A constraint on the angular momentum
evolution of Be stars
I.A. Steele
Astrophysics Research Institute,
Liverpool John Moores University, L41 1LD, UK
The Be star sample of
Steele et al. (1998)
has a distribution of v sin i
that is luminosity dependent, with giants having lower projected
rotational velocities than dwarfs. We show that this effect can be
understood simply in terms of angular momentum conservation during the
evolution from dwarf to giant. Any decretion disk or other angular
momentum losing mechanism for such objects must cause a loss of no
more than 15% of the stellar angular momentum over the Be phase
lifetime.
1999, A&A, 343, 237
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