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La masa de los bariones faltantes en el bosque de rayos X del medio intergaláctico cálido y caliente
Fabrizio Nicastro1, Smita Mathur, Martin Elvis
1Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, Massachusetts 02138, USA. fnicastro@cfa.harvard.edu
Nature
|February 4, 2005
Resumen
Los astrónomos han localizado una población significativa de bariones faltantes en el medio intergaláctico cálido y caliente. Este descubrimiento ayuda a resolver un rompecabezas de larga data en la cosmología con respecto a la materia que falta en el universo.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- El medio intergaláctico es el medio intergaláctico.
Sus antecedentes:
- Las mediciones cosmológicas muestran que los bariones constituyen ~4% de la masa-energía del universo.
- Los recuentos bariónicos en los primeros tiempos (z > 2) coinciden con las predicciones.
- Sin embargo, los recuentos bariónicos cercanos a nuestra época (z < 2) son solo el ~55% de los primeros recuentos, lo que indica que el ~45% están "desaparecidos".
Objetivo del estudio:
- Para determinar la densidad de masa de una población bariónica previamente no detectada.
- Para investigar la fase caliente-caliente del medio intergaláctico como un depósito para los bariones faltantes.
Principales métodos:
- Utilizando recientes mediciones cosmológicas.
- Analizar datos para detectar y cuantificar los bariones en el medio intergaláctico caliente.
Principales resultados:
- Se ha identificado una población de bariones no detectada previamente.
- La densidad de masa determinada de estos bariones es consistente con la densidad esperada de los bariones faltantes.
Conclusiones:
- El cálido y caliente medio intergaláctico probablemente alberga la mayoría de los bariones desaparecidos del universo.
- Este hallazgo reconcilia las discrepancias en el censo bariónico a través del tiempo cósmico.
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