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The Planck-ATCA Co-eval Observations (PACO) project has yielded observations of 464 sources with the Australia Telescope Compact Array (ATCA) between 4.5 and 40 GHz. The main purpose of the project was to investigate the spectral properties of mm-selected radio sources at frequencies below and overlapping with the ESAs Planck satellite frequency bands, minimizing the variability effects by observing almost simultaneously with the first two Planck all-sky surveys. In this paper we present the whole catalogue of observations in total intensity. By comparing PACO with the various measures of Planck Catalog of Compact Sources (PCCS) flux densities we found the best consistency with the PCCS detection pipeline photometry (DETFLUX) that we used to investigate the spectral properties of sources from 5 to 217 GHz. Of our sources, 91% have remarkably smooth spectrum, well described by a double power law over the full range. This suggests a single emitting region, at variance with the notion that flat spectra result from the superposition of the emissions from different compact regions, self absorbed up to different frequencies. Most of the objects show a spectral steepening above 30 GHz, consistent with synchrotron emission becoming optically thin. Thus, the classical dichotomy between flat-spectrum/compact and steep-spectrum/extended radio sources, well established at cm wavelengths, breaks down at mm wavelengths. The mm-wave spectra do not show indications of the spectral break expected as the effect of electron ageing, suggesting young source ages.
A fraction of galaxy clusters host diffuse radio sources whose origins are investigated through multi-wavelength studies of cluster samples. We investigate the presence of diffuse radio emission in a sample of seven galaxy clusters in the largely une
A complete, flux density limited sample of 96 faint ($> 0.5$ mJy) radio sources is selected from the 10C survey at 15.7 GHz in the Lockman Hole. We have matched this sample to a range of multi-wavelength catalogues, including SERVS, SWIRE, UKIDSS and
We investigate the possible presence of diffuse radio emission in the intermediate redshift, massive cluster PLCK G285.0-23.7 (z=0.39, M_500 = 8.39 x 10^(14) M_Sun). Our 16cm-band ATCA observations of PLCK G285.0-23.7 allow us to reach a rms noise le
The Lockman Hole is a well-studied extragalactic field with extensive multi-band ancillary data covering a wide range in frequency, essential for characterising the physical and evolutionary properties of the various source populations detected in de
Dwarf spheroidal (dSph) galaxies are key objects in near-field cosmology, especially in connection to the study of galaxy formation and evolution at small scales. In addition, dSphs are optimal targets to investigate the nature of dark matter. Howeve