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Detección del tamaño intrínseco de Sagitario A* a través de imágenes de amplitud de cierre
Geoffrey C Bower1, Heino Falcke, Robeson M Herrnstein
1Astronomy Department and Radio Astronomy Laboratory, University of California, Berkeley, CA 94720, USA. gbower@astro.berkeley.edu
Science (New York, N.Y.)
|April 3, 2004
Resumen
Los investigadores midieron el tamaño de Sagitario A*, el agujero negro supermasivo en el centro de nuestra galaxia. Esta emisión de radio se origina muy cerca del horizonte de eventos del agujero negro, proporcionando nuevos conocimientos sobre sus propiedades.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- La radioastronomía es una radioastronomía.
Sus antecedentes:
- Sagitario A* es el agujero negro supermasivo en el centro de la galaxia de la Vía Láctea.
- Comprender el entorno inmediato de los agujeros negros supermasivos es crucial para probar la relatividad general y las teorías de acreción.
Objetivo del estudio:
- Para determinar el tamaño intrínseco de Sagitario A* en longitudes de onda milimétricas.
- Para sondear la región muy cerca del horizonte de eventos de Sagitario A*.
Principales métodos:
- Utilizó el Very Long Baseline Array (VLBA) para observaciones de radio de alta resolución.
- Observaciones realizadas a una longitud de onda de 7 milímetros.
Principales resultados:
- El tamaño intrínseco de Sagitario A* se midió en 24 +/- 2 radios de Schwarzschild a una longitud de onda de 7 milímetros.
- Se detectó un aumento significativo en el tamaño de la fuente intrínseca (60(-17)(+25)%) en una época de observación.
- Se estableció un límite inferior para la densidad de masa de Sagitario A* a 1,4 x 10^4 masas solares por unidad astronómica cúbica.
Conclusiones:
- La emisión de radio de onda corta de Sagitario A* se origina muy cerca del horizonte de eventos.
- Las variaciones de tamaño observadas pueden proporcionar pistas sobre los procesos de acreción cerca del agujero negro.
- Estos hallazgos limitan los modelos de la física y los entornos de los agujeros negros.
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