A Massive Cluster of Galaxies at Z = 0.996
نویسنده
چکیده
We report the identiication of a cluster of galaxies around the high-redshift radio galaxy 3CR184 at z = 0.996. The identiication is supported by an excess of galaxies observed in projection in I band images (both in ground-based and HST data), a peak in the redshift distribution comprising 11 galaxies (out of 56 with measured redshifts) in a 2000 km s ?1 velocity interval, and the observation on HST WFPC2 frames of a gravitational arc seen projected at 42h ?1 50 kpc away from the central radio galaxy. We thus have strong evidence for the presence of a massive cluster at z ' 1. The mass contained within the arc radius is in the range 1
منابع مشابه
6 v 1 1 0 A pr 1 99 7 A MASSIVE CLUSTER OF GALAXIES AT z = 0 . 996
We report the identification of a cluster of galaxies around the high-redshift radio galaxy 3CR184 at z = 0.996. The identification is supported by an excess of galaxies observed in projection in I band images (both in ground-based and HST data), a peak in the redshift distribution comprising 11 galaxies (out of 56 with measured redshifts) in a ∼ 2000 km s velocity interval, and the observation...
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