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The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
¿Son algunos lagos BL artefactos de la lente gravitacional?
Nature
|March 1, 1990
Resumen
La lente gravitacional de las estrellas en las galaxias de primer plano puede explicar los objetos BL Lacertae. Este fenómeno amplifica el fondo de quásares variables ópticamente violentos, influyendo en las distribuciones de desplazamiento al rojo observadas en BL Lac.
Área de la Ciencia:
- La astronomía es la astronomía.
- La astrofísica es la astrofísica.
- Cosmología Cosmología.
Sus antecedentes:
- Los objetos BL Lacertae (BL Lacs) son cuásares sin línea.
- Una hipótesis anterior sugirió que los BL Lacs son quásares de variable violenta óptica (OVV) con lente gravitacional.
- Esta hipótesis se basó en las similitudes generales entre los quásares BL Lacs y OVV.
Objetivo del estudio:
- Para investigar la hipótesis de que los BL Lacs son cuásares OVV con lente gravitacional.
- Para explicar la distribución observada de los desplazamientos al rojo BL Lac.
- Para identificar las características de las galaxias que actúan como microlentes.
Principales métodos:
- Análisis de objetos BL Lac observados recientemente.
- Examen de la distribución cósmica espacial de los lagos BL.
- Modelado de los efectos de lente gravitacional de las estrellas en las galaxias de primer plano.
Principales resultados:
- La evidencia sugiere que algunos lagos BL son quásares OVV con lente, con galaxias elípticas en primer plano observadas.
- La distribución de desplazamiento al rojo observada en BL Lac es difícil de explicar sin lente gravitacional.
- Se predice que las galaxias microlentes aparecerán en dos picos de desplazamiento al rojo: 0.05-0.10 y cerca del cuásar distante.
Conclusiones:
- La lente gravitacional de las estrellas en las galaxias de primer plano es una explicación plausible para una fracción significativa de los objetos BL Lac.
- Este mecanismo de lente ayuda a conciliar la distribución de desplazamiento al rojo observada en BL Lac con los modelos cosmológicos.
- El estudio predice rangos específicos de corrimiento al rojo para galaxias que actúan como microlentes.
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