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ON the FINE STRUCTURE SPLITTING of the 3p43d 4D5/2 and 3p43d 4D7/2 LEVELS of Fe X

Judge, Philip G. LU ; Hutton, Roger LU ; Li, Wenxian and Brage, Tomas LU (2016) In Astrophysical Journal 833(2).
Abstract

We study UV spectra obtained with the SO82-B slit spectrograph on board SKYLAB to estimate the fine structure (FS) splitting of the Cl-like and levels of Fe x. The splitting is of interest because the Zeeman effect mixes these levels, producing a "magnetically induced transition" (MIT) from to for modest magnetic field strengths characteristic of the active solar corona. We estimate the splitting using the Ritz combination formula applied to two lines in the UV region of the spectrum close to 1603.2 Å, which decay from the level to these two lower levels. The MIT and accompanying spin-forbidden transition lie near 257 Å. By careful inspection of a deep exposure obtained with the S082B instrument, we derive a splitting of... (More)

We study UV spectra obtained with the SO82-B slit spectrograph on board SKYLAB to estimate the fine structure (FS) splitting of the Cl-like and levels of Fe x. The splitting is of interest because the Zeeman effect mixes these levels, producing a "magnetically induced transition" (MIT) from to for modest magnetic field strengths characteristic of the active solar corona. We estimate the splitting using the Ritz combination formula applied to two lines in the UV region of the spectrum close to 1603.2 Å, which decay from the level to these two lower levels. The MIT and accompanying spin-forbidden transition lie near 257 Å. By careful inspection of a deep exposure obtained with the S082B instrument, we derive a splitting of cm-1. The upper limit arises because of a degeneracy between the effects of non-thermal line broadening and FS splitting for small values of the latter parameter. Although the data were recorded on photographic film, we solved for optimal values of line width and splitting of 8.3 ± 0.9 and 3.6 ± 2.7 cm-1.

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author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Sun: atmosphere, Sun: corona, Sun: magnetic fields
in
Astrophysical Journal
volume
833
issue
2
article number
185
publisher
American Astronomical Society
external identifiers
  • wos:000391169600060
  • scopus:85008154342
ISSN
0004-637X
DOI
10.3847/1538-4357/833/2/185
language
English
LU publication?
yes
id
50738b50-590d-4f5d-88f3-99912263ffb0
date added to LUP
2017-01-13 08:27:52
date last changed
2025-01-12 19:22:57
@article{50738b50-590d-4f5d-88f3-99912263ffb0,
  abstract     = {{<p>We study UV spectra obtained with the SO82-B slit spectrograph on board SKYLAB to estimate the fine structure (FS) splitting of the Cl-like and levels of Fe x. The splitting is of interest because the Zeeman effect mixes these levels, producing a "magnetically induced transition" (MIT) from to for modest magnetic field strengths characteristic of the active solar corona. We estimate the splitting using the Ritz combination formula applied to two lines in the UV region of the spectrum close to 1603.2 Å, which decay from the level to these two lower levels. The MIT and accompanying spin-forbidden transition lie near 257 Å. By careful inspection of a deep exposure obtained with the S082B instrument, we derive a splitting of cm<sup>-1</sup>. The upper limit arises because of a degeneracy between the effects of non-thermal line broadening and FS splitting for small values of the latter parameter. Although the data were recorded on photographic film, we solved for optimal values of line width and splitting of 8.3 ± 0.9 and 3.6 ± 2.7 cm<sup>-1</sup>.</p>}},
  author       = {{Judge, Philip G. and Hutton, Roger and Li, Wenxian and Brage, Tomas}},
  issn         = {{0004-637X}},
  keywords     = {{Sun: atmosphere; Sun: corona; Sun: magnetic fields}},
  language     = {{eng}},
  month        = {{12}},
  number       = {{2}},
  publisher    = {{American Astronomical Society}},
  series       = {{Astrophysical Journal}},
  title        = {{ON the FINE STRUCTURE SPLITTING of the 3p<sup>4</sup>3d <sup>4</sup>D<sub>5/2</sub> and 3p<sup>4</sup>3d <sup>4</sup>D<sub>7/2</sub> LEVELS of Fe X}},
  url          = {{http://dx.doi.org/10.3847/1538-4357/833/2/185}},
  doi          = {{10.3847/1538-4357/833/2/185}},
  volume       = {{833}},
  year         = {{2016}},
}