Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-26T03:25:41.589Z Has data issue: false hasContentIssue false

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

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

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 

References

Crowther, P.A., Hillier, D.J., Evans, C.J., et al. 2002, ApJ 579, 774.Google Scholar
Herrero, A., Puls, J., Villamariz, M.R. 2000, A&A 354, 193.Google Scholar
Heydari-Malayeri, M., Testor, G. 1982, A&A (Letters) 111, L11.Google Scholar
Heydari-Malayeri, M., Rosa, M., Schaerer, D., et al. 2002, A&A 381, 951.Google Scholar
Hillier, D.J., Miller, D.L. 1998, ApJ 496, 407.CrossRefGoogle Scholar
Hillier, D.J., Lanz, T., Heap, S., et al. 2003, ApJ in press.Google Scholar
Kudritzki, R.P., Puls, J. 2000, Ann. Review Astron. Astrophys. 38, 613.Google Scholar
Lamers, H., Cassinelli, J.P. 1996, in: Leitherer, C., Fritze-von Alvensleben, U. & Huchra, J. (eds.), From Stars to Galaxies. The Impact of Stellar Physics on Galaxy Evolution, ASP-CS 98, 162.Google Scholar
Puls, J., Kudritzki, R.-P., Herrero, A., et al. 1996, A&A 305, 171.Google Scholar
Vink, J., de Koter, A., Lamers, H. 2000, A&A 362, 295.Google Scholar
Walborn, N.R., Parker, J.W. 1992, ApJ (Letters) 399, L87.Google Scholar