Electron impact ionization at low and intermediate energy; the asymmetric (e,2e)-process

Conference · Fri Jan 01 04:00:00 EST 1982 · AIP Conf. Proc.; (United States)

OSTI ID:5821824

Ehrhardt, H

The goal of the present paper is the qualitative and quantitative understanding of the electron impact ionization process for impact energies E/sub 0/ reaching from threshold (IP) to 500 eV. At low energies IP less than or equal to E/sub 0/ less than or equal to 2-3 IP all three scattering amplitudes (direct, momentum exchange, particle exchange) essentially contribute to the scattering and produce rapidly varying triple differential cross sections with respect to scattering angle theta/sub a/ and the angle of ejection theta/sub b/ of an electron. For intermediate (3.IP less than or equal to E/sub 0/ less than or equal to 10.IP) and for high impact energy (E/sub 0/ greater than or equal to 10.IP) the (e,2e) angular correlation spectrum contains only two peaks, namely the socalled binary and the recoil peak. The angular position and the intensity distribution of the binary peak contains information about the dynamics of the binary collision, the interaction between impinging electron and an atomic electron, and the momentum distribution of the atomic electron, which is ejected by the collision. The recoil peak, which is for intermediate impact energies more intense than the binary peak, is only scarcely understood and seems to be quite sensitive to correlation effects in the scattering system. For the first time a second order scattering approximation has been applied being able to describe quite well intensity, angular position and the shape of the recoil peak for the ionization of helium at E/sub 0/ = 500 eV.

• Research Organization: Univ. of Kaiserslautern, West Germany
• OSTI ID: 5821824
• Report Number(s): CONF-820245-
• Conference Information: Journal Name: AIP Conf. Proc.; (United States) Journal Volume: 86
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
ANGULAR DISTRIBUTION
ATOM COLLISIONS
COLLISIONS
CORRELATIONS
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
DISTRIBUTION
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELEMENTS
ENERGY RANGE
ENERGY SPECTRA
EV RANGE
EV RANGE 100-1000
FLUIDS
GASES
HELIUM
INFORMATION
IONIZATION
NONMETALS
NUMERICAL DATA
RARE GASES
RECOILS
SCATTERING
SCATTERING AMPLITUDES
SPECTRA
THEORETICAL DATA