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La estrangulación como el mecanismo principal para detener la formación estelar en las galaxias
Y Peng1, R Maiolino1, R Cochrane2
11] Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge CB3 0HE, UK [2] Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
Nature
|May 15, 2015
Resumen
El apagado de galaxias, el cese de la formación de estrellas, es causado principalmente por estrangulación, donde se corta el suministro de gas. Este proceso toma alrededor de cuatro mil millones de años para las galaxias con masas estelares por debajo de 10-11 masas solares.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Evolución de la galaxia Evolución de la galaxia.
- La astrofísica estelar es la astrofísica estelar.
Sus antecedentes:
- Las galaxias se clasifican como formadoras de estrellas (ricas en gas) o en quiescencia (pobres en gas).
- El mecanismo exacto que impulsa la transición de la formación de estrellas a los estados de quietud sigue siendo una cuestión clave en la astrofísica.
- Los mecanismos de apagado propuestos incluyen la eliminación rápida de gas (salidas / desprendimiento) y la inanición gradual del suministro de gas (estrangulamiento).
Objetivo del estudio:
- Para investigar el mecanismo dominante responsable de apagar la formación de estrellas en las galaxias locales.
- Para determinar la escala de tiempo asociada con el apagado de la galaxia.
- Para analizar el papel de la metalicidad estelar y la edad en la comprensión de la transformación de la galaxia.
Principales métodos:
- Análisis de la metalicidad estelar de 26.000 espectros de galaxias.
- Comparación de edades estelares entre galaxias en reposo y galaxias formadoras de estrellas.
- Concéntrese en las galaxias con masas estelares menores a 10 (11) masas solares.
Principales resultados:
- El análisis de la metalicidad estelar indica fuertemente la estrangulación como el mecanismo de apagado primario.
- La escala de tiempo típica para el apagado a través de la estrangulación es de aproximadamente cuatro mil millones de años.
- Las diferencias de edad observadas en las galaxias en reposo corroboran la escala de tiempo de apagado de cuatro mil millones de años.
Conclusiones:
- La estrangulación se identifica como el principal impulsor de la formación estelar que se apaga en las galaxias locales de baja masa.
- El estudio proporciona una escala de tiempo robusta para este proceso de enfriamiento.
- Los hallazgos apoyan un corte gradual del suministro de gas como la clave para la transformación de la galaxia.
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