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Una población de galaxias rojas masivas ~ 600 millones de años después del Big Bang
Ivo Labbé1, Pieter van Dokkum2, Erica Nelson3
1Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Melbourne, Victoria, Australia. ilabbe@swin.edu.au.
Nature
|February 22, 2023
Resumen
Los astrónomos descubrieron seis galaxias masivas candidatas, algunas potencialmente alcanzando 1011 masas solares, dentro de los primeros 750 millones de años después del Big Bang usando el Telescopio Espacial James Webb. Este hallazgo sugiere una mayor densidad de masa estelar en las primeras galaxias de lo que se pensaba anteriormente.
Área de la Ciencia:
- Cosmología
- Formación y evolución de las galaxias
- Astronomía de las observaciones
Sus antecedentes:
- Se han identificado galaxias masivas (masas estelares ~1011 masas solares) hasta el desplazamiento al rojo z ~ 6 (aprox. 1 mil millones de años después del Big Bang).
- La identificación de galaxias masivas en épocas cósmicas anteriores es un desafío debido a que la ruptura de Balmer se desplaza a longitudes de onda infrarrojas (> 2,5 μm).
Objetivo del estudio:
- Para buscar galaxias intrínsecamente rojas y masivas en el universo temprano (primeros ~ 750 millones de años).
- Para aprovechar la cobertura de longitud de onda de 1-5 μm del Telescopio Espacial James Webb (JWST) para esta búsqueda.
Principales métodos:
- Utilizó observaciones de liberación temprana del Telescopio Espacial James Webb.
- Enfocado en el rango de longitud de onda de 1-5 μm para capturar la rotura de Balmer desplazada hacia el rojo.
- Buscado galaxias masivas candidatas dentro de un área de estudio específica.
Principales resultados:
- Se identificaron seis galaxias masivas candidatas (masa estelar > 10 masas solares) con desplazamientos al rojo de 7.4 ≤ z ≤ 9.1 (aprox. 500-700 millones de años después del Big Bang).
- Una galaxia candidata muestra una masa estelar potencial de ~1011 masas solares.
- Estos hallazgos se basan en la cobertura espectral de 1-5 μm del JWST.
Conclusiones:
- La existencia de estas galaxias masivas sugiere una densidad de masa estelar significativamente mayor en las primeras galaxias de lo estimado anteriormente.
- Estos resultados desafían los modelos existentes de formación y evolución de las primeras galaxias.
- Se requiere verificación espectroscópica para confirmar las masas estelares y los desplazamientos al rojo de estos candidatos.
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