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Sobre el origen de la anisotropía de la luz de fondo extragaláctica en el infrarrojo cercano
Michael Zemcov1, Joseph Smidt2, Toshiaki Arai3
1Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA. Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109, USA.
Science (New York, N.Y.)
|November 8, 2014
Resumen
Las fluctuaciones de la luz de fondo extragaláctica (EBL) revelan la luz intrahalo (IHL) de estrellas despojadas, no de las primeras galaxias. Este hallazgo sugiere que IHL contribuye significativamente al presupuesto de energía del fotón cósmico.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- La astronomía observacional es la astronomía de las observaciones.
Sus antecedentes:
- La anisotropía de la luz de fondo extragaláctica (EBL) ofrece información sobre la producción de fotones cósmicos y estructuras débiles que se han perdido en las encuestas de galaxias.
- Se debaten las fluctuaciones de EBL infrarrojas, con orígenes propuestos como galaxias primordiales / agujeros negros durante la época de reionización (EOR) o luz intrahalo (IHL) de estrellas despojadas por mareas a bajo corrimiento al rojo.
Objetivo del estudio:
- Para medir la anisotropía de EBL en longitudes de onda infrarrojas utilizando un experimento de cohete de sondeo especializado.
- Para diferenciar entre las fuentes propuestas de las fluctuaciones EBL, específicamente las galaxias EOR / agujeros negros frente a IHL.
Principales métodos:
- Realizó un experimento de cohete de sondeo especializado para medir la anisotropía de EBL a 1.1 y 1.6 micrómetros.
- Analizó las fluctuaciones observadas y comparó su amplitud y características con las predicciones de poblaciones de galaxias conocidas y modelos teóricos.
Principales resultados:
- Las fluctuaciones observadas de EBL exceden significativamente la amplitud esperada de las poblaciones de galaxias conocidas.
- Las fluctuaciones medidas son inconsistentes con las emisiones de galaxias EOR y agujeros negros.
- Los datos apoyan firmemente el IHL como la fuente principal de la anisotropía observada de EBL.
- La intensidad de EBL medida es comparable con el fondo de las galaxias conocidas, lo que indica una contribución sustancial de energía de fotones cósmicos.
Conclusiones:
- La luz intrahalórica (IHL) de las estrellas despojadas por mareas es la fuente dominante de la anisotropía observada de la luz de fondo extragaláctica (EBL) en longitudes de onda infrarrojas.
- Los hallazgos desafían la contribución de las galaxias del universo temprano y los agujeros negros a las fluctuaciones de EBL.
- IHL representa un componente significativo del presupuesto total de energía de fotones cósmicos.
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