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arXiv · 1106.3766

Sunyaev Zel'dovich observations of a statistically complete sample of galaxy clusters with OCRA-p

Katy Lancaster·Mark Birkinshaw·Marcin P. Gawronski·Richard Battye·Ian Browne·Richard Davis·Paul Giles·Roman Feiler·Andrzej Kus·Bartosz Lew·Stuart Lowe·Ben Maughan·Abdulaziz Mohammad·Bogna Pazderska·Eugeniusz Pazderski·Mike Peel·Boud Roukema·Peter Wilkinson
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Abstract

We present 30 GHz Sunyaev Zel'dovich observations of a statistically complete sample of galaxy clusters with OCRA-p. The clusters are the 18 most X-ray luminous clusters at z > 0.2 in the ROSAT Brightest Cluster Sample. We correct for contaminant radio sources via supplementary observations with the Green Bank Telescope, also at 30 GHz, and remove a cluster that is contaminated by an unresolved X-ray source. All 17 remaining clusters have central SZ effects with Comptonisation parameter y_0 exceeding 1.9x10^-4, and 13 are detected at significance > 3 sigma. We use our data to examine scalings between y_0 and X-ray temperature, X-ray luminosity, and the X-ray mass proxy Y_X, and find good agreement with predictions from self-similar models of cluster formation, with an intrinsic scatter in y_0 of about 25%. We also comment on the success of the observations in the face of the contaminant source population, and the implications for upcoming cm-wave surveys.

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Katy Lancaster, Mark Birkinshaw, Marcin P. Gawronski, Richard Battye, Ian Browne, Richard Davis, Paul Giles, Roman Feiler, Andrzej Kus, Bartosz Lew, Stuart Lowe, Ben Maughan, Abdulaziz Mohammad, Bogna Pazderska, Eugeniusz Pazderski, Mike Peel, Boud Roukema, Peter Wilkinson. 2011-06-19. Sunyaev Zel'dovich observations of a statistically complete sample of galaxy clusters with OCRA-p. https://doi.org/10.1111/j.1365-2966.2011.19241.x

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