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arXiv · 1008.3426

The architecture of Abell 1386 and its relationship to the Sloan Great Wall

Kevin A. Pimbblet·Heinz Andernach·Cherie K. Fishlock·Isaac G. Roseboom·Matthew S. Owers
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Abstract

We present new radial velocities from AAOmega on the Anglo-Australian Telescope for 307 galaxies (b_J < 19.5) in the region of the rich cluster Abell 1386. Consistent with other studies of galaxy clusters that constitute sub-units of superstructures, we find that the velocity distribution of A1386 is very broad (21,000--42,000 kms^-1, or z=0.08--0.14) and complex. The mean redshift of the cluster that Abell designated as number 1386 is found to be ~0.104. However, we find that it consists of various superpositions of line-of-sight components. We investigate the reality of each component by testing for substructure and searching for giant elliptical galaxies in each and show that A1386 is made up of at least four significant clusters or groups along the line of sight whose global parameters we detail. Peculiar velocities of brightest galaxies for each of the groups are computed and found to be different from previous works, largely due to the complexity of the sky area and the depth of analysis performed in the present work. We also analyse A1386 in the context of its parent superclusters: Leo A, and especially the Sloan Great Wall. Although the new clusters may be moving toward mass concentrations in the Sloan Great Wall or beyond, many are most likely not yet physically bound to it.

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Kevin A. Pimbblet, Heinz Andernach, Cherie K. Fishlock, Isaac G. Roseboom, Matthew S. Owers. 2010-08-20. The architecture of Abell 1386 and its relationship to the Sloan Great Wall. https://doi.org/10.1111/j.1365-2966.2010.17565.x

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