Galaxies spatially coincident with the JKCS041 X-ray emission display a red sequence at z~2.2
Abstract
New deep z'-J data readly show a narrow red sequence co-centered with, and similary concentrated to, the extended X-ray emission of the cluster of galaxies JKCS041. The JKCS041 red sequence is 0.32+/-0.06 mag redder in z'-J than the red sequence of the zspec=1.62 IRC0218A cluster, putting JKCS041 at z<<1.62. The colour difference of the two red sequences gives a red-sequence based redshift of z=2.20+/-0.11 for JKCS041, where the uncertainty accounts for uncertainties in stellar synthesis population models, in photometric calibration and in the red sequence colour of both JKCS041 and IRC0218A clusters.
Cite
@article{arxiv.1012.3051,
title = {Galaxies spatially coincident with the JKCS041 X-ray emission display a red sequence at z~2.2},
author = {S. Andreon and M. Huertas-Company},
journal= {arXiv preprint arXiv:1012.3051},
year = {2010}
}
Comments
Mem SAIt, in press. Press-release and additional material related to this paper and to arXiv:1012.1951 (A&A 526, A11) can be found at http://www.brera.mi.astro.it/%7Eandreon/JKCS041/JKCS041.html