Shapley Supercluster Survey: Galaxy evolution from filaments to cluster cores

Abstract

We present an overview of a multi-wavelength survey of the Shapley supercluster (SSC; z∼0.05) covering a contiguous area of 260 h (SC 1327-312, SC 1329 showing evidence of cluster-cluster interactions. Optical (ugri) and near-infrared (K) imaging acquired with VST and VISTA allow us to study the galaxy population down to m ⋆ +6 at the supercluster redshift. A dedicated spectroscopic survey with AAOmega on the Anglo-Australian Telescope provides a magnitude-limited sample of supercluster members with 80% completeness at ∼m ⋆ +3. We derive the galaxy density across the whole area, demonstrating that all structures within this area are embedded in a single network of clusters, groups and filaments. The stellar mass density in the core of the SSC is always higher than 9×10 9 M ⊙ Mpc −3 , which is ∼40× the cosmic stellar mass density for galaxies in the local Universe. We find a new filamentary structure (∼7 Mpc long in projection) connecting the SSC core to the cluster A 3559, as well as previously unidentified density peaks. We perform a weak-lensing analysis of the central 1 deg 2 field of the survey obtaining for the central cluster A 3558 a mass of M 500 = 7.63 +3.88 −3.40 × 10 14 M ⊙ , in agreement with X-ray based estimates.

Shapley Supercluster Survey: mapping the filamentary network connecting the clusters

“…The ShaSS (Merluzzi et al 2015) is based on VST optical imaging (Capaccioli & Schipani 2011), acquired within the Italian INAF Guaranteed Time of Observations (PI: P. Merluzzi). The Omega-CAM instrument (Kuijken 2011) on the VST has a corrected field of view of 1 • × 1 • , enabling the whole ShaSS area to be covered with 23 VST fields as shown in Fig.…”

“…ShaSS comprises high-quality optical ugri imaging carried out with OmegaCAM on the 2.6m VLT Survey Telescope (VST) and near-infrared K-band imaging from the 4.1m Visible and Infrared Survey Telescope for Astronomy (VISTA), both taking advantage of the exceptional observing conditions available at Cerro Paranal in Chile. Full details of the VST and VISTA observations and overall scientific objectives of ShaSS are presented in Merluzzi et al (2015). In this article, we present the spectroscopic component of ShaSS: a redshift survey of the same region carried out using the AAOmega fibre-fed multiobject spectrograph at the 3.9 m Anglo Australian Telescope in 2013 May.…”

An Interacting Galaxy Pair at the Origin of a Light Echo

“…THE SHASS 073-622 SYSTEM 2.1. Target selection Our target has been identified as part of the Shapley Supercluster Survey (ShaSS, Merluzzi et al 2015). This survey covers 23 deg 2 centered on the Shapley Supercluster core (z ∼ 0.05) and combines observations in the ESO-VST ugri filters 1 with ESO-VISTA K-band imag-…”

OmegaWINGS: OmegaCAM-VST observations of WINGS galaxy clusters

“…Cosmological hydrodynamical simulations predict a depletion of both hot and cold gas and a decline in the star-forming fraction of galaxies as far out as five cluster virial radii (Bahé et al 2013). With the exception of a few single clusters and superclusters (e.g., Merluzzi et al 2010Merluzzi et al , 2015Mahajan et al 2011;Smith et al 2012;Haines et al 2011), this very important transition region between clusters and the surrounding field remains largely unexplored. With the aim to cover the virial region and extend out into the infall region, we have obtained GTO OmegaCAM/VST imaging in the u, B, and V bands over 1 × 1 deg 2 for 45 fields covering 46 WINGS clusters.…”