We examine the ability of the future Planck mission to provide a catalogue of galaxy clusters observed via their Sunyaev-Zel ’ dovich distortion in the cosmic microwave background .
For this purpose we produce full-sky Sunyaev-Zel ’ dovich maps based on N-body simulations and scaling relations between cluster properties for several cosmological models .
We extrapolate the N-body simulations by a mass function to high redshifts in order to obtain a realistic SZ background .
The simulated Planck observations include , besides the thermal and kinematic Sunyaev-Zel ’ dovich effects , contributions from the primordial CMB , extragalactic point sources as well as Galactic dust , free-free and synchrotron emission .
A harmonic-space maximum-entropy method is used to separate the SZ signal from contaminating components in combination with a cluster detection algorithm based on thresholding and flux integration to identify clusters and to obtain their fluxes .
We estimate a survey sensitivity limit ( depending on the quality of the recovered cluster flux ) and provide cluster survey completeness and purity estimates .
We find that given our modelling and detection algorithm Planck will reliably detect at least several thousands of clusters over the full sky .
The exact number depends on the particular cosmological model ( up to 10000 cluster detections in a concordance \Lambda CDM model with \sigma _ { 8 } = 0.9 ) .
We show that the Galaxy does not significantly affect the cluster detection .
Furthermore , the dependence of the thermal SZ power spectrum on the matter variance on scales of 8 h ^ { -1 } Mpc and the quality of its reconstruction by the employed method are investigated .
Our simulations suggest that the Planck cluster sample will not only be useful as a basis for follow-up observations , but also will have the ability to provide constraints on cosmological parameters .