Discovery of an Arc System in the Brightest ROSAT Cluster of Galaxies

S. Schindler; L. Guzzo; H. Ebeling; H. Böhringer; G. Chincarini; C. A. Collins; S. De Grandi; D. M. Neumann; U. G. Briel; P. Shaver; G. Vettolani

arXiv · astro-ph/9505097

Discovery of an Arc System in the Brightest ROSAT Cluster of Galaxies

S. Schindler·L. Guzzo·H. Ebeling·H. Böhringer·G. Chincarini·C. A. Collins·S. De Grandi·D. M. Neumann·U. G. Briel·P. Shaver·G. Vettolani

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Abstract

We report the discovery of two bright arcs in what turns out to be the brightest X--ray cluster in the ROSAT band ever observed, RXJ1347.5-1145. Its luminosity is $(6.2\pm0.6) \cdot10^{45}$erg s$^{-1}$ (in the range 0.1--2.4~keV). The arcs are most probably gravitationally lensed images of background galaxies. They were found serendipitously during our ongoing large--scale redshift survey of X--ray clusters detected by the ROSAT All Sky Survey. The arcs are almost opposite to each other with respect to the cluster centre, with a distance from it of about $35''$ ($=240 h^{-1}_{50}$ kpc), a radius that enables the probing of a rather large cluster volume. In this Letter we limit ourselves to the discussion of the general optical and X--ray features of this cluster and to the potential implications of the gravitational arcs. A more detailed discussion of the different mass estimates and of the cosmological implications for this exceptional object are left for future work based on more accurate optical and X--ray data, which are currently being collected.

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S. Schindler, L. Guzzo, H. Ebeling, H. Böhringer, G. Chincarini, C. A. Collins, S. De Grandi, D. M. Neumann, U. G. Briel, P. Shaver, G. Vettolani. 1995-05-22. Discovery of an Arc System in the Brightest ROSAT Cluster of Galaxies. https://arxiv.org/abs/astro-ph/9505097

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