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Cuásares libres de polvo en el Universo temprano
Linhua Jiang1, Xiaohui Fan, W N Brandt
1Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, Arizona 85721, USA. ljiang@email.arizona.edu
Nature
|March 19, 2010
Resumen
Los quásares del universo temprano carecen de polvo caliente, lo que sugiere que son objetos jóvenes de primera generación. Su abundancia de polvo caliente se correlaciona con el crecimiento del agujero negro, a diferencia de los cuásares más viejos.
Área de la Ciencia:
- La astronomía es la astronomía.
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
Sus antecedentes:
- Los cuásares distantes con desplazamiento al rojo z ~ 6 exhiben propiedades similares a los cuásares de desplazamiento al rojo inferior.
- Esta similitud sugiere objetos evolucionados, lo que contradice la edad cósmica temprana (el 7% de la edad actual).
- Observaciones anteriores observaron que un quásar z~6 carecía de polvo caliente, lo que plantea preguntas sobre las propiedades del polvo de alto desplazamiento al rojo.
Objetivo del estudio:
- Investigar la prevalencia del polvo caliente en z~6 cuásares.
- Determinar si los quásares libres de polvo caliente son exclusivos del universo temprano.
- Comprender la relación entre la abundancia de polvo caliente y la evolución de la masa del agujero negro.
Principales métodos:
- Analizó una muestra de 21 quásares con desplazamiento al rojo z~6.6.
- Se buscó la emisión detectable del polvo caliente.
- Comparando la abundancia de polvo caliente con la masa del agujero negro central.
Principales resultados:
- Descubrió un segundo quásar sin polvo caliente detectable entre los 21 z~6 quásares.
- No se encontraron contrapartes a estos quásares calientes y libres de polvo a bajo desplazamiento al rojo.
- Demostró que la abundancia de polvo caliente en z~6 quásares se correlaciona con el crecimiento de masa del agujero negro, a diferencia de un desplazamiento al rojo bajo.
Conclusiones:
- z~6 quásares representan una etapa evolutiva temprana con una rápida acreción y formación de polvo.
- Los dos cuásares observados libres de polvo caliente son probablemente objetos de primera generación.
- Estos quásares jóvenes se originaron en entornos libres de polvo y aún no han formado un polvo caliente significativo.
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