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arXiv · 0711.1863

Galaxy Cluster Correlation Function to z ~ 1.5 in the IRAC Shallow Cluster Survey

M. Brodwin·A. H. Gonzalez·L. A. Moustakas·P. R. Eisenhardt·S. A. Stanford·D. Stern·M. J. I. Brown
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Abstract

We present the galaxy cluster autocorrelation function of 277 galaxy cluster candidates with 0.25 \le z \le 1.5 in a 7 deg^2 area of the IRAC Shallow Cluster Survey. We find strong clustering throughout our galaxy cluster sample, as expected for these massive structures. Specifically, at = 0.5 we find a correlation length of r_0 = 17.40^{+3.98}_{-3.10} h^-1 Mpc, in excellent agreement with the Las Campanas Distant Cluster Survey, the only other non-local measurement. At higher redshift, = 1, we find that strong clustering persists, with a correlation length of r_0=19.14^{+5.65}_{-4.56} h^-1 Mpc. A comparison with high resolution cosmological simulations indicates these are clusters with halo masses of \sim 10^{14} Msun, a result supported by estimates of dynamical mass for a subset of the sample. In a stable clustering picture, these clusters will evolve into massive (10^{15} Msun) clusters by the present day.

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M. Brodwin, A. H. Gonzalez, L. A. Moustakas, P. R. Eisenhardt, S. A. Stanford, D. Stern, M. J. I. Brown. 2007-11-12. Galaxy Cluster Correlation Function to z ~ 1.5 in the IRAC Shallow Cluster Survey. https://doi.org/10.1086/525558

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