Resonance enhancement of electron collision rates for fluorinelike ions
Abstract
The distortedwave approximation and similar weakcoupling methods are frequently used to calculate electron collision cross sections for studies of astrophysical and laboratory plasmas. Autoionizing resonances neglected in these approximations can significantly enhance the calculated rates for collisional excitation of some transitions in highly charged ions. We investigated the effects of such resonances on the excitation rates for n = 2 to n = 2 transitions in fluorinelike Fe, Se, Mo, Ag, Xe, and Eu. The background excitation rates were calculated using a relativistic distortedwave approximation, and the detailed Auger and radiative rates were calculated using a multiconfiguration DiracFock model. The largest effect is on the electricdipoleforbidden transitions. The enhancement diminishes with increasing atomic number for all transitions.
 Authors:
 Publication Date:
 Research Org.:
 High Temperature Physics Division, University of California, Lawrence Livermore National Laboratory, Livermore, California 94550
 OSTI Identifier:
 6015824
 DOE Contract Number:
 W7405ENG48
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Phys. Rev. A; (United States); Journal Volume: 36:7
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; EUROPIUM IONS; ELECTRONION COLLISIONS; IRON IONS; MOLYBDENUM IONS; SELENIUM IONS; SILVER; XENON IONS; AUGER EFFECT; AUTOIONIZATION; CROSS SECTIONS; DISTORTED WAVE THEORY; E1TRANSITIONS; EXCITATION; MULTICHARGED IONS; RADIATIVE DECAY; RESONANCE; CHARGED PARTICLES; COLLISIONS; ELECTRON COLLISIONS; ELEMENTS; ENERGYLEVEL TRANSITIONS; ION COLLISIONS; IONIZATION; IONS; METALS; MULTIPOLE TRANSITIONS; TRANSITION ELEMENTS; 640304*  Atomic, Molecular & Chemical Physics Collision Phenomena
Citation Formats
Reed, K.J., Chen, M.H., and Hazi, A.U. Resonance enhancement of electron collision rates for fluorinelike ions. United States: N. p., 1987.
Web. doi:10.1103/PhysRevA.36.3117.
Reed, K.J., Chen, M.H., & Hazi, A.U. Resonance enhancement of electron collision rates for fluorinelike ions. United States. doi:10.1103/PhysRevA.36.3117.
Reed, K.J., Chen, M.H., and Hazi, A.U. 1987.
"Resonance enhancement of electron collision rates for fluorinelike ions". United States.
doi:10.1103/PhysRevA.36.3117.
@article{osti_6015824,
title = {Resonance enhancement of electron collision rates for fluorinelike ions},
author = {Reed, K.J. and Chen, M.H. and Hazi, A.U.},
abstractNote = {The distortedwave approximation and similar weakcoupling methods are frequently used to calculate electron collision cross sections for studies of astrophysical and laboratory plasmas. Autoionizing resonances neglected in these approximations can significantly enhance the calculated rates for collisional excitation of some transitions in highly charged ions. We investigated the effects of such resonances on the excitation rates for n = 2 to n = 2 transitions in fluorinelike Fe, Se, Mo, Ag, Xe, and Eu. The background excitation rates were calculated using a relativistic distortedwave approximation, and the detailed Auger and radiative rates were calculated using a multiconfiguration DiracFock model. The largest effect is on the electricdipoleforbidden transitions. The enhancement diminishes with increasing atomic number for all transitions.},
doi = {10.1103/PhysRevA.36.3117},
journal = {Phys. Rev. A; (United States)},
number = ,
volume = 36:7,
place = {United States},
year = 1987,
month =
}

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