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Resolviendo el fondo de rayos X duro extragaláctico
Nature
|April 13, 2000
Resumen
Los investigadores han identificado las fuentes del fondo duro de rayos X, un misterio cósmico durante décadas. Las observaciones de Deep Chandra revelan que estas fuentes coinciden con el fondo.
Área de la Ciencia:
- Astronomía cósmica de rayos X de la astronomía cósmica de rayos X.
- La astrofísica es la astrofísica.
- Astrofísica de altas energías de alta energía.
Sus antecedentes:
- El origen del fondo duro de rayos X (2-10 keV) permanece sin explicación durante más de 35 años.
- Si bien se identifican fuentes de fondo suaves de rayos X (principalmente cuásares), su distribución de energía espectral no coincide con el espectro de fondo general.
Objetivo del estudio:
- Para investigar y resolver el misterio del origen del fondo de rayos X duro.
- Identificar las fuentes que contribuyen al fondo duro de rayos X y analizar sus propiedades.
Principales métodos:
- Utilizó el satélite Chandra para un profundo estudio de rayos X.
- Analizó la distribución de energía espectral de las fuentes de rayos X duros detectadas.
Principales resultados:
- Las fuentes de rayos X duros detectadas representan al menos el 75% del fondo de rayos X duros.
- La distribución de energía espectral promedio de estas fuentes coincide estrechamente con el espectro de fondo.
- Las fuentes identificadas están asociadas con núcleos de galaxias brillantes u objetos ópticamente débiles, núcleos galácticos potencialmente activos o quásares de alto desplazamiento al rojo.
Conclusiones:
- El estudio resuelve significativamente el misterio de larga data del fondo duro de rayos X.
- Fuentes identificadas proporcionan una fuerte explicación para el espectro de fondo de rayos X duro observado.
- Los hallazgos sugieren una contribución significativa de núcleos galácticos activos, posiblemente oscurecidos, o cuásares distantes.
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