Westerlund 1 as a Template for Massive Star Evolution
Abstract
With a dynamical mass M_dyn ~ 1.3x10e5 M_sun and a lower limit M_cl>5x10e4 M_sun from star counts, Westerlund 1 is the most massive young open cluster known in the Galaxy and thus the perfect laboratory to study massive star evolution. We have developed a comprehensive spectral classification scheme for supergiants based on features in the 6000-9000A range, which allows us to identify >30 very luminous supergiants in Westerlund 1 and ~100 other less evolved massive stars, which join the large population of Wolf-Rayet stars already known. Though detailed studies of these stars are still pending, preliminary rough estimates suggest that the stars we see are evolving to the red part of the HR diagram at approximately constant luminosity.
Keywords
Cite
@article{arxiv.0802.4168,
title = {Westerlund 1 as a Template for Massive Star Evolution},
author = {Ignacio Negueruela and J. Simon Clark and Paul A. Crowther and Lucy Hadfield},
journal= {arXiv preprint arXiv:0802.4168},
year = {2009}
}
Comments
To be published in Proceedings of IAU Symposium 250: Massive Stars as Cosmic Engines, held in Kaua'i (Hawaii, USA), Dec 2007, edited by F. Bresolin, P.A. Crowther & J. Puls (Cambridge University Press)