A Large Population of High Redshift Galaxy Clusters in the IRAC Shallow Cluster Survey

Mark Brodwin; Peter R. Eisenhardt; Anthony H. Gonzalez; Adam Stanford; Daniel Stern; Leonidas A. Moustakas; Michael J. I. Brown; Ranga-Ram Chary; Audrey Galametz

arXiv · 0805.0813

A Large Population of High Redshift Galaxy Clusters in the IRAC Shallow Cluster Survey

Mark Brodwin·Peter R. Eisenhardt·Anthony H. Gonzalez·Adam Stanford·Daniel Stern·Leonidas A. Moustakas·Michael J. I. Brown·Ranga-Ram Chary·Audrey Galametz

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Abstract

We have identified 335 galaxy cluster and group candidates spanning 0 1, and over 60 at z < 0.5 have been spectroscopically confirmed. The mean I-[3.6] color for cluster galaxies up to z~1 is well matched by a z_f=3 passively evolving model. At z>1, a wider range of formation histories is needed, but higher formation redshifts (i.e. z_f \ge 4-5) are favored for most clusters. The cluster autocorrelation function, measured for the first time out to z=1.5, is found not to have evolved over the last 10 Gyr, in agreement with the prediction from LCDM. The average mass of the IRAC Shallow Cluster Survey sample, inferred from its clustering, is ~ 10^14 Msun.

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Mark Brodwin, Peter R. Eisenhardt, Anthony H. Gonzalez, Adam Stanford, Daniel Stern, Leonidas A. Moustakas, Michael J. I. Brown, Ranga-Ram Chary, Audrey Galametz. 2008-05-06. A Large Population of High Redshift Galaxy Clusters in the IRAC Shallow Cluster Survey. https://arxiv.org/abs/0805.0813

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