The Shape of Velocity Dispersion Profiles and the Dynamical State of Galaxy Clusters

Abstract

Motivated by the existence of the relationship between the dynamical state of clusters and the shape of the velocity dispersion profiles (VDP), we study the VDPs for Gaussian (G) and Non-Gaussian (NG) systems for a subsample of clusters from the Yang catalog. The groups cover a redshift interval of $0.03\le z\le 0.1$ with halo mass $\ge 10^{14}$M${}_{\odot }$. We use a robust statistical method, Hellinger Distance, to classify the dynamical state of the systems according to their velocity distribution. The stacked VDP of each class, G and NG, is then determined using either Bright or Faint galaxies. The stacked VDP for G groups displays a central peak followed by a monotonically decreasing trend which indicates a predominance of radial orbits, with the Bright stacked VDP showing lower velocity dispersions in all radii. The distinct features we find in NG systems are manifested not only by the characteristic shape of VDP, with a depression in the central region, but also by a possible higher infall rate associated with galaxies in the Faint stacked VDP.

5 pages, 4 figures, accepted for publication in the MNRAS Letters

References in corpus (6)

• Galaxy Groups in the SDSS DR4: I. The Catalogue and Basic Properties
• LoCuSS: The slow quenching of star formation in cluster galaxies and the need for pre-processing
• On the efficiency and reliability of cluster mass estimates based on member galaxies
• Brightest Cluster Galaxies at the Present Epoch
• NoSOCS in SDSS. I. Sample Definition and Comparison of Mass Estimates
• Investigating the Relation between Galaxy Properties and the Gaussianity of the Velocity Distribution of Groups and Clusters

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