Alignments of the Galaxies in and around the Virgo Cluster with the Local Velocity Shear

Abstract

An observational evidence is presented for the alignment between the cosmic sheet and the principal axis of the velocity shear field at the position of the Virgo cluster. The galaxies in and around the Virgo cluster from the Extended Virgo Cluster Catalog recently constructed by Kim et al. are used to determine the direction of the local sheet. The peculiar velocity field reconstructed from the Sloan Digital Sky Survey Data Release 7 is analyzed to estimate the local velocity shear tensor at the Virgo center. Showing first that the minor principal axis of the local velocity shear tensor is almost parallel to the line of sight direction, we detect a clear signal of alignment between the positions of the Virgo satellites and the intermediate principal axis of the local velocity shear projected onto the plane of the sky. Furthermore, the dwarf satellites are found to appear more strongly aligned than the normal counterparts, which is interpreted as indication of the following: (i) The normal and the dwarf satellites fall in the Virgo cluster preferentially along the local filament and the local sheet, respectively. (ii) The local filament is aligned with the minor principal axis of the local velocity shear while the local sheet is in parallel to the plane spanned by the minor and the intermediate principal axes. Our result is consistent with the recent numerical claim that the velocity shear is a good tracer of the cosmic web.

Accepted for publication in ApJ, 5 figures

References in corpus (10)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Likelihoods and Parameters from the WMAP data
• Properties of Dark Matter Haloes in Clusters, Filaments, Sheets and Voids
• The Evolution of Dark Matter Halo Properties in Clusters, Filaments, Sheets and Voids
• Spin alignment of dark matter haloes in filaments and walls
• The spin and orientation of dark matter halos within cosmic filaments
• The three dimensional skeleton: tracing the filamentary structure of the universe
• Reconstructing the cosmic density field with the distribution of dark matter halos
• Quantifying Cosmic Superstructures
• Satellite Alignment: I. Distribution of Substructures and Their Dependence On Assembly History From N-Body Simulations
• Galaxy Orientations in the Coma Cluster

Cited by in corpus (8)

• The alignment of satellite galaxies and cosmic filaments: observations and simulations
• Intrinsic alignments of galaxies in the MassiveBlack-II simulation: analysis of two-point statistics
• Large-scale filamentary structures around the Virgo cluster revisited
• The Distribution of Satellites Around Central Galaxies in a Cosmological Hydrodynamical Simulation
• The Spectroscopy and H-band Imaging of Virgo cluster galaxies (SHIVir) Survey: Scaling Relations and the Stellar-to-Total Mass Relation
• A New Dynamical Mass Measurement for the Virgo Cluster using the Radial Velocity Profile of the Filament Galaxies
• Detection of the velocity shear effect on the spatial distributions of the galactic satellites in isolated systems
• An observational signal of the void shape correlation and its link to the cosmic web