Open AccessQuasar environment in the context of large‐scale structure at z ∼0.3
Author(s) -
Söchting Ilona K.,
Clowes Roger G.,
Campusano Luis E.
Publication year - 2002
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2002.05123.x
Subject(s) - quasar , physics , astrophysics , galaxy cluster , galaxy , astronomy , context (archaeology) , cluster (spacecraft) , redshift , ovv quasar , galaxy formation and evolution , geography , archaeology , computer science , programming language
We look at quasar environment in the context of large‐scale structure (LSS) – a new approach, giving a more informed interpretation of quasar–galaxy correlations. This paper presents our first results for a sample of z ∼0.3 quasars. We use Voronoi tessellation applied in colour ( B J ‐ R ) slices for the detection of galaxy clusters and the minimal spanning tree (MST) to delineate the large‐scale structure. This new cluster detection method allows us to find reliably galaxy clusters at z <0.3 from SuperCOSMOS measurements of UK Schmidt Telescope plates. By reconstructing the large‐scale structure in a relatively narrow redshift band (0.2< z <0.3) , we show that quasars follow the large‐scale structure traced by galaxy clusters. None of the quasars in our radio‐quiet sample is located in the central area of a galaxy cluster. Two quasars, found in a very rich environment, are actually located between two very close galaxy clusters, consistent with results on z ∼1 quasars, suggesting that cluster mergers may be involved in one of the quasar formation mechanisms.