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Title: Atomic data and spectral line intensities for Si XI

Abstract

Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Si XI. The configurations used are 2s{sup 2}, 2s2p, 2p{sup 2}, 2l3l', 2l4l' and 2s5l', with l = s,p and l' = s,p,d giving rise to 92 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies (35, 70, 105, 140, and 175 Ry) in the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, and R-Matrix results for the 2s{sup 2}, 2s2p, 2p{sup 2} configurations available in the literature, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10{sup 8}-10{sup 14} cm{sup -3} at an electron temperature of log T {sub e}(K) = 6.2, corresponding to the maximum abundance of Si XI. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database.

Authors:
 [1];  [2]
  1. NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  2. ARTEP, Inc., Columbia, MD 21044 (United States) and Naval Research Laboratory Washington, DC 20375 (United States). E-mail: landi@poppeo.nrl.navy.mil
Publication Date:
OSTI Identifier:
20976803
Resource Type:
Journal Article
Resource Relation:
Journal Name: Atomic Data and Nuclear Data Tables; Journal Volume: 93; Journal Issue: 2; Other Information: DOI: 10.1016/j.adt.2006.06.002; PII: S0092-640X(06)00074-X; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABUNDANCE; APPROXIMATIONS; BOLTZMANN STATISTICS; DISTORTED WAVE THEORY; ELECTRON BEAMS; ELECTRON COLLISIONS; ELECTRON DENSITY; ELECTRON TEMPERATURE; ENERGY LEVELS; EQUATIONS; EQUILIBRIUM; EXCITATION; FINE STRUCTURE; INTERMEDIATE COUPLING; NUCLEAR DATA COLLECTIONS; OSCILLATOR STRENGTHS; R MATRIX; RADIATIVE DECAY; SILICON

Citation Formats

Bhatia, A.K., and Landi, E.. Atomic data and spectral line intensities for Si XI. United States: N. p., 2007. Web. doi:10.1016/j.adt.2006.06.002.
Bhatia, A.K., & Landi, E.. Atomic data and spectral line intensities for Si XI. United States. doi:10.1016/j.adt.2006.06.002.
Bhatia, A.K., and Landi, E.. Thu . "Atomic data and spectral line intensities for Si XI". United States. doi:10.1016/j.adt.2006.06.002.
@article{osti_20976803,
title = {Atomic data and spectral line intensities for Si XI},
author = {Bhatia, A.K. and Landi, E.},
abstractNote = {Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Si XI. The configurations used are 2s{sup 2}, 2s2p, 2p{sup 2}, 2l3l', 2l4l' and 2s5l', with l = s,p and l' = s,p,d giving rise to 92 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies (35, 70, 105, 140, and 175 Ry) in the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates of the present work, and R-Matrix results for the 2s{sup 2}, 2s2p, 2p{sup 2} configurations available in the literature, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10{sup 8}-10{sup 14} cm{sup -3} at an electron temperature of log T {sub e}(K) = 6.2, corresponding to the maximum abundance of Si XI. Spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database.},
doi = {10.1016/j.adt.2006.06.002},
journal = {Atomic Data and Nuclear Data Tables},
number = 2,
volume = 93,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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