The pre-launchPlanckSky Model: a model of sky emission at submillimetre to centimetre wavelengths

Abstract

We present the Planck Sky Model (PSM), a parametric model for generating all-sky, few arcminute resolution maps of sky emission at submillimetre to centimetre wavelengths, in both intensity and polarisation. Several options are implemented to model the cosmic microwave background, Galactic diffuse emission (synchrotron, free-free, thermal and spinning dust, CO lines), Galactic H ii regions, extragalactic radio sources, dusty galaxies, and thermal and kinetic Sunyaev-Zeldovich signals from clusters of galaxies. Each component is simulated by means of educated interpolations/extrapolations of data sets available at the time of the launch of the Planck mission, complemented by state-of-the-art models of the emission. Distinctive features of the simulations are spatially varying spectral properties of synchrotron and dust; different spectral parameters for each point source; modelling of the clustering properties of extragalactic sources and of the power spectrum of fluctuations in the cosmic infrared background. The PSM enables the production of random realisations of the sky emission, constrained to match observational data within their uncertainties. It is implemented in a software package that is regularly updated with incoming information from observations. The model is expected to serve as a useful tool for optimising planned microwave and sub-millimetre surveys and testing data processing and analysis pipelines. It is, in particular, used to develop and validate data analysis pipelines within the Planck collaboration. A version of the software that can be used for simulating the observations for a variety of experiments is made available on a dedicated website.

Planck2015 results

“…For the fiducial realization, maps were made of the total observation (CMB, foregrounds, and noise) at each frequency for the nominal mission period, using the Planck Sky Model (Delabrouille et al 2013). In addition, maps were made of each component separately, of subsets of detectors at each frequency, and of halfring and single Survey subsets of the data.…”

Planck2013 results. XV. CMB power spectra and likelihood

“…Here we compare the posterior distributions of cosmological and foreground parameters, together with calibration and beam error parameters, inferred using the Plik likelihood, with the input values of a set of simulations, referred to as "Full Focal Plane" (FFP6). The signals in these simulations are based on the "Planck Sky Model" (Delabrouille et al 2013), which includes a detailed model of the astrophysical emission, both Galactic and extragalactic, at the Planck frequencies. The simulations also reproduce in detail the main instrumental systematic effects of Planck, including correlated time-line noise, instrumental pointing, flags, anisotropic detector beams, and spectral bandpasses.…”

Planck2013 results. XXVIII. ThePlanckCatalogue of Compact Sources

“…VII 2013; Delabrouille et al 2013). We require that the simulated catalogues pass two internal consistency tests: that they have the same injected source completeness as the real catalogues calculated as outlined above; and that they have total detected number counts, as a function of S/N, that are consistent with those in the real data.…”