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Title: Energy and angular distributions of electrons from ion impact on atomic and molecular hydrogen. IV. 28{endash}114-keV He{sup +} + H collisions

Abstract

Absolute ionization cross sections for 28{endash}114-keV helium ion impact on atomic hydrogen, differential in energy and angle of the ejected electrons, have been obtained from crossed-beam measurements and previously measured cross sections for molecular hydrogen targets. A radio frequency discharge source produced a mixed atomic and molecular target with a typical dissociation fraction of 74{percent}. Energy spectra were measured from 1.5 to 130 eV by an electrostatic analyzer with a resolution of 5{percent}. The angular range was 15{degree}{endash}160{degree}. Results are compared with calculations based on the first Born, continuum-distorted-wave{endash}eikonal-initial-state, and classical trajectory Monte Carlo methods. Total electron yields are obtained by combining calculations that are separately performed for liberating the target and projectile electrons. Model potentials are used to represent the interparticle-separation-dependent screening of the nuclear charges experienced by the electrons. Though projectile electron emission is a negligible component of the total ionization cross section for the present collision energies, its contribution is significant for particular regions of the spectrum of ejected electrons. Through comparison with our proton-impact data [Kerby {ital et} {ital al}., Phys. Rev. A {bold 51}, 2256 (1995)], differences and similarities are demonstrated owing to the common asymptotic charge of these two projectiles but differing nuclear chargesmore » and the electron carried by the He{sup +} ion. Comparisons are also made illustrating the differences between atomic and molecular hydrogen targets. {copyright} {ital 1996 The American Physical Society.}« less

Authors:
; ; ;  [1]; ;  [2]
  1. Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588-0111 (United States)
  2. Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6373 (United States)
Publication Date:
Research Org.:
Oak Ridge National Laboratory
OSTI Identifier:
277303
DOE Contract Number:  
AC05-84OR21400
Resource Type:
Journal Article
Journal Name:
Physical Review A
Additional Journal Information:
Journal Volume: 53; Journal Issue: 1; Other Information: PBD: Jan 1996
Country of Publication:
United States
Language:
English
Subject:
66 PHYSICS; HELIUM IONS; ION-ATOM COLLISIONS; HYDROGEN; ELECTRON EMISSION; ANGULAR DISTRIBUTION; ENERGY SPECTRA; EV RANGE; IONIZATION; KEV RANGE 10-100; KEV RANGE 100-1000

Citation Formats

Hsu, Y, Gealy, M W, Kerby, III, G W, Rudd, M E, Schultz, D R, and Reinhold, C O. Energy and angular distributions of electrons from ion impact on atomic and molecular hydrogen. IV. 28{endash}114-keV He{sup +} + H collisions. United States: N. p., 1996. Web. doi:10.1103/PhysRevA.53.303.
Hsu, Y, Gealy, M W, Kerby, III, G W, Rudd, M E, Schultz, D R, & Reinhold, C O. Energy and angular distributions of electrons from ion impact on atomic and molecular hydrogen. IV. 28{endash}114-keV He{sup +} + H collisions. United States. https://doi.org/10.1103/PhysRevA.53.303
Hsu, Y, Gealy, M W, Kerby, III, G W, Rudd, M E, Schultz, D R, and Reinhold, C O. Mon . "Energy and angular distributions of electrons from ion impact on atomic and molecular hydrogen. IV. 28{endash}114-keV He{sup +} + H collisions". United States. https://doi.org/10.1103/PhysRevA.53.303.
@article{osti_277303,
title = {Energy and angular distributions of electrons from ion impact on atomic and molecular hydrogen. IV. 28{endash}114-keV He{sup +} + H collisions},
author = {Hsu, Y and Gealy, M W and Kerby, III, G W and Rudd, M E and Schultz, D R and Reinhold, C O},
abstractNote = {Absolute ionization cross sections for 28{endash}114-keV helium ion impact on atomic hydrogen, differential in energy and angle of the ejected electrons, have been obtained from crossed-beam measurements and previously measured cross sections for molecular hydrogen targets. A radio frequency discharge source produced a mixed atomic and molecular target with a typical dissociation fraction of 74{percent}. Energy spectra were measured from 1.5 to 130 eV by an electrostatic analyzer with a resolution of 5{percent}. The angular range was 15{degree}{endash}160{degree}. Results are compared with calculations based on the first Born, continuum-distorted-wave{endash}eikonal-initial-state, and classical trajectory Monte Carlo methods. Total electron yields are obtained by combining calculations that are separately performed for liberating the target and projectile electrons. Model potentials are used to represent the interparticle-separation-dependent screening of the nuclear charges experienced by the electrons. Though projectile electron emission is a negligible component of the total ionization cross section for the present collision energies, its contribution is significant for particular regions of the spectrum of ejected electrons. Through comparison with our proton-impact data [Kerby {ital et} {ital al}., Phys. Rev. A {bold 51}, 2256 (1995)], differences and similarities are demonstrated owing to the common asymptotic charge of these two projectiles but differing nuclear charges and the electron carried by the He{sup +} ion. Comparisons are also made illustrating the differences between atomic and molecular hydrogen targets. {copyright} {ital 1996 The American Physical Society.}},
doi = {10.1103/PhysRevA.53.303},
url = {https://www.osti.gov/biblio/277303}, journal = {Physical Review A},
number = 1,
volume = 53,
place = {United States},
year = {1996},
month = {1}
}