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Super-resolution Imaging of the Bacterial Division Machinery
Published on: January 21, 2013
Una medición de la densidad de masa cosmológica de la agrupación en el 2dF Galaxy Redshift Survey
J A Peacock1, S Cole, P Norberg
1Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK. jap@roe.ac.uk
Nature
|March 10, 2001
Resumen
Los supercúmulos de galaxias causan la caída de las galaxias, influyendo en la estructura a gran escala. Este estudio midió con precisión el agrupamiento de galaxias utilizando la encuesta 2dF, obteniendo un parámetro cosmológico clave (beta).
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Formación de galaxias Formación de galaxias
Sus antecedentes:
- La formación de estructuras a gran escala se atribuye a la inestabilidad gravitacional de las fluctuaciones iniciales de densidad.
- Se predice que la formación de supercúmulos inducirá la caída de galaxias, causando anisotropías de velocidad observables.
Objetivo del estudio:
- Para medir con precisión el agrupamiento de galaxias y probar la hipótesis de inestabilidad gravitacional.
- Para determinar el parámetro cosmológico beta (Ω^0.6/b) e inferir la densidad del Universo.
Principales métodos:
- Utilizó datos de desplazamiento al rojo de más de 141.000 galaxias de la Encuesta de desplazamiento al rojo de galaxias 2dF.
- Analizó patrones de velocidad recesiva para detectar la anisotropía en el agrupamiento espacial de galaxias.
Principales resultados:
- Determinado el parámetro beta = Ω^0.6/b = 0.43 ± 0.07.
- Cuantificó el sesgo (b) entre el agrupamiento luminoso y el agrupamiento de masa total.
Conclusiones:
- Los resultados favorecen un Universo de baja densidad con Ω aproximadamente 0.3.3.
- Los hallazgos apoyan el modelo de inestabilidad gravitacional para la formación de estructuras cósmicas.
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