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ATNF Daily Astronomy Picture

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27th of February 2015
 
ASKAP Highlights - Mk II Phased-Array Feed Performance
by Aaron Chippendale (CASS)
On-dish measurements from CSIRO's Mk II phased-array feed (PAF) have confirmed low-noise performance across the ASKAP frequency band. Sensitivity is significantly improved over the majority of the band and is doubled above 1.4 GHz compared to the Mk I PAF. A minimum system-temperature-on-efficiency (Tsys/η) of 78 K is reached at 1.23 GHz, and 95 K or better across the 0.835 to 1.8 GHz range. The gaps in the data at certain frequencies are due to radio transmissions from satellites that are stronger than Taurus A, the astronomical calibration source used for the above single dish measurement.

The improvement was achieved via more accurate experimental characterisation of the low-noise amplifier signal and noise parameters, and enhancement of the chequerboard array to better match these parameters.

ASKAP News: ASKAP PAF performance signficantly improved with Mk II system



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