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abstract: |
    We present 30GHz 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 30GHz, 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 $1.9\times10^{-4}$, and 13 are detected at significance $\ge 3
    \sigma$. We use our data to examine scalings between $y_0$ and X-ray temperature, X-ray luminosity, and the X-ray mass proxy $Y_\mathrm{X}$, 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.
author:
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    Katy Lancaster$^1$, Mark Birkinshaw$^1$, Marcin P. Gawroński$^2$, Richard Battye$^3$, Ian Browne$^3$, Richard Davis$^3$, Paul Giles$^1$, Roman Feiler$^2$, Andrzej Kus$^2$, Bartosz Lew$^2$, Stuart Lowe$^3$, Ben Maughan$^1$, Abdulaziz Mohammad$^1$, Bogna Pazderska$^2$, Eugeniusz Pazderski$^2$, Mike Peel$^3$, Boud Roukema$^2$ and Peter Wilkinson$^3$\
    $^1$ H. H. Wills 