S3The SKA Simulated Skies
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The SKA Simulated Skies (S3) are a set of computer simulations of the radio and (sub)millimeter universe, primarily dedicated to the preparation of the Square Kilometer Array (SKA) and its pathfinders. These simulations were led by the University of Oxford as part of the Square Kilometer Array Design Studies (SKADS, European Community Framework Programme 6, contract #011938).

Simulation types


There are two simulations of radio emission from the Milky Way galaxy:
S3-GAL is a model of the galactic radio and (sub)millimeter foreground from 10 MHz to 100 GHz, which includes smooth emission as well as point sources, such as prominent supernova remnants. (Ref.: De Oliveira-Costa et al., 2008)
S3-PUL is a simulation of a Galactic population of pulsars. The database lists the position of the pulsars and includes an average pulse profile for each source. (Ref.: Karastergiou & Johnston, 2007)

There are two simulations of extragalactic radio and (sub)millimeter emission from galaxies beyond the Milky Way:
S3-SEX is a simulation of extragalactic radio continuum sources in a sky area of 20×20 deg2, out to a cosmological redshift of z = 20. In this simulation, the sources were drawn from observed (or extrapolated) luminosity functions and grafted onto an underlying dark matter density field with biases which reflect their measured large-scale clustering. (Ref.: Wilman et al., 2008)
S3-SAX is a semi-analytic simulation of neutral atomic (HI) and molecular (H2) hydrogen in galaxies and associated radio and (sub)millimeter emission lines, i.e. the HI-line and various CO-lines. (Refs.: Obreschkow et al., 2009b; Obreschkow et al., 2009c; Obreschkow et al., 2009d)

The final simulation, S3-EOR, is a simulation the HI-line (1.420 GHz rest-frame) in of the Intergalactic Medium (IGM) during the Epoch of Reionization (EoR). This simulation includes both emission and absorption signals. (Ref.: Santos et al., 2008)

Post-processing tools

A number of tools (S3-Tools) have been developed to post-process the simulated sky data. These are standalone python routines, which can be used to build fits-files (maps and cubes) from the simulated sky data of S3-SEX, S3-SAX, S3-GAL, and S3-EOR.

Credits to institutions and funding agencies

This project has been supported by the University of Oxford (sub-department of Astrophysics and Oxford e-Research Centre) and by the European Community Framework Programme 6, Square Kilometer Array Design Study (SKADS), contract #011938.

The Millennium Simulation databases, which are the basis of the S3-SAX simulation, and the web application providing online access to them were constructed as part of the activities of the German Astrophysical Virtual Observatory. The polarization efforts have been supported by the Cavendish Laboratory at the University of Cambridge and the Max Planck Institut für Radioastronomie in Bonn. The EoR simulation efforts have been supported by the Observatoire de Paris and the Instituto Superior Técnico (Lisbon).

Credits to scientists

University of Oxford: S. Rawlings, H.-R. Klöckner, F. Levrier, D. Obreschkow, A. Karastergiou, R. Wilman, A. Smith, S. Young
University of Cambridge: P. Alexander, M. Krause, J. Geisbüsch
University of Hertfordshire: M. Jarvis
Observatoire de Paris: F. Combes, B. Semelin, S. Baek, P. di Matteo, Y. Revaz
Instituto Superior Técnico: M. G. Santos, L. D. Ferramacho, M. B. Silva
Max-Planck-Institut für Radioastronomie: R. Beck, T. Arshakian
Massachusetts Institute of Technology: A. de Oliveira-Costa