1996/11/26 by Michael E. Jones, Richard Saunders, Joanne C. Baker +11 · 2 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Astrophysics and Star Formation Studies #Cluster (spacecraft) #Cosmic microwave background #Galaxies: Formation, Evolution, Phenomena #Galaxy #Microwave #Optics #Physics #Quasar #ROSAT #Redshift #Sky #Telescope #astro-ph
paper · pdf · doi:10.1086/310564
8 pages, LaTeX, 2 PostScript figures. To appear in Astrophysical Journal Letters
arxiv created 1996/11/26 · openalex publication_date 1997/04/10 · arxiv updated 2015/06/24 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In a 15 GHz Ryle Telescope observation of PC 1643+4631A, B, a pair of quasars at redshifts z = 3.79 and 3.83 separated by 198'' on the sky, we find a decrement in the cosmic microwave background (CMB) of -380 ± 64 μJy in a 110'' × 175'' beam. Assuming this to be a Sunyaev-Zeldovich effect due to an intervening cluster, the minimum magnitude of the central temperature decrement is 560 μK. A serendipitous ROSAT observation shows that there is no X-ray-luminous cluster in the direction of the decrement at z < 1. The implied gas mass is ≳2 × 10 14 M ☉ (assuming a temperature of ~5 keV), indicating a total mass of more than 10 15 M ☉ . This result demonstrates the existence of a massive system too distant to be detected by its emission, but which can be found via its imprint on the CMB.