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Un mapa de intensidad de la emisión de hidrógeno de 21 cm en el corrimiento al rojo z, aproximadamente 0,8
Tzu-Ching Chang1, Ue-Li Pen, Kevin Bandura
1IAA, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan. tchang@cita.utoronto.ca
Nature
|July 24, 2010
Resumen
Los astrónomos detectaron el brillo agregado de 21 cm del hidrógeno neutro en la red cósmica a desplazamientos al rojo hasta 1.12. Este avance permite nuevos estudios de la energía oscura utilizando el mapeo de intensidad de 21 cm.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- La radioastronomía es una radioastronomía.
Sus antecedentes:
- La emisión de radio de 21 cm de las sondas de hidrógeno neutro detecta la energía oscura cósmica.
- La cosmología óptica enfrenta desafíos en los desplazamientos al rojo z ~ 1 debido a la opacidad infrarroja atmosférica.
- Las detecciones anteriores de emisiones de 21 cm se limitaron a z = 0.24.
Objetivo del estudio:
- Para desarrollar un campo tridimensional de intensidad de 21 cm en desplazamientos al rojo z = 0,53 a 1,12.
- Para investigar el potencial de la cartografía de intensidad de 21 cm para estudios de energía oscura.
- Para superar las limitaciones de la detección de galaxias individuales en desplazamientos al rojo más altos.
Principales métodos:
- Co-adición de la emisión de hidrógeno neutro (H i) de aproximadamente 10.000 galaxias.
- Utilizando datos del estudio de desplazamiento al rojo de la galaxia óptica DEEP2.
- Medición de la emisión agregada de galaxias no resueltas en la red cósmica.
Principales resultados:
- Se generó con éxito un campo tridimensional de intensidad de 21 cm para z = 0.53 a 1.12.
- El brillo agregado de 21 cm del hidrógeno neutro se detectó con una significación de aproximadamente 4 sigma.
- Ha demostrado la viabilidad del mapeo de intensidad de 21 cm para estudios cosmológicos.
Conclusiones:
- La emisión agregada de 21 cm es una sonda viable de energía oscura en desplazamientos al rojo más altos.
- Esta técnica supera las limitaciones de la cosmología óptica en rangos específicos de corrimiento al rojo.
- Abre nuevas vías para mapear la red cósmica y comprender la aceleración cósmica.
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