COLLISIONS
ION-ATOM COLLISIONS
IONIZING RADIATIONS
IONS
KEV RANGE
KEV RANGE 100-1000
LEPTONS
NONMETALS
PHOSPHORUS IONS
POINT DEFECTS
PROJECTILES
RADIATIONS
RARE GASES
SOFT X RADIATION
SPECTRA
SULFUR IONS
VACANCIES
WAVELENGTHS
X RADIATION
X-RAY SPECTRA