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Clusters and Superclusters in the Sloan Survey

J. Einasto·E. Tago·M. Einasto·E. Saar
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Abstract

We find clusters and superclusters of galaxies using the Data Release 1 of the Sloan Digital Sky Survey. Density fields with smoothing lengthst of 10 and 0.8 Mpc/h are calculated. We found that galaxies and clusters in a high-density environment have luminosities that are five to ten times higher than in a low-density environment. Numerical simulations show that in underdense regions most particles form a rarefied population of pregalactic matter whereas in overdense regions most particles form a clustered population in rich clusters. Simulations show also that very massive superclusters are great attractors and have small bulk motions.

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J. Einasto, E. Tago, M. Einasto, E. Saar. 2004-08-25. Clusters and Superclusters in the Sloan Survey. https://arxiv.org/abs/astro-ph/0408463

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