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Reflexión del régimen de gravedad fuerte en un cuásar con lente en el corrimiento al rojo z = 0,6588
R C Reis1, M T Reynolds1, J M Miller1
1Department of Astronomy, University of Michigan, Ann Arbor, Michigan 48109, USA.
Nature
|March 7, 2014
Resumen
Los agujeros negros supermasivos crecen coherentemente, no caóticamente, en desplazamientos al rojo moderados. Este estudio midió una alta rotación del agujero negro a z = 0.658 utilizando la reflexión relativista, lo que indica un crecimiento sostenido de la acreción.
Área de la Ciencia:
- Astrofísica y Cosmología.
- Física del agujero negro Física del agujero negro
- Evolución de la galaxia Evolución de la galaxia.
Sus antecedentes:
- La rotación de los agujeros negros supermasivos (SMBH) es un indicador clave de su coevolución con las galaxias anfitrionas.
- Se cree que las pequeñas y medianas empresas crecen a través de la acreción impulsada por las fusiones a altos desplazamientos al rojo (z > 2), lo que lleva a un alto giro.
- El modo de acreción (coherente vs. caótico) de SMBHs en desplazamientos al rojo moderados (z < 1) sigue siendo poco conocido.
Objetivo del estudio:
- Investigar el historial de acreción de una SMBH de desplazamiento hacia el rojo moderado mediante la medición de su giro.
- Para determinar si las SMBHs en z ~ 0.5-1 crecen principalmente a través de una acreción coherente o caótica.
Principales métodos:
- Análisis de datos de rayos X de archivo combinado con una observación profunda de un cuásar con lente gravitacional en z = 0.658.
- Medición del espín SMBH a través del estudio de las características de reflexión relativistas del disco de acreción interno.
- Utilizando lentes gravitacionales para superar las limitaciones de distancia para detectar señales de débil reflexión.
Principales resultados:
- Detección de rasgos de reflexión relativista originados dentro de tres radios gravitacionales del agujero negro.
- Determinación de un parámetro de espín de agujero negro alto, a = 0.87(+0.08)(-0.15) a 3σ de confianza, y a > 0.66 a 5σ.
- El alto giro medido sugiere fuertemente el crecimiento a través de episodios de acreción coherentes.
Conclusiones:
- El SMBH en el cuásar con lente exhibe un alto giro, consistente con el crecimiento a través de la acreción coherente.
- Este hallazgo implica que el crecimiento de SMBH en desplazamientos hacia el rojo moderados (0.5 ≤ z ≤ 1) está predominantemente impulsado por una acreción coherente.
- El estudio proporciona la primera detección significativa de la reflexión relativista en un cuásar de desplazamiento al rojo moderado, lo que permite mediciones de espín.
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