English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/3977
Compartir / Impacto:
Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL

Cluster of galaxies around seven radio-loud QSOs at 1<z<1.6: K-band images

AutorSánchez, Sebastián F. ; González-Serrano, José Ignacio
Palabras claveGalaxies: clusters: general
Quasars: general
Fecha de publicación18-sep-2002
EditorEDP Sciences
Astron. Astrophys. 396 (2002) 773-786
ResumenWe have conducted a NIR study of the environments of seven radio-loud quasars at redshifts 1<z<1.6. In present paper we describe deep $K$ band images obtained for the fields of ~6X6 arcmin around the quasars with 3$\sigma$ limiting magnitudes of K~20.5. These fields were previously studied using deep B and R band images (Sanchez & Gonzalez-Serrano 1999). Using together optical and NIR data, it has been found a significant excess of galaxies which optical-NIR colours, luminosity, spatial scale, and number of galaxies are compatible with clusters at the redshift of the quasar.
We have selected a sample of cluster candidates analyzing the R-K vs. K diagram. A ~25% of the candidates present red optical-NIR colours and an ultraviolet excess. This population has been also found in clusters around quasars at the same redshifts (Tanaka et al. 2000; Haines et al. 2001). These galaxies seem to follow a mixed evolution: a main passive evolution plus late starformation processes. The quasars do not inhabit the core of the clusters, being found in the outer regions. This result agrees with the hypothesis that the origin/feeding mechanism of the nuclear activity were merging processes. The quasars inhabit the region were a collision is most probably to produce a merger.
Descripción15 pages. Accepted for publishing in A&A.
Aparece en las colecciones: (IFCA) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
0209355v1.pdf923,41 kBAdobe PDFVista previa
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.