Search Publications
The Evolutionary Map of the Universe pilot survey
Reiprich, Thomas H.; Koribalski, Bärbel S.; Norris, Ray P. +45 more
We present the data and initial results from the first pilot survey of the Evolutionary Map of the Universe (EMU), observed at 944 MHz with the Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The survey covers $270 deg^2$ of an area covered by the Dark Energy Survey, reaching a depth of 25-30 $µJy beam^{-1}$ rms at a spatial …
Unexpected circular radio objects at high Galactic latitude
Koribalski, Bärbel S.; Norris, Ray P.; Hopkins, Andrew M. +28 more
We have found a class of circular radio objects in the Evolutionary Map of the Universe Pilot Survey, using the Australian Square Kilometre Array Pathfinder telescope. The objects appear in radio images as circular edge-brightened discs, about one arcmin diameter, that are unlike other objects previously reported in the literature. We explore seve…
The ASKAP Variables and Slow Transients (VAST) Pilot Survey
Ramsay, Gavin; Kaplan, David L.; Gaensler, B. M. +52 more
The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $∼ 5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot s…
The MAGPI survey: Science goals, design, observing strategy, early results and theoretical framework
Fisher, D. B.; Peng, Y.; Gupta, A. +40 more
We present an overview of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey, a Large Program on the European Southern Observatory Very Large Telescope. MAGPI is designed to study the physical drivers of galaxy transformation at a lookback time of 3-4 Gyr, during which the dynamical, morphological, and chemical prope…
The radioactive nuclei (\textbf{26}) Al and (\textbf{60}) Fe in the Cosmos and in the solar system
Wang, W.; Diehl, R.; den Hartogh, J. W. +15 more
The cosmic evolution of the chemical elements from the Big Bang to the present time is driven by nuclear fusion reactions inside stars and stellar explosions. A cycle of matter recurrently re-processes metal-enriched stellar ejecta into the next generation of stars. The study of cosmic nucleosynthesis and this matter cycle requires the understandi…
Diffuse galaxy cluster emission at 168 MHz within the Murchison Widefield Array Epoch of Reionization 0-h field
Pratt, G. W.; Johnston-Hollitt, M.; Offringa, A. R. +3 more
We detect and characterise extended, diffuse radio emission from galaxy clusters at 168 MHz within the Epoch of Reionization 0-h field: a$45^{\circ} \times 45^{\circ}$region of the southern sky centred on R. A.${}= 0^{\circ}$, decl.${}=-27^{\circ}$. We detect 29 sources of interest; a newly detected halo in Abell 0141; a newly detected relic in Ab…
Low-frequency integrated radio spectra of diffuse, steep-spectrum sources in galaxy clusters: palaeontology with the MWA and ASKAP
Bartalucci, I.; Johnston-Hollitt, M.; Duchesne, S. W.
Galaxy clusters have been found to host a range of diffuse, non-thermal emission components, generally with steep, power law spectra. In this work we report on the detection and follow-up of radio halos, relics, remnant radio galaxies, and other fossil radio plasmas in Southern Sky galaxy clusters using the Murchison Widefield Array and the Austra…
Large-scale asymmetry in galaxy spin directions: evidence from the Southern hemisphere
Shamir, Lior
Recent observations using several different telescopes and sky surveys showed patterns of asymmetry in the distribution of galaxies by their spin directions as observed from Earth. These studies were done with data imaged from the Northern hemisphere, showing excellent agreement between different telescopes and different analysis methods. Here, da…
SPT-CL J2032-5627: A new Southern double relic cluster observed with ASKAP
Pratt, G. W.; Bartalucci, I.; Johnston-Hollitt, M. +2 more
We present a radio and X-ray analysis of the galaxy cluster SPT-CL J2032-5627. Investigation of public data from the Australian Square Kilometre Array Pathfinder (ASKAP) at 943 MHz shows two previously undetected radio relics at either side of the cluster. For both relic sources, we utilise archival Australia Telescope Compact Array (ATCA) data at…
Comparison of Gaia and Hipparcos parallaxes of close visual binary stars and the impact on determinations of their masses
Hussein, Abdallah M.; Al-Wardat, Mashhoor Ahmad; Al-Naimiy, Hamid M. +1 more
Precise measurement of the fundamental parameters of stellar systems, including mass and radius, depends critically on how well the stellar distances are known. Astrometry from space provides parallax measurements of unprecented accuracy, from which distances can be derived, initially from the Hipparcos mission, with a further refinement of that a…