The pre-launch Planck Sky Model: a model of sky emission at submillimetre to centimetre wavelengths

TL;DR

The paper introduces the Planck Sky Model, a comprehensive simulation tool for generating all-sky maps of sky emission at submillimetre to centimetre wavelengths, aiding in survey planning and data analysis validation.

Contribution

It presents a detailed, adaptable parametric model of sky emission components, incorporating spatially varying spectral properties and clustering, based on current observational data and models.

Findings

Enables realistic simulations matching observational data within uncertainties.

Supports optimization of microwave and sub-millimetre surveys.

Provides a software tool for experiment simulation and pipeline validation.

Abstract

We present the Planck Sky Model (PSM), a parametric model for the generation of 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; modeling 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 realizations of the sky emission, constrained to match observational data within their uncertainties, and 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 optimizing planned microwave and sub-millimetre surveys and to test data processing and analysis pipelines. It is, in particular, used for the development and validation of 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.