Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2012-01-19
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
12 pages, 10 figures, Accepted for publication in ApJ
Scientific paper
The physical mechanisms that set the initial rotation rates in massive stars are a crucial unknown in current star formation theory. Observations of young, massive stars provide evidence that they form in a similar fashion to their low-mass counterparts. The magnetic coupling between a star and its accretion disk may be sufficient to spin down low-mass pre-main sequence (PMS) stars to well below breakup at the end stage of their formation when the accretion rate is low. However, we show that these magnetic torques are insufficient to spin down massive PMS stars due to their short formation times and high accretion rates. We develop a model for the angular momentum evolution of stars over a wide range in mass, considering both magnetic and gravitational torques. We find that magnetic torques are unable to spin down either low or high mass stars during the main accretion phase, and that massive stars cannot be spun down significantly by magnetic torques during the end stage of their formation either. Spin-down occurs only if massive stars' disk lifetimes are substantially longer or their magnetic fields are much stronger than current observations suggest.
Krumholz Mark R.
Ramirez-Ruiz Enrico
Rosen Anna L.
No associations
LandOfFree
What Sets the Initial Rotation Rates of Massive Stars? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with What Sets the Initial Rotation Rates of Massive Stars?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and What Sets the Initial Rotation Rates of Massive Stars? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-320063