on the results of this study, with additional information on X-ray variability, IR excess, and optical spectral types, individual membership classifications for the CCCP sources are derived by @Broos11b.

Simulations of Cluster Contaminants \[contaminants\_main\_section\]
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Extragalactic Sources \[contaminants\_agn\_section\]
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We evaluate the expected contamination by extragalactic X-ray sources using methods similar to the analyses of @Getman05 [@Getman06]. Nominal (corresponding to the the high Galactic latitude fields with low Galactic absorbing column used for extragalactic studies) hard-band ($2-8$ keV) fluxes incident on [*Chandra*]{} are drawn from the $\log N - \log S$ distribution of extragalactic sources described by @Moretti03 assuming a power law source spectrum consistent with flux-dependencies described by @Brandt01. More than 22600 extragalactic sources down to a nominal flux of $\log(F_X) = -16.7$ erg cm$^{-2}$ s$^{-1}$ are predicted for the 1.42 deg$^{2}$ CCCP field. One hundred Monte Carlo simulations are constructed by placing $>22600$ artificial sources randomly across the CCCP field. Source photon indices are drawn from uniform distributions in the ranges $-0.5 < \Gamma < 2$ and $1 < \Gamma < 2$ for nominal fluxes $\log(F_X) < -14.1$ erg cm$^{-2}$ s$^{-1}$ and $\log(F_X) > -14.1$ erg cm$^{-2}$ s$^{-1}$, respectively.

The nominal flux of each simulated source is transformed 