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1E0657-56: A Contender for the Hottest Known Cluster of Galaxies

W. Tucker·P. Blanco·S. Rappoport·L. David·D. Fabricant·E. E. Falco·W. Forman·A. Dressler·M. Ramella
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Abstract

We identify the extended Einstein IPC X-ray source, 1E0657-56, with a previously unknown cluster of galaxies at a redshift of $z=0.296$. Optical CCD images show the presence of a gravitational arc in this cluster and galaxy spectra yield a cluster velocity dispersion of $1213^{+352}_{-191}$ km s$^{-1}$. X-ray data obtained with the ROSAT HRI and ASCA indicate that 1E0657-56 is a highly luminous cluster in which a merger of subclusters may be occurring. The temperature of the hot gas in 1E0657-56 is $\rm{kT}=17.4 \pm 2.5 keV$, which makes it an unusually hot cluster, with important cosmological implications.

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W. Tucker, P. Blanco, S. Rappoport, L. David, D. Fabricant, E. E. Falco, W. Forman, A. Dressler, M. Ramella. 1998-01-13. 1E0657-56: A Contender for the Hottest Known Cluster of Galaxies. https://doi.org/10.1086/311234

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