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arXiv · astro-ph/0412460

Discovery of a Large Scale Clumpy Structure around the Lynx Supercluster at z~1.27

Fumiaki Nakata·Tadayuki Kodama·Kazuhiro Shimasaku·Mamoru Doi·Hisanori Furusawa·Masaru Hamabe·Masahiko Kimura·Yutaka Komiyama·Satoshi Miyazaki·Sadanori Okamura·Masami Ouchi·Maki Sekiguchi·Yoshihiro Ueda·Masafumi Yagi·Naoki Yasuda
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Abstract

We report the discovery of a probable large scale structure composed of many galaxy clumps around the known twin clusters at z=1.26 and z=1.27 in the Lynx region. Our analysis is based on deep, panoramic, and multi-colour imaging (26.4'x24.1') in VRi'z'-bands with the Suprime-Cam on the 8.2m Subaru telescope. This unique, deep and wide-field imaging data-set allows us for the first time to map out the galaxy distribution in the highest redshift supercluster known. We apply a photometric redshift technique to extract plausible cluster members at z~1.27 down to i'=26.15 (5sigma) corresponding to M*+2.5 at this redshift. From the 2-D distribution of these photometrically selected galaxies, we newly identify seven candidates of galaxy groups or clusters where the surface density of red galaxies is significantly high (>5sigma), in addition to the two known clusters. These candidates show clear red colour-magnitude sequences consistent with a passive evolution model, which suggests the existence of additional high density regions around the Lynx superclusters.

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Fumiaki Nakata, Tadayuki Kodama, Kazuhiro Shimasaku, Mamoru Doi, Hisanori Furusawa, Masaru Hamabe, Masahiko Kimura, Yutaka Komiyama, Satoshi Miyazaki, Sadanori Okamura, Masami Ouchi, Maki Sekiguchi, Yoshihiro Ueda, Masafumi Yagi, Naoki Yasuda. 2004-12-17. Discovery of a Large Scale Clumpy Structure around the Lynx Supercluster at z~1.27. https://doi.org/10.1111/j.1365-2966.2005.08756.x

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