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La formación y fragmentación de discos alrededor de protoestrellas primordiales
Paul C Clark1, Simon C O Glover, Rowan J Smith
1Institut für Theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany. pcc@ita.uni-heidelberg.de
Science (New York, N.Y.)
|February 5, 2011
Resumen
Las primeras estrellas en el universo a menudo formaban parte de sistemas múltiples cercanos, no solitarios como se creía anteriormente. La fragmentación gravitacional de sus discos probablemente formó estos primeros sistemas estelares binarios y de orden superior.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Cosmología Cosmología.
- Evolución Estelar Evolución Estelar
Sus antecedentes:
- La formación de las primeras estrellas marcó el final de las edades oscuras cósmicas.
- Los modelos anteriores sugirieron que estas estrellas masivas se formaron de forma solitaria o en amplios sistemas binarios dentro de minihalos de materia oscura.
- La naturaleza de la formación estelar temprana influyó significativamente en la evolución posterior del universo.
Objetivo del estudio:
- Para investigar la multiplicidad de las primeras estrellas formadas en el universo.
- Desafiar la noción prevaleciente de la formación solitaria de la primera estrella.
- Comprender los mecanismos que rigen la formación de los primeros sistemas estelares.
Principales métodos:
- Simulaciones numéricas de la formación estelar temprana dentro de los minihalos de materia oscura.
- Análisis de los procesos de fragmentación gravitacional en los discos protostellares.
- Modelado de la formación de sistemas binarios y de orden superior.
Principales resultados:
- Las simulaciones indican que las primeras estrellas se formaron con frecuencia en sistemas múltiples estrechos.
- Los discos protoestelares alrededor de estas primeras estrellas eran gravitacionalmente inestables.
- Esta inestabilidad condujo a la fragmentación, produciendo sistemas binarios y de orden superior estrechamente empacados.
Conclusiones:
- Las primeras estrellas eran comúnmente miembros de sistemas estelares múltiples, al contrario de las suposiciones anteriores.
- La fragmentación gravitacional de los discos de acreción fue un mecanismo clave para la formación de estos primeros sistemas múltiples.
- Estos hallazgos cambian nuestra comprensión de la formación y evolución de las primeras estructuras cósmicas.
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