Inclusion of electron transfer in the calculation of K/sup n/L/sup v/ multiple vacancy production by ion impact

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6795054

Becker, R L; Ford, A L; Reading, J F

Measurements of K x-ray or Auger satellite (and hypersatellite) intensities provide information on KL/sup v/ (and K/sup 2/L/sup v/) hole production in close collisions of ions with atoms. The L-shell vacancy distributions usually are nearly binomial. The binomial distribution follows immediately from a statistical model in which the creations of the various holes are regarded as mutually independent. This distribution is specified by a single parameter, p, the mean L-shell vacancy probability per electron, which can depend on the speed v, the nuclear charge Z and the ionic charge q of the projectile, and on the nuclear charge of the target. Almost all calculations of p, aside from our work, have been limited to first-order collision approximations. Moreover, all such calculations have included only impact ionization and, consequently, have neglected electron transfer to the projectile. The first-order calculations have had enough success for proton and alpha-particle impact to remain in vogue for a decade, but they predict that p is proportional to Z/sup 2/, whereas anti p must remain less than or equal to 1, which requires a unitary collision approximation. We have obtained the saturation of p with Z in two unitary schemes, the first Magnus approximation and the more refined coupled-channel approximation. In both schemes we used a single-centered expansion (SCE) in spin-orbitals representing bound and unbound states of the target. Typically, we employ ten radial functions for each of four angular momenta (s, p, d, and f states).

• Research Organization: Oak Ridge National Lab., TN (USA); Texas A and M Univ., College Station (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6795054
• Report Number(s): CONF-840829-1; ON: DE84016596
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
CAPTURE
COLLISIONS
COUPLED CHANNEL THEORY
COUPLING
ELECTRON CAPTURE
ELECTRONIC STRUCTURE
INTERMEDIATE COUPLING
ION COLLISIONS
ION-ATOM COLLISIONS
L SHELL
L-S COUPLING
MATHEMATICAL MODELS