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The Discovery of Primeval Large-Scale Structures with Forming Clusters at Redshift 6

M. Ouchi·K. Shimasaku·M. Akiyama·K. Sekiguchi·H. Furusawa·S. Okamura·N. Kashikawa·M. Iye·T. Kodama·T. Saito·T. Sasaki·C. Simpson·T. Takata·T. Yamada·H. Yamanoi·M. Yoshida
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Abstract

We report the discovery of primeval large-scale structures (LSSs) including two proto-clusters in a forming phase at z=5.7. We carried out extensive deep narrow-band imaging in the 1 deg^2 sky of the Subaru/XMM-Newton Deep Field, and obtained a cosmic map of 515 Ly alpha emitters (LAEs) in a volume with a transverse dimension of 180 Mpc x 180 Mpc and a depth of ~40 Mpc in comoving units. This cosmic map shows filamentary LSSs, including clusters and surrounding 10-40 Mpc scale voids, similar to the present-day LSSs. Our spectroscopic follow-up observations identify overdense regions in which two dense clumps of LAEs with a sphere of 1-Mpc diameter in physical units are included. These clumps show about 130 times higher star-formation rate density, mainly due to a large overdensity, ~80, of LAEs. These clumps would be clusters in a formation phase involving a burst of galaxy formation.

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M. Ouchi, K. Shimasaku, M. Akiyama, K. Sekiguchi, H. Furusawa, S. Okamura, N. Kashikawa, M. Iye, T. Kodama, T. Saito, T. Sasaki, C. Simpson, T. Takata, T. Yamada, H. Yamanoi, M. Yoshida. 2004-12-29. The Discovery of Primeval Large-Scale Structures with Forming Clusters at Redshift 6. https://doi.org/10.1086/428499

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