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The formation of massive star systems by accretion
Mark R Krumholz1, Richard I Klein, Christopher F McKee
1Department of Astronomy, University of California, Santa Cruz, CA95064, USA. krumholz@ucolick.org
Science (New York, N.Y.)
|January 20, 2009
Summary
Radiation pressure from massive stars does not stop accretion. Instead, instabilities channel gas, allowing stars to grow and form multiple systems, challenging previous theories of stellar mass limits.
Area of Science:
- Astrophysics
- Computational astrophysics
Background:
- Massive stars are theorized to have accretion limited by radiation pressure exceeding gravitational attraction.
- Previous models predicted radiation pressure would halt the growth of massive stars.
Purpose of the Study:
- To investigate the role of radiation pressure in the accretion process of massive stars.
- To determine if radiation pressure limits stellar mass accumulation.
Main Methods:
- Three-dimensional radiation-hydrodynamic simulations.
- Modeling the collapse of a massive prestellar core.
Main Results:
- Radiation pressure does not halt accretion onto massive stars.
- Gravitational and Rayleigh-Taylor instabilities channel gas via self-shielding disks and filaments.
- Simulations show disk fragmentation leading to the formation of massive companions.
Conclusions:
- Radiation pressure is not the primary limiter of massive star accretion.
- Instabilities facilitate continued accretion, leading to the formation of multiple stellar systems.
- Stellar mass is not limited by radiation pressure due to instability-driven accretion.
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