Non-LTE Model Atmospheres for Late-Type Stars. II. Restricted Non-LTE Calculations for A Solar-Like Atmosphere

Carlos Allende Prieto, Ivan - Hubeny, David L. Lambert

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

We test our knowledge of the atomic opacity in the solar UV spectrum. Using the atomic data compiled in the first paper in this series from modern, publicly available databases, we perform calculations that are compared with space-based observations of the Sun. At wavelengths longer than about 2600 Å, LTE modeling can reproduce quite closely the observed fluxes; uncertainties in the atomic line data account fully for the differences between calculated and observed fluxes. At shorter wavelengths, departures from LTE appear to be important, since our LTE and restricted non-LTE calculations differ. Analysis of visible/near-IR Na I and O I lines, two species that produce a negligible absorption in the UV, shows that observed departures from LTE for these species can be reproduced very accurately with restricted (fixed atmospheric structure) non-LTE calculations.

Original languageEnglish (US)
Pages (from-to)1192-1202
Number of pages11
JournalAstrophysical Journal
Volume591
Issue number2 I
DOIs
StatePublished - Jul 10 2003
Externally publishedYes

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solar atmosphere
local thermodynamic equilibrium
atmospheres
stars
atmosphere
wavelength
atmospheric structure
opacity
wavelengths
modeling
calculation

Keywords

  • Line: Formation
  • Radiative transfer
  • Stars: Atmospheres
  • Sun: Abundances sun: Uv radiation

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Non-LTE Model Atmospheres for Late-Type Stars. II. Restricted Non-LTE Calculations for A Solar-Like Atmosphere. / Prieto, Carlos Allende; Hubeny, Ivan -; Lambert, David L.

In: Astrophysical Journal, Vol. 591, No. 2 I, 10.07.2003, p. 1192-1202.

Research output: Contribution to journalArticle

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