2011/06/30 by Planck Collaboration, N. Aghanim, M. Arnaud +202 · 1 citation
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #Galaxy #Physics #Planck #astro-ph.CO
paper · pdf · doi:10.1051/0004-6361/201117430
6 pages, 3 figures; final version accepted for publication in A&A ; minor changes in Sec.2.,3.2 and 4.1; Table 1: misprint on R500 error corrected; abundance value added
arxiv created 2011/07/27 · openalex publication_date 2011/08/01 · arxiv updated 2015/05/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present first results on PLCKG266.6−27.3, a galaxy cluster candidate detected at a signal-to-noise ratio of 5 in the Planck All Sky survey. An XMM-Newton validation observation has allowed us to confirm that the candidate isa bona fide galaxy cluster. With these X-ray data we measure an accurate redshift, z = 0.94 ± 0.02, and estimate the cluster mass to be M500 = (7.8 ± 0.8) × 1014 M⊙. PLCKG266.6−27.3 is an exceptional system: its luminosity of LX [0.5−2.0 keV] = (1.4 ± 0.05) × 1045 erg s-1 equals that of the two most luminous known clusters in the z > 0.5 universe, and it is one of the most massive clusters at z ~ 1. Moreover, unlike the majority of high-redshift clusters, PLCKG266.6−27.3 appears to be highly relaxed. This observation confirms Planck’s capability of detecting high-redshift, high-mass clusters, and opens the way to the systematic study of population evolution in the exponential tail of the mass function.