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Quantitative spectral analysis of early B-type supergiants in the Sculptor galaxy NGC 300

Miguel Alejandro Urbaneja·Artemio Herrero·Fabio Bresolin·Rolf-Peter Kudritzki·Wolgang Gieren·Joachim Puls
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Abstract

The spectra of two early B-type supergiant stars in the Sculptor spiral galaxy NGC 300 are analysed by means of non-LTE line blanketed unified model atmospheres, aimed at determining their chemical composition and the fundamental stellar and wind parameters. For the first time a detailed chemical abundance pattern (He, C, N, O, Mg and Si) is obtained for a B-type supergiant beyond the Local Group. The derived stellar properties are consistent with those of other Local Group B-type supergiants of similar types and metallicities. One of the stars shows a near solar metallicity while the other one resembles more a SMC B supergiant. The effects of the lower metallicity can be detected in the derived wind momentum.

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Miguel Alejandro Urbaneja, Artemio Herrero, Fabio Bresolin, Rolf-Peter Kudritzki, Wolgang Gieren, Joachim Puls. 2003-01-10. Quantitative spectral analysis of early B-type supergiants in the Sculptor galaxy NGC 300. https://doi.org/10.1086/368406

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