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Las firmas de gas frío que alimenta una galaxia de formación estelar en el corrimiento al rojo 2.3
N Bouché1, M T Murphy, G G Kacprzak
1CNRS/IRAP, Toulouse, France. nicolas.bouche@irap.omp.eu
Science (New York, N.Y.)
|July 6, 2013
Resumen
Se encontró evidencia directa de que la acreción de gas alimentaba a las galaxias. Las observaciones revelaron distintas firmas cinemáticas del gas en órbita, confirmando su papel en el crecimiento de las galaxias y la formación de estrellas.
Área de la Ciencia:
- La astronomía y la astrofísica.
- Dinámica de los gases cósmicos Dinámica de los gases cósmicos
- Evolución de la galaxia Evolución de la galaxia.
Sus antecedentes:
- Se teoriza que las galaxias crecen a través de una continua acreción de gas intergaláctico.
- La evidencia observacional directa de este proceso de acreción de gas ha sido escasa.
- Se espera que el gas acumulado orbite los halos galácticos, influyendo en la formación estelar y la cinemática de las galaxias.
Objetivo del estudio:
- Proporcionar evidencia observacional directa de la acreción de gas que alimenta galaxias distantes formadoras de estrellas.
- Para investigar las firmas cinemáticas asociadas con el gas acumulado en los halos galácticos.
- Para cuantificar la contribución de la acreción de gas al crecimiento de las galaxias.
Principales métodos:
- Utilizó líneas de visión de cuásares de fondo para sondear el gas que rodea una galaxia distante de formación estelar.
- Analizó la cinemática del gas a una distancia proyectada de 26 kiloparsecs de la galaxia anfitriona.
- Estimó la tasa de acreción de gas basada en datos de observación.
Principales resultados:
- Se detectaron distintas firmas cinemáticas en el medio circumgaláctico, consistentes con el gas acumulado en órbita.
- Confirmó la presencia de gas a distancias significativas (26 kpc) de la galaxia de formación estelar.
- Se encontró que la tasa estimada de acreción de gas era comparable a la tasa de formación estelar de la galaxia.
Conclusiones:
- La acreción de gas contribuye significativamente al crecimiento de las galaxias, suministrando combustible para la formación de estrellas.
- Las firmas cinemáticas observadas proporcionan una fuerte evidencia de la acreción de gas intergaláctico.
- Este estudio ofrece apoyo observacional directo a los modelos teóricos de alimentación y evolución de las galaxias.
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