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All-sky thermal and kinetic Sunyaev–Zel'dovich (SZ) maps are presented for assessing how well the Planck mission can find and characterize clusters of galaxies, especially in the presence of primary anisotropies of the cosmic microwave background (CMB) and various Galactic and ecliptic foregrounds. The maps have been constructed from numerical simulations of structure formation in a standard Λ cold dark matter (ΛCDM) cosmology and contain all clusters out to redshifts of with masses exceeding . By construction, the maps properly account for the evolution of cosmic structure, the halo–halo correlation function, the evolving mass function, halo substructure and adiabatic gas physics. The velocities in the kinetic map correspond to the actual density environment at the cluster positions. We characterize the SZ-cluster sample by measuring the distribution of angular sizes, the integrated thermal and kinetic Comptonizations, the source counts in the three relevant Planck channels, and give the angular power spectra of the SZ sky. While our results are broadly consistent with simple estimates based on scaling relations and spherically symmetric cluster models, some significant differences are seen which may affect the number of cluster detectable by Planck. [ABSTRACT FROM AUTHOR]

We present the analysis of the first 18 months of data obtained with the COSMOSOMAS (COSMOlogical Structures On Medium Angular Scales) experiment at the Teide Observatory (Tenerife). Three maps have been obtained at 12.7, 14.7 and 16.3 GHz covering 9000 deg2 each with a resolution of ∼1° and with sensitivities 49, 59 and 115 μK beam−1, respectively. These data in conjunction with the Wilkinson Microwave Anisotropy Probe ( WMAP) first year maps have revealed that the cosmic microwave background (CMB) is the dominant astronomical signal at high galactic latitude in the three COSMOSOMAS channels with an average amplitude of (68 per cent c.l. not including calibration errors). This value is in agreement with the predicted CMB signal in the COSMOSOMAS maps using the best-fitting Λ-CDM model to the WMAP power spectrum. Cross-correlation analysis of the 408-MHz map and the COSMOSOMAS data at high galactic latitudes give values in the range from 12.7 to 16.3 GHz. Removing detected point sources in this template, reduces the amplitude of the correlated signal to 8–9 μK. The mean spectral index of the correlated signal between the 408 MHz desourced and the COSMOSOMAS maps is between −3.20 and −2.94 at which indicates that this signal is due to synchrotron emission. Cross-correlation of COSMOSOMAS data with the Diffuse Infrared Background Experiment (DIRBE) map at 100 μm shows the existence of a common signal with amplitude and in the 12.7, 14.7 and 16.3 GHz COSMOSOMAS maps at . Using the WMAP data, we find this DIRBE correlated signal rises from high to low frequencies flattening below ∼20 GHz. At higher galactic latitudes the average amplitude of the correlated signal with the DIRBE maps decreases slightly. The frequency behaviour of the COSMOSOMAS/ WMAP correlated signal with DIRBE is not compatible with the expected tendency for thermal dust. A study of the Hα emission maps do not support free–free as a major contributor to that signal. Our results provide new evidence of a Galactic foreground with properties compatible with predictions by spinning dust models. [ABSTRACT FROM AUTHOR]