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El brillante destello óptico y el resplandor de la explosión de rayos gamma GRB 130427A
W T Vestrand1, J A Wren, A Panaitescu
1Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA.
Science (New York, N.Y.)
|November 23, 2013
Resumen
Los brillantes destellos ópticos de las explosiones de rayos gamma (GRB) se correlacionan con las emisiones de rayos gamma de alta energía. Esto sugiere que la emisión de choque inverso explica los primeros resplandores posteriores de GRB, ofreciendo información sobre las explosiones de colapso estelar.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- Astrofísica de altas energías de alta energía.
- La cosmología observacional.
Sus antecedentes:
- Las explosiones de rayos gamma (GRB) son poderosas explosiones cósmicas resultantes del colapso masivo de estrellas.
- Las emisiones simultáneas de rayos ópticos y gamma ofrecen información crucial sobre la física de los GRB.
- Comprender los sistemas progenitor y los mecanismos de emisión de los GRB es un objetivo clave en astrofísica.
Objetivo del estudio:
- Para investigar la relación entre los destellos ópticos y las emisiones de rayos gamma del GRB 130427A.
- Para determinar los mecanismos de emisión responsables de las señales ópticas y de rayos gamma observadas.
- Identificar las condiciones óptimas para estudiar la emisión de rayos gamma de alta energía de los GRB.
Principales métodos:
- Observación del destello óptico y el resplandor de GRB 130427A.
- Análisis de la correlación temporal entre el flujo óptico y el flujo de rayos gamma de >100 MeV.
- Modelado de los procesos de emisión de choques (choques hacia adelante y hacia atrás) en eyecciones relativistas.
Principales resultados:
- Se observó una fuerte correlación entre el flujo óptico y el flujo de rayos gamma de >100 MeV en los primeros 7000 segundos.
- Esta correlación se explica mejor por la emisión de choque inverso de las eyecciones relativistas que impactan con el material circundante.
- Las emisiones ópticas posteriores se atribuyeron a un choque hacia adelante que se propagaba a través del entorno circumburst.
Conclusiones:
- El estudio vincula los resplandores ópticos con la emisión de rayos gamma de >100 MeV, apoyando los modelos de choque.
- Los resplandores ópticos cercanos, de pico temprano, se identifican como objetivos principales para el estudio de la emisión de rayos gamma gigaelectron volt a teraelectron volt.
- Esta investigación mejora nuestra comprensión de la física que rige las explosiones de rayos gamma y sus fenómenos asociados.
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