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arXiv · astro-ph/9909166

Lensed Arcs and Inner Structure of Abell 697

Mark R. Metzger·Chung-Pei Ma
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Abstract

We present new optical observations of the z=0.282 cluster Abell 697 from the Keck II telescope. Images show an unusual disturbed structure in the cD halo and a previously unknown faint gravitational lens arc. A spectrum of the arc did not yield a redshift, but its spectrum and colors suggest it lies at z>1.3. We construct models to reproduce the arc that show the potential is likely to be highly elliptical. We suggest that this cluster may have undergone a recent merger and is in the process of forming its cD galaxy. Analysis of X-ray data from ROSAT and ASCA suggests that the merging process is sufficiently advanced that the gas in the cluster has relaxed, and A697 lies near the L_x-T_x relation for normal clusters.

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Mark R. Metzger, Chung-Pei Ma. 1999-09-09. Lensed Arcs and Inner Structure of Abell 697. https://doi.org/10.1086/316843

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