Quantitative Spectral Analysis of Early B-type Supergiants in the Sculptor Galaxy Ngc 300
نویسندگان
چکیده
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. Subject headings: galaxies: individual (NGC 300) — stars: abundances, earlytype, supergiants, fundamental parameters, winds, outflows
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