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La formación de sistemas estelares masivos por acreción
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
Resumen
La presión de radiación de las estrellas masivas no detiene la acreción. En cambio, las inestabilidades canalizan el gas, permitiendo que las estrellas crezcan y formen múltiples sistemas, desafiando las teorías anteriores de los límites de masa estelar.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- La astrofísica computacional es una astrofísica computacional.
Sus antecedentes:
- Se teoriza que las estrellas masivas tienen una acreción limitada por la presión de radiación que excede la atracción gravitatoria.
- Los modelos anteriores predijeron que la presión de radiación detendría el crecimiento de las estrellas masivas.
Objetivo del estudio:
- Para investigar el papel de la presión de radiación en el proceso de acreción de estrellas masivas.
- Para determinar si la presión de radiación limita la acumulación de masa estelar.
Principales métodos:
- Simulaciones tridimensionales de radiación e hidrodinámica. simulaciones tridimensionales de radiación e hidrodinámica. simulaciones tridimensionales de radiación y hidrodinámica. simulaciones tridimensionales de radiación y hidrodinámica. simulaciones tridimensionales de radiación y hidrodinámica. simulaciones tridimensionales de radiación y hidrodinámica. simulaciones tridimensionales de radiación y hidrodinámica.
- Modelado el colapso de un núcleo prestellar masivo.
Principales resultados:
- La presión de radiación no detiene la acreción en las estrellas masivas.
- Las inestabilidades gravitacionales y de Rayleigh-Taylor canalizan el gas a través de discos y filamentos de auto blindaje.
- Las simulaciones muestran la fragmentación del disco que conduce a la formación de compañeras masivas.
Conclusiones:
- La presión de radiación no es el principal limitador de la acreción de estrellas masivas.
- Las inestabilidades facilitan la acreción continua, lo que lleva a la formación de múltiples sistemas estelares.
- La masa estelar no está limitada por la presión de radiación debido a la acreción impulsada por la inestabilidad.
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