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Un perfil de absorción centrado en 78 megahertz en el espectro promedio del cielo
Judd D Bowman1, Alan E E Rogers2, Raul A Monsalve1,3,4
1School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287, USA.
Nature
|March 2, 2018
Resumen
Los científicos detectaron una distorsión de la señal de radio de las primeras estrellas que interactúan con el gas de hidrógeno primordial. La señal
Área de la Ciencia:
- Cosmología
- La astrofísica
- La radioastronomía
Sus antecedentes:
- Las primeras estrellas emitieron luz ultravioleta, influyendo en el gas de hidrógeno primordial.
- Se esperaba que esta interacción creara una distorsión espectral de radio observable.
Objetivo del estudio:
- Para detectar y analizar la distorsión espectral causada por las primeras estrellas en el Universo temprano.
- Investigar las discrepancias entre las señales observadas y las predicciones teóricas.
Principales métodos:
- Observación del espectro radioeléctrico promediado en el cielo a frecuencias inferiores a 200 megahertz.
- Análisis de un perfil de absorción detectado centrado en 78 megahertz.
Principales resultados:
- Detección de un perfil de absorción aplanado con características específicas de frecuencia y amplitud.
- La amplitud observada fue significativamente más alta de lo predicho por los modelos astrofísicos estándar.
Conclusiones:
- La discrepancia sugiere un gas primordial más frío o una radiación de fondo más caliente.
- Las interacciones entre materia oscura y bariones son una explicación potencial para la amplitud de la señal observada.
- Evidencia de la formación estelar temprana y el fondo del fotón Lyman-α 180 millones de años después del Big Bang.
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