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La disección de gas emisor de rayos X alrededor del centro de nuestra galaxia
Q D Wang1, M A Nowak, S B Markoff
1Institute of Astronomy, University of Cambridge, Cambridge, UK. wqd@astro.umass.edu
Science (New York, N.Y.)
|August 31, 2013
Resumen
El agujero negro supermasivo de nuestra galaxia (SMBH) muestra una emisión de rayos X quieta, distinta de los típicos SMBH de baja acreción. Las observaciones descartan estrellas activas y sugieren un flujo de salida de su flujo de acreción.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- Astrofísica de altas energías de alta energía.
- Física de los agujeros negros.
Sus antecedentes:
- La mayoría de los agujeros negros supermasivos (SMBH) exhiben bajos niveles de acreción, lo que los hace difíciles de estudiar.
- SMBH de la Vía Láctea ofrece una oportunidad única para observar la emisión de rayos X en reposo.
Objetivo del estudio:
- Para presentar un análisis detallado de la inmóvil emisión de rayos X de SMBH de nuestra galaxia.
- Investigar el origen de esta emisión y sus implicaciones para los estados de acreción.
Principales métodos:
- Utilizó 3 megasegundos de datos del Observatorio de rayos X Chandra.
- Analizó la distribución espacial y las propiedades espectrales de la emisión de rayos X.
- Buscado líneas espectrales específicas, como el hierro (Fe) Kα, para identificar fuentes de emisión.
Principales resultados:
- La emisión de rayos X es alargada y se alinea con un disco estelar circundante.
- Las estrellas coronalmente activas de baja masa fueron descartadas como la fuente debido a la ausencia de la emisión prevista de hierro (Fe) Kα.
- Una línea Fe Kα extremadamente débil similar al hidrógeno (H) indica una salida del flujo de acreción del SMBH.
Conclusiones:
- La emisión de rayos X observada no proviene de una población estelar, sino que probablemente se origina en el flujo de acreción del SMBH.
- Los hallazgos proporcionan limitaciones cruciales para los modelos teóricos de estados de acreción radiacionalmente ineficientes en SMBHs.
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