Electronic excitation of helium and krypton by electron impact
Thesis/Dissertation
·
OSTI ID:5445924
A crossed-beam electron impact spectrometer is modified to enable the study of near-threshold electronic excitation of He, and Kr by electron impact. Absolute differential cross sections for excitation of the individual n = 2 states of He and 4p/sup 5/5s states of Kr are measured within the first four electron volts of threshold. In He, pronounced angle-dependent structures are apparent in the threshold excitation of the 2/sup 3/P state and in the near-threshold excitation of the 2/sup 3/S state. These experimental observations, when viewed in light of recent theoretical considerations, suggest the existence of a new /sup 2/P resonance near 20.8 eV. The results on Kr demonstrate that the angular momentum of the Kr/sup +/ ion core (4p/sup 5/) has a strong influence on the excitation cross sections, both on the relative magnitudes of the cross sections and on the relative strengths of resonant structures in the excitation functions. The angular momentum of the entire electron cloud of an excited state has less of an effect on the cross sections. It manifests itself primarily in the relative magnitudes of the two metastable cross sections. These observations emphasize the weakness of the coupling between the core and the outer electrons in the electron-Kr system.
- Research Organization:
- Yale Univ., New Haven, CT (USA)
- OSTI ID:
- 5445924
- Country of Publication:
- United States
- Language:
- English
Similar Records
Threshold photoelectron source for the study of low-energy electron scattering: Total cross section for electron scattering from krypton in the energy range from 14 meV to 20 eV
Electron-impact excitation of He: Threshold region
Electronic structure and angular momentum coupling as reflected in electron excitation out of rare-gas metastable levels: Excitation cross sections of krypton
Journal Article
·
Tue Dec 14 23:00:00 EST 2010
· Physical Review. A
·
OSTI ID:21528888
Electron-impact excitation of He: Threshold region
Journal Article
·
Mon Jun 01 00:00:00 EDT 1981
· Phys. Rev. A; (United States)
·
OSTI ID:6333634
Electronic structure and angular momentum coupling as reflected in electron excitation out of rare-gas metastable levels: Excitation cross sections of krypton
Journal Article
·
Tue Feb 14 23:00:00 EST 2006
· Physical Review. A
·
OSTI ID:20974593
Related Subjects
640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR MOMENTUM
ATOM COLLISIONS
BEAMS
COLLIDING BEAMS
COLLISIONS
COUPLING
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELEMENTS
ENERGY
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXPERIMENTAL DATA
FLUIDS
GASES
HELIUM
INFORMATION
KRYPTON
MEASURING INSTRUMENTS
NONMETALS
NUMERICAL DATA
RARE GASES
SPECTROMETERS
THRESHOLD ENERGY
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR MOMENTUM
ATOM COLLISIONS
BEAMS
COLLIDING BEAMS
COLLISIONS
COUPLING
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELEMENTS
ENERGY
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXPERIMENTAL DATA
FLUIDS
GASES
HELIUM
INFORMATION
KRYPTON
MEASURING INSTRUMENTS
NONMETALS
NUMERICAL DATA
RARE GASES
SPECTROMETERS
THRESHOLD ENERGY