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1WGAJ1226.9+3332: a high redshift cluster discovered by Chandra

I. Cagnoni·M. Elvis·D. -W. Kim·P. Mazzotta·J. -S. Huang·A. Celotti
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Abstract

We report the detection of 1WGAJ1226.9+3332 as an arcminute scale extended X-ray source with the Chandra X-ray Observatory. The Chandra observation and R and K band imaging strongly support the identification of 1WGAJ1226.9+3332 as a high redshift cluster of galaxies, most probably at z=0.85 +- 0.15, with an inferred temperature kT =10 (+4;-3) keV and an unabsorbed luminosity (in a r=120" aperture) of 1.3 (+0.16;-0.14) x 1e45 erg/s (0.5-10 keV). This indication of redshift is also supported by the K and R band imaging, and is in agreement with the spectroscopic redshift of 0.89 found by Ebeling et al. (2001). The surface brightness profile is consistent with a beta-model with beta=0.770 +- 0.025, rc=(18.1 +-0.9)" (corresponding to 101 +- 5 kpc at z=0.89), and S(0)=1.02 +- 0.08 counts/arcsec**2. 1WGAJ1226.9+3332 was selected as an extreme X-ray loud source with FX/FV>60; this selection method, thanks to the large area sampled, seems to be a highly efficient method for finding luminous high z clusters of galaxies.

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I. Cagnoni, M. Elvis, D. -W. Kim, P. Mazzotta, J. -S. Huang, A. Celotti. 2001-06-05. 1WGAJ1226.9+3332: a high redshift cluster discovered by Chandra. https://doi.org/10.1086/322423

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