The spatial distribution of galaxies within the CMB cold spot in the Corona Borealis supercluster

Abstract

We study the spatial distribution and colours of galaxies within the region covered by the cold spot in the cosmic microwave background (CMB) recently detected by the Very Small Array (VSA; Genova-Santos et al. 2005, 2008) towards the Corona Borealis supercluster (CrB-SC). The spot is in the northern part of a region with a radius ~1 degree (~5 Mpc at the redshift of CrB-SC) enclosing the clusters Abell 2056, 2065, 2059 and 2073, and where the density of galaxies, excluding the contribution from those clusters, is ~2 times higher than the mean value in typical intercluster regions of the CrB-SC. Two of such clusters (Abell 2056 and 2065) are members of the CrB-SC, while the other two are in the background. This high density intercluster region is quite inhomogeneous, being the most remarkable feature a large concentration of galaxies in a narrow filament running from Abell 2065 with a length of ~35 arcmin (~3 Mpc at the redshift of CrB-SC) in the SW-NE direction. This intercluster population of galaxies probably results from the interaction of clusters Abell 2065 and 2056. The area subtended by the VSA cold spot shows an excess of faint (21<r<22) and red (1.1<r-i<1.3) galaxies as compared with typical values within the CrB-SC intercluster regions. This overdensity of galaxies shows a radial dependence and extends out to ~15 arcmin. This could be signature of a previously unnoticed cluster in the background.

Accepted for publication in MNRAS

References in corpus (4)

• A MaxBCG Catalog of 13,823 Galaxy Clusters from the Sloan Digital Sky Survey
• Observations of the Corona Borealis supercluster with the superextended Very Small Array: further constraints on the nature of the non-Gaussian CMB cold spot
• Non-Gaussianity in the Very Small Array CMB maps with Smooth-Goodness-of-fit tests
• Millimetric observation of the SZ effect in the Corona Borealis supercluster

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• Some statistical remarks on the Giant GRB Ring
• The Corona Borealis supercluster: connectivity, collapse, and evolution
• The Sunyaev-Zeldovich effect in superclusters of galaxies using gasdynamical simulations: the case of Corona Borealis
• Constraints on the Sunyaev-Zel'dovich signal from the Warm Hot Intergalactic Medium from WMAP and SPT data
• A study of the galaxy redshift distribution toward the cosmic microwave background cold spot in the Corona Borealis supercluster