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Una inestabilidad de acreción compartida para agujeros negros y estrellas de neutrones
F M Vincentelli1,2,3,4, J Neilsen5, A J Tetarenko6
1Instituto de Astrofísica de Canarias, La Laguna, Tenerife, Spain. fvincentelli@iac.es.
Nature
|March 1, 2023
Resumen
Las estrellas de neutrones en acrecentamiento exhiben una inestabilidad de múltiples longitudes de onda previamente vista solo en los agujeros negros. Esta inestabilidad explica la rápida variabilidad en la acumulación de objetos compactos y las eyecciones relativistas.
Área de la Ciencia:
- La astrofísica
- Astrofísica de alta energía
- Acreción de objetos compactos
Sus antecedentes:
- Se teoriza que los discos de acreción alrededor de objetos compactos se vuelven inestables a altas luminosidades.
- Esta inestabilidad, impulsada por la presión de la radiación, causa el agotamiento cíclico y la reposición del disco interno.
- La verificación cuantitativa anterior se limitaba a un solo agujero negro de masa estelar.
Objetivo del estudio:
- Para investigar la presencia de una inestabilidad conocida de múltiples longitudes de onda en estrellas de neutrones en acreción.
- Para explicar la variabilidad observada a través del espectro electromagnético en objetos compactos de acrecentamiento brillante.
- Identificar los componentes físicos responsables de la variabilidad rápida de las longitudes de onda múltiples.
Principales métodos:
- Astronomía de las observaciones
- Análisis de datos de varias longitudes de onda (de radio a rayos X)
- Estudio comparativo de acreción de estrellas de neutrones y agujeros negros
Principales resultados:
- La misma inestabilidad de múltiples longitudes de onda observada en los agujeros negros se detectó alrededor de una estrella de neutrones en acrecentamiento.
- La inestabilidad explica consistentemente la variabilidad espectral tanto de los agujeros negros como de las estrellas de neutrones a altas tasas de acreción.
- El modelo tiene en cuenta las eyecciones relativistas durante las transiciones de agotamiento/rellenado del disco interno.
Conclusiones:
- Los discos de acreción alrededor de las estrellas de neutrones están sujetos a la misma inestabilidad que los alrededor de los agujeros negros.
- Esta inestabilidad es un factor clave de la variabilidad rápida y de múltiples longitudes de onda en objetos compactos de alta acreción.
- Los hallazgos proporcionan una explicación unificada del comportamiento de estos sistemas e identifican los componentes físicos responsables.
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