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The Nearest Neighbor Alignment of Cluster X-ray Isophotes

Scott W. Chambers·Adrian L. Melott·Christopher J. Miller
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Abstract

We examine the orientations of rich galaxy cluster X-ray isophotes with respect to their rich nearest neighbors using existing samples of Abell cluster position angles measured from {\it Einstein} and {\it ROSAT} observations. We study a merged subset of these samples using updated and improved positions and redshifts for Abell/ACO clusters. We find high confidence for alignment, which increases as nearest neighbor distance is restricted. We conclude that there is a strong alignment signal in all this data, consistent with gravitational instability acting on Gaussian perturbations.

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Scott W. Chambers, Adrian L. Melott, Christopher J. Miller. 2001-09-10. The Nearest Neighbor Alignment of Cluster X-ray Isophotes. https://doi.org/10.1086/324278

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