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We present first results from pilot observations using a phased array feed (PAF) mounted on the Parkes 64-m radio telescope. The observations presented here cover a frequency range from 1150 to 1480 MHz and are used to show the ability of PAFs to suppress standing wave problems by a factor of $sim10$ which afflict normal feeds. We also compare our results with previous HIPASS observations and with previous HI images of the Large Magellanic Cloud. Drift scan observations of the GAMA G23 field resulted in direct HI detections at $z=0.0043$ and $z=0.0055$ of HIPASS galaxies J2242-30 and J2309-30. Our new measurements generally agree with archival data in spectral shape and flux density, with small differences being due to differing beam patterns. We also detect signal in the stacked HI data of 1094 individually undetected galaxies in the GAMA G23 field in the redshift range $0.05 leq z leq 0.075$. Finally, we use the low standing wave ripple and wide bandwidth of the PAF to set a $3sigma$ upper limit to any positronium recombination line emission from the Galactic Centre of $<0.09$ K, corresponding to a recombination rate of $<3.0times10^{45},mathrm{s}^{-1}$.
During February 2016, CSIRO Astronomy and Space Science and the Max-Planck-Institute for Radio Astronomy installed, commissioned and carried out science observations with a phased array feed (PAF) receiver system on the 64m diameter Parkes radio tele
In this report we present a model for phased array feed (PAF) and compare the model predictions with measurements. A theory for loss-less PAF is presented first. To develop the theory we ask the question -- what is the best $T_{sys}/eta_{ap}$ that ca
A new 1.4 GHz 19-element, dual-polarization, cryogenic phased array feed (PAF) radio astronomy receiver has been developed for the Robert C. Byrd Green Bank Telescope (GBT) as part of FLAG (Focal L-band Array for the GBT) project. Commissioning obser
We have measured the aperture-array noise temperature of the first Mk. II phased array feed that CSIRO has built for the Australian Square Kilometre Array Pathfinder telescope. As an aperture array, the Mk. II phased array feed achieves a beam equiva
This paper presents the measured sensitivity of CSIROs first Mk. II phased array feed (PAF) on an ASKAP antenna. The Mk. II achieves a minimum system-temperature-over-efficiency $T_mathrm{sys}/eta$ of 78 K at 1.23 GHz and is 95 K or better from 835 M