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The FeH Wing-Ford Band in Spectra of M Stars

Ricardo P. Schiavon·B. Barbuy·Patan D. Singh
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Abstract

We study the FeH Wing-Ford band at 9850 - 10200 Angstrons by means of the fit of synthetic spectra to the observations of M stars, employing recent model atmospheres. On the basis of the spectrum synthesis, we analyze the dependence of the band upon atmospheric parameters. FeH lines are a very sensitive surface gravity indicator, being stronger in dwarfs. They are also sensitive to metallicity (Allard & Hauschildt 1995). The blending with CN lines, which are stronger in giants, does not affect the response of the Wing-Ford band to surface gravity at low resolution (or high velocity dispersions) because CN lines, which are spread all along the spectrum, are smeared out at convolutions of FWHM $\simgreat$ 3 Angstrons. We conclude that the Wing-Ford band is a suitable dwarf/giant indicator for the study of composite stellar populations.

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Ricardo P. Schiavon, B. Barbuy, Patan D. Singh. 1997-01-23. The FeH Wing-Ford Band in Spectra of M Stars. https://doi.org/10.1086/304332

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