Quasi-spherical superclusters

Abstract

Generally the dynamical state of superclusters is poorly known. We study properties of superclusters and select a sample of quasi-spherical superclusters, the dynamics of which can be studied using the $\Lambda$ significance diagram. We extracted our supercluster sample with an adaptive local threshold density method from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) data and estimated their masses using the dynamical masses for member galaxies and groups. We used topological analysis based on Minkowski functionals and the positions of galaxies and galaxy groups in superclusters. Finally, we highlight the dynamical state of a few exceptional types of superclusters found in this study using the $\Lambda$ significance diagram. Our final sample contains 65 superclusters in the distance range of 130 to 450 Mpc. Supercluster masses range between $1.1 \times 10^{15} M_{\sun}$ and $1.4 \times 10^{16} M_{\sun}$ and sizes between 25 Mpc and 87 Mpc. We find that pancake-type superclusters form the low-luminosity, small, poor and low-mass end of superclusters. We find four superclusters of unusual types, exhibiting exceptionally spherical shapes. These so-called quasi-spherical systems contain a high-density core surrounded by a relatively spherical density and galaxy distribution.The mass-to-light ratio of these quasi-sphericals is higher than those of the other superclusters, suggesting a relatively high dark matter content. Using the $\Lambda$ significance diagram for oblate and prolate spheroids, we find that three quasi-spherical superclusters are gravitationally bound at the present epoch. Quasi-spherical superclusters are among the largest gravitationally bound systems found to date, and form a special class of giant systems that, dynamically, are in between large gravitationally unbound superclusters and clusters of galaxies in an equilibrium configuration.

arXiv comment15 pages, 10 figures, 2 tables, accepted in Astronomy & Astrophysics

References in corpus (47)

• Planck 2013 results. XVI. Cosmological parameters
• Dark Energy and the Accelerating Universe
• The Galaxy Luminosity Function and Luminosity Density at Redshift z=0.1
• Where are the Baryons?
• Galaxy Cluster Virial Masses and Omega
• Where Are the Baryons? II: Feedback Effects
• The Laniakea supercluster of galaxies
• Flux- and volume-limited groups/clusters for the SDSS galaxies: catalogues and mass estimation
• Where is the Dark Matter?
• Optical and X-ray clusters as tracers of the supercluster-void network. I Superclusters of Abell and X-ray clusters
• Shapefinders: A new shape diagnostic for large scale structure
• Groups and clusters of galaxies in the SDSS DR8. Value-added catalogues
• SDSS DR7 superclusters. The catalogues
• Morphology of the supercluster-void network in LCDM cosmology
• Galaxy morphology, luminosity and, environment in the SDSS DR7
• The 2dF Galaxy Redshift Survey: Wiener Reconstruction of the Cosmic Web
• Galaxy Cluster Mass Reconstruction Project: II. Quantifying scatter and bias using contrasting mock catalogues
• Galaxy Cluster Mass Reconstruction Project: I. Methods and first results on galaxy-based techniques
• Large-scale mass distribution in the Illustris simulation
• A detection of the integrated Sachs-Wolfe imprint of cosmic superstructures using a matched-filter approach
• Clusters and Superclusters in the Sloan Digital Sky Survey
• How unusual are the Shapley Supercluster and the Sloan Great Wall?
• On the definition of superclusters
• Tracing mass and light in the Universe: where is the dark matter?
• The Limits of Bound Structures in the Accelerating Universe
• SDSS DR7 superclusters. Morphology
• PSCz Superclusters: Detection, Shapes & Cosmological Implications
• Dark energy and the structure of the Coma cluster of galaxies
• Future virialized structures: An analysis of superstructures in SDSS-DR7
• Mass and Light in the Supercluster of galaxies : MS0302+17
• Morphological Properties of Superclusters of Galaxies
• Detection of intercluster gas in superclusters using the thermal Sunyaev-Zel'dovich effect
• Sloan Great Wall as a complex of superclusters with collapsing cores
• Unusual A2142 supercluster with a collapsing core: distribution of light and mass
• Multiscale cosmic web detachments, connectivity, and preprocessing in the supercluster SClA2142 cocoon
• Non-Friedmann cosmology for the Local Universe, significance of the universal Hubble constant and short-distance indicators of dark energy
• Shape Statistics of Sloan Digital Survey superclusters
• Mass, Light and Colour of the Cosmic Web in the Supercluster SCL2243-0935 (z=0.447)
• Multi-scale morphology of the galaxy distribution
• SDSS DR7 superclusters. Principal component analysis
• The Corona Borealis supercluster: connectivity, collapse, and evolution
• Characteristic density contrasts in the evolution of superclusters. The case of A2142 supercluster
• Cosmic flow around local massive galaxies
• Partitioning the universe into gravitational basins using the cosmic velocity field
• The evolution of high-density cores of the BOSS Great Wall superclusters
• The Cosmic Large-Scale Structure in X-rays (CLASSIX) cluster survey IV: Superclusters in the local Universe at z <= 0.03
• A graph of dark energy significance on different spatial and mass scales

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