Mg I emission lines at 12 and 18 mu m in K giants

@article{Sundqvist2008MgIE,
  title={Mg I emission lines at 12 and 18 mu m in K giants},
  author={J. Sundqvist and N. Ryde and G. Harper and A. Kruger and M. Richter},
  journal={Astronomy and Astrophysics},
  year={2008},
  volume={486},
  pages={985-993}
}
Context. The solar mid-infrared metallic emission lines have already been observed and analyzed well, and the formation scenario of the Mg I 12 mu m lines has been known for more than a decade. Detections of stellar emission at 12 mu m have, however, been limited to Mg I in very few objects. Previous modeling attempts have been made only for Procyon and two cool evolved stars, with unsatisfactory results for the latter. This prevents the lines' long predicted usage as probes of stellar magnetic… Expand

Figures and Tables from this paper

Mg line formation in late-type stellar atmospheres: II. Calculations in a grid of 1D models
Mg is the alpha element of choice for Galactic population and chemical evolution studies as it is easily detectable in all late-type stars. Such studies require precise elemental abundances, and thusExpand
Non-LTE aluminium abundances in late-type stars
Aluminium plays a key role in studies of the chemical enrichment of the Galaxy and of globular clusters. However, strong deviations from LTE (non-LTE) are known to significantly affect the inferredExpand
NLTE analysis of Co i /Co ii lines in spectra of cool stars with new laboratory hyperfine splitting constants
The analysis of stellar abundances for odd-Z Fe-peak elements requires accurate non-local thermodynamic equilibrium (NLTE) modelling of spectral lines fully taking into account the hyperfineExpand
Mg line formation in late-type stellar atmospheres - I. The model atom
Context. Magnesium is an element of significant astrophysical importance, often traced in late-type stars using lines of neutral magnesium, which is expected to be subject to departures from localExpand
Systematic trend of water vapour absorption in red giant atmospheres revealed by high resolution TEXES 12 mu m spectra
Context. The structures of the outer atmospheres of red giants are very complex. Recent interpretations of a range of different observations have led to contradictory views of these regions. It isExpand
The NLTE Analyses of Carbon Emission Lines in the Atmospheres of O and B type Stars
We present a model atom for C I - C II - C III - C IV using the most up-to-date atomic data and evaluated the non-local thermodynamic equilibrium (NLTE) line formation in classical 1D atmosphericExpand
NLTE abundances of Mn in a sample of metal-poor stars ⋆
Aims. Following our solar work, we perform NLTE calculations of the Mn abundance for fourteen stars with [Fe/H] from 0 to -2.5, mainly to show how NLTE affects Mn abundances in cool stars ofExpand
NLTE Line Formation for Mg i and Mg ii in the Atmospheres of B–A–F–G–K Stars
Non-local thermodynamical equilibrium (NLTE) line formation for Mg I and Mg II lines is considered in classical 1D-LTE model atmospheres of the Sun and 17 stars with reliable atmospheric parametersExpand
Modelling the spectrum of Mg in cool stars
The astrophysical importance of Mg, together with its unique range of spectral features in late-type stars, plus its relative simplicity from an atomic physics point of view, makes it a prime targetExpand
The 44Ti-powered spectrum of SN 1987A
SN 1987A provides a unique opportunity to study the evolution of a supernova from explosion into very late phases. Owing to the rich chemical structure, the multitude of physical processes involvedExpand
...
1
2
...

References

SHOWING 1-10 OF 38 REFERENCES
Modeling the Infrared Magnesium and Hydrogen Lines from Quiet and Active Solar Regions
The emission lines of Mg I at 7.4, 12.2, and 12.3 µm are now known to be formed in the upper photosphere; the line emission is due to collisional coupling of higher levels with the continuum togetherExpand
Formation of the infrared emission lines of Mg I in the solar atmosphere
A non-LTE radiative transfer investigation of the emission lines is conducted at 7 and 12 microns using a realistic atomic model for neutral magnesium. An average quiet sun atmospheric model is usedExpand
Non-LTE line formation for heavy elements in four very metal-poor stars
Aims. Stellar parameters and abundances of Na, Mg, Al, K, Ca, Sr, Ba, and Eu are determined for four very metal-poor (VMP) stars (−2.15 ≥ [Fe/H] ≥− 2.66). For two of them, HD 84937 and HD 122563, theExpand
Abundances of Na, Mg and Al in nearby metal-poor stars
To determine the population membership of nearby stars we explore abundance results obtained for the light neutron- rich elements 23 Na and 27 Al in a small sample of moderately metal-poor stars.Expand
ISO-SWS calibration and the accurate modelling of cool-star atmospheres - III. A0 to G2 stars
Vega, Sirius, Beta Leo, Alpha Car and Alpha Cen A belong to a sample of twenty stellar sources used for the calibration of the detectors of the Short-Wavelength Spectrometer on board the InfraredExpand
New light on stellar abundance analyses: Departures from LTE and homogeneity.
▪ Abstract The information on the chemical compositions of stars encoded in their spectra plays a central role in contemporary astrophysics. Stellar element abundances are, however, not observed: toExpand
Detection of Water Vapor in the Photosphere of Arcturus
We report detections of pure rotation lines of OH and H2O in the K1.5 III red-giant star Arcturus (α Bootis) using high-resolution, infrared spectra covering the regions 806 −822cm −1 (12.2 −12.4 µm)Expand
A fine analysis of calcium and iron lines in the spectrum of the K0 giant Pollux : accurate fundamental parameters
Yellow and red spectral regions containing calcium and iron lines have been observed for the bright K0 III standard Pollux (β Gem). A fine and detailed model atmosphere analysis of the resultingExpand
The impulse approximation for the broadening of Mg I infrared lines by collisions with neutral hydrogen
The broadening of infrared lines, resulting from transitions between high nl levels, with l=n-i or n-2, is due to the l-mixing collisions, induced by the Rydberg electron-hydrogen interaction.Expand
Mg I as a probe of the solar chromosphere: the atomic model
This paper presents a complete atomic model for Mg I line synthesis, where all the atomic parameters are based on recent experimental and theoretical data. It is shown how the computed profiles atExpand
...
1
2
3
4
...