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Spectroscopic analysis of newborn massive stars in SMC N81

F. Martins·D. Schaerer·M. Heydari-Malayeri
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Abstract

We present the first results of a spectroscopic study of young massive stars in the SMC High Excitation Blob N81. These stars have Mv values which are ~ 2 mag smaller than those of nor mal dwarf stars. Their UV STIS spectra reveal features typical of O stars, but surprisingly weak wind components. The preliminary modelling of these spectr a with the code CMFGEN (Hillier & Miller 1998) indicates a mass loss rate of the order 10e-9 Mdot/yr. If confirmed, such a weak wind may indicate either a breakdown of the wind-momentum luminosity relation at low luminosity, or a steeper slope of this relation at low metallicity.

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F. Martins, D. Schaerer, M. Heydari-Malayeri. 2003-01-22. Spectroscopic analysis of newborn massive stars in SMC N81. https://arxiv.org/abs/astro-ph/0301451

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