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Spectroscopic analysis of new-born massive stars in SMC N 81

Published online by Cambridge University Press:  26 May 2016

Fabrice Martins
Affiliation:
Laboratoire d'Astrophysique, Observatoire Midi-Pyrénées, 14 Avenue Edouard Belin, F-31400 Toulouse, la France
Daniel Schaerer
Affiliation:
Laboratoire d'Astrophysique, Observatoire Midi-Pyrénées, 14 Avenue Edouard Belin, F-31400 Toulouse, la France
Mohammad Heydari-Malayeri
Affiliation:
Laboratoire d'Etudes du Rayonnement et de la Matière en Astrophysique, Observatoire de Paris, 61 Avenue de l'Observatoire, F-75014 Paris, la France

Abstract

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We present the first results of a spectroscopic study of young massive stars in the SMC high excitation blob N 81. These stars have Mv values which are ~ 2 mag smaller than those of normal dwarf stars. Their UV HST-stis spectra reveal features typical of O-type stars, but surprisingly weak wind components. The preliminary modeling of these spectra with the code cmfgen (Hillier & Miller 1998) indicates mass loss rates of the order of 10–9 M yr–1. 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.

Type
Part 3. Location and Distribution of Massive Stars
Copyright
Copyright © Astronomical Society of the Pacific 2003 

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