State-selective nonresonant transfer excitation in 50--400-keV sup 3 He sup + +H sub 2 and He collisions

Journal Article · Fri Feb 01 04:00:00 EST 1991 · Physical Review, A; (USA)

DOI:https://doi.org/10.1103/PhysRevA.43.1621· OSTI ID:5715711

Jain, A ^[1]; Shingal, R ^[2]; Zouros, T J.M. ^[3]

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1. Department of Physics, Florida A M University, Box 981, Tallahassee, Florida 32307 (US)
2. Department of Physics, Kansas State University, Manhattan, Kansas 66506 (USA)
3. Department of Physics, University of Crete, Iraklion and Foundation for Research an Technology-Hellas (FORTH), Iraklion (Greece)

Cross sections for nonresonant transfer excitation (NTE) are calculated for collisions of {sup 3}He{sup +} with H{sub 2} (2H) and He targets in the 50--500-keV impact-energy range. Single-electron capture probabilities to the 2{ital s} and 2{ital p} orbitals of He and single-electron excitation probabilities for He{sup +} (1{ital s}{r arrow}2{ital s} or 2{ital p}) transitions are independently computed, as a function of impact parameter, using the semiclassical multichannel-impact-parameter model with an expansion in atomic orbitals placed either on one or both centers. NTE cross sections for the (2{ital s}{sup 2}){sup 1}{ital S}, (2{ital p}{sup 2}){sup 1}{ital D}, and (2{ital s}2{ital p}){sup 1}{ital P} states, computed in the independent-electron model, are compared with the recent high-resolution electron data for transfer excitation into these states. For He{sup +}+H{sub 2} collisions, NTE is found to contribute primarily at the low collision energies, dropping off at the higher energies. On the contrary, for the symmetric He{sup +}+He collisions, NTE cross sections do not drop off with impact energy as expected. In the case of the (2{ital p}{sup 2}){sup 1}{ital D} state, an increase in the cross section, similar to the experimental data, is seen. However, in both cases, the calculated cross section seems to be larger than the experimental data.

• OSTI ID: 5715711
• Journal Information: Physical Review, A; (USA), Journal Name: Physical Review, A; (USA) Vol. 43:3; ISSN 1050-2947; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
CAPTURE
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELECTRON CAPTURE
ELEMENTS
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
EXCITATION
FLUIDS
GASES
HELIUM
HELIUM IONS
HYDROGEN
ION COLLISIONS
ION-ATOM COLLISIONS
ION-MOLECULE COLLISIONS
IONS
KEV RANGE
KEV RANGE 10-100
KEV RANGE 100-1000
MOLECULE COLLISIONS
NONMETALS
RARE GASES