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arXiv · 1505.07864

Three candidate clusters around high redshift radio-loud sources: MG1 J04426+0202, 3C 068.2, MS 1426.9+1052

J. R. Franck·S. S. McGaugh·J. M. Schombert
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Abstract

We present near-infrared observations of the environments around three radio-loud sources (MG1 J0442+0202, 3C 068.2, and MS 1426.9+1052) at redshifts z=1.10,1.57, and 1.83 (respectively), that are surrounded by near-infrared galaxy overdensities. Overdensities with respect to field counts were found to be significant up to 19-sigma, with twelve times the expected number of galaxies within the inner regions of the densest proto-cluster. Color-magnitude relations are constructed in K_s, J-K_s, with each candidate cluster exhibiting a feature consistent with the beginnings of a red sequence. Galaxy models based on the redshift of the radio source are used to compare expected color-magnitude relations for a given formation epoch with the observed red sequence of each candidate, and are found to be consistent with an old (z_f > 5) formation epoch for a few bright, red galaxies on the red sequence.

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J. R. Franck, S. S. McGaugh, J. M. Schombert. 2015-05-28. Three candidate clusters around high redshift radio-loud sources: MG1 J04426+0202, 3C 068.2, MS 1426.9+1052. https://doi.org/10.1088/0004-6256%2F150%2F2%2F46

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