Simulations of the Square Kilometer Array

The images shown below were produced by generating simulated data (with realistic noise levels added) for various configurations of the proposed Square Kilometer Array. The data were generated in order to investigate how nest SKA can be used to provide mas resolution. Such high resolution will be necessary in order to resolve the microJy and sub-microJy radio source population accessible to SKA.

The model source (shown above) used to generate the data is similar to M82 or Arp 220 projected to cosmological distances. My conclusion is that SKA should be extended to trans-continental dimensions...

The image shown above is produced by the nominal SKA configuration described by Taylor and Braun (30, 200-m elements 80% of which are located within 50 km of each other, max baseline 1000km, total sensitivity 20000 meter squared/Kelvin). The data are dominated by the shortest SKA baselines and must be uniformly weighted in order to achieve reasonable angular resolution (10 mas in the image shown here). The rms noise is a factor of 2 higher than expected (50 nanoJy/beam) and the source is only barely resolved.

The image shown above is produced by a global VLBI network that includes the SKA as a highly sensitive phased array. The data (and the image) are completely dominated by the baselines involving the phased-array. The resolution is 1 mas and the noise is 170 nanoJy/beam. Most of the source goes undetected, except the AGN core (barely detected).

The image shown above was produced by an extended SKA i.e. 50% of the elements with 50 km of each other and the remaining 50% distributed across the globe. The resolution is 1.8 mas and the noise 21 nanoJy/beam. The array detects individual SNRs in the source and a low-luminosity AGN.

More details .. Read the Paper! .


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