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arXiv · astro-ph/0110072

History of mass assembly and star formation in clusters

T. Kodama·Ian Smail·F. Nakata·S. Okamura·R. G. Bower
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Abstract

We present deep, panoramic multi-color imaging of the distant rich cluster A851 (z=0.41) using Suprime-Cam on Subaru. These images cover a 27' field of view (~11 h_{50}^{-1}Mpc), and by exploiting photometric redshifts, we can isolate galaxies in a narrow redshift slice at the cluster redshift. Using a sample of ~2700 probable cluster members ( M*+1) at a local density of 100 gal. Mpc^{-2}. The transition in the color-local density behavior occurs at densities corresponding to subclumps within the filaments surrounding the cluster. Identifying the sites where the transition occurs brings us much closer to understanding the mechanisms which are responsible for establishing the present-day relationship between environment and galaxy characteristics.

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T. Kodama, Ian Smail, F. Nakata, S. Okamura, R. G. Bower. 2001-10-03. History of mass assembly and star formation in clusters. https://arxiv.org/abs/astro-ph/0110072

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