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arXiv · 0704.1456

Effective temperature vs line-depth ratio for ELODIE spectra. Gravity and rotational velocity effects

K. Biazzo·A. Frasca·S. Catalano·E. Marilli
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Abstract

The dependence on the temperature of photospheric line-depth ratios (LDRs) in the spectral range 6190-6280 A is investigated by using a sample of 174 ELODIE Archive stellar spectra of luminosity class from V to III. The rotational broadening effect on LDRs is also studied. We provide useful calibrations of effective temperature versus LDRs for giant and main sequence stars with 3800<Teff<6000 K and vsini in the range 0-30 km/s. We found that, with the exception of very few line pairs, LDRs, measured at a spectral resolution as high as 42000, depend on vsini and that, by neglecting the rotational broadening effect, one can mistake the Teff determination of 100 K in the worst cases.

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K. Biazzo, A. Frasca, S. Catalano, E. Marilli. 2007-04-11. Effective temperature vs line-depth ratio for ELODIE spectra. Gravity and rotational velocity effects. https://doi.org/10.1002/asna.200710781

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