Quantitative Spectroscopy of 24 A supergiants in the Sculptor galaxy NGC 3001: Flux weighted gravity luminosity relationship, metallicity and metallicity gradient
نویسندگان
چکیده
A quantitative spectral analysis of 24 A supergiants in the Sculptor Group spiral galaxy NGC 300 at a distance of 1.9 Mpc is presented. A new method is introduced to analyze low resolution (∼ 5Å) spectra, which yields metallicities accurate to 0.2 dex including the uncertainties arising from the errors in Teff (5%) and log g (0.2 dex). For the first time the stellar metallicity gradient based on elements such as titanium 1Based on VLT observations for ESO Large Programme 171.D-0004.
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Extragalactic Stellar Astronomy with the Brightest Stars in the Universe
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