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La formación de los sistemas binarios de Población III a partir de las condiciones iniciales cosmológicas
Matthew J Turk1, Tom Abel, Brian O'Shea
1Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 2575 Sand Hill Road, Menlo Park, CA 94025, USA. mturk@slac.stanford.edu
Science (New York, N.Y.)
|July 11, 2009
Resumen
Es posible que las primeras estrellas no se hayan formado de forma aislada. Una simulación cosmológica muestra un cúmulo masivo de gas fragmentándose en dos núcleos, probablemente formando un sistema estelar binario en el universo temprano.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Formación Estelar Formación Estelar.
Sus antecedentes:
- Simulaciones anteriores predijeron primeras estrellas masivas y aisladas.
- Las condiciones del universo temprano son cruciales para entender la formación de estrellas.
Objetivo del estudio:
- Para investigar la fragmentación de las primeras nubes de gas de formación estelar.
- Para determinar si los sistemas estelares binarios podrían formarse a partir de las primeras estrellas.
Principales métodos:
- Simulación cosmológica de alta resolución.
- Análisis de la fragmentación y acreción de la masa de gas.
Principales resultados:
- Un cúmulo de 50 masas solares (M) se fragmentó en dos núcleos con una proporción de masa de 2:1.
- Un núcleo colapsó a altas densidades, mientras que el segundo se enfrió a través de la emisión inducida por la colisión.
- Ambos núcleos acumulan gas y se predice que formarán un sistema estelar binario.
Conclusiones:
- Las primeras estrellas pueden haberse formado en sistemas binarios, desafiando las predicciones anteriores.
- La fragmentación de nubes masivas de gas es una vía viable para la formación temprana de estrellas binarias.
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