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La formación de protoestrellas en el universo temprano
Naoki Yoshida1, Kazuyuki Omukai, Lars Hernquist
1Department of Physics, Nagoya University, Furocho, Chikusa, Nagoya, Aichi 464-8602, Japan. nyoshida@a.phys.nagoya-u.ac.jp
Science (New York, N.Y.)
|August 2, 2008
Resumen
Los científicos simularon la formación de las primeras estrellas. Las fluctuaciones de densidad del Big Bang pueden sembrar una pequeña protoestrella, un precursor de las estrellas primordiales masivas.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Evolución Estelar Evolución Estelar
Sus antecedentes:
- La formación y la naturaleza de las primeras estrellas (estrellas de Población III) en el universo primitivo no se comprenden bien.
- El crecimiento de la estructura cósmica se teoriza que ocurre jerárquicamente a través de la inestabilidad gravitacional.
- La evidencia observacional sugiere la existencia de estrellas primordiales masivas en el universo temprano.
Objetivo del estudio:
- Para investigar los mecanismos de formación de las primeras estrellas utilizando simulaciones por computadora ab initio.
- Para modelar los procesos atómicos y moleculares en el gas primordial dentro de un universo en expansión.
Principales métodos:
- Desarrolló una simulación de computadora ab initio.
- Simuló la formación de estrellas primordiales mediante el seguimiento de procesos atómicos y moleculares.
- Incorporó un modelo de universo en expansión.
Principales resultados:
- Las simulaciones muestran que las fluctuaciones de densidad primordial del Big Bang pueden iniciar la formación de estrellas.
- Una pequeña protoestrella, aproximadamente el 1% de la masa del Sol, puede formarse a partir de estas fluctuaciones.
- Esta protoestrella actúa como una semilla para el posterior desarrollo de estrellas primordiales masivas.
Conclusiones:
- Las fluctuaciones de densidad primordial son un mecanismo viable para iniciar la formación de las primeras estrellas.
- La simulación proporciona una vía para comprender el origen de las estrellas masivas en el universo temprano.
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