Astronomer tags ASKAP as the best instrument in the world for finding FRB’s
Australian astronomers have found a ‘fast radio burst’ (FRB) after searching for only three and half days, using eight of ASKAP’s 36 dishes. FRB170107 was found as part of the CRAFT research project (Commensal Real-time ASKAP Fast Transients survey), which is led by CSIRO’s Dr Keith Bannister and Dr Jean-Pierre Macquart from the Curtin University node of ICRAR.
‘Fast radio bursts’ or FRBs are short, sharp spikes of radio waves lasting a few milliseconds. They appear to come from powerful events billions of light-years away but their cause is still a mystery. The first was discovered in 2007 and only two dozen have been found since.
Since January the team has continued to observe regularly (with less than 10 antennas), in parallel to array commissioning activities and have discovered three more FRBs at a range of implied distances.
Dr Bannister and his team expect to find one every two to three days when they are using 12 dishes and he says ASKAP is the best radio telescope in the world for finding FRBs.
To find the burst, the researchers used an unusual strategy, pointing each dish in a slightly different direction, like the segments of a fly’s eye. This multiplies the amount of sky the telescope can see. Eight ASKAP dishes can see 240 square degrees at once – about a thousand times the area of the full Moon.
The next step will be to determine the exact location of the FRBs and the team plans to continue with the fly’s eye observing. They are also looking forward to commensal interferometric observations in 2018, which will give ASKAP precise locations for every FRB it detects; resolving one of the key observational questions in FRB astrophysics.
ASKAP early science
ASKAP commissioning and science teams have released the first images and source catalogues derived from observations made at the beginning of the early science programme in October 2016. These observations were made with a subset of 12 antennas equipped with entirely new second generation phased array feed systems and the release marks the first time that data from these systems have been publicly released.
The observations cover a total area of about 40 square degrees, which is more than 200 times the size of the full moon. To image such a large area of sky, we used all 36 of the ASKAP beams simultaneously in a 6×6 square grid.
These observations were recorded to disk at the Pawsey Supercomputing Centre, where they were reprocessed several times to adjust the settings of our science data pipeline. In the process of making these adjustments, the team also developed a set of quality metrics that can be used to assess how well the imaging software performs – these include comparing the detected source positions and fluxes to existing catalogues at similar wavelengths. This first science data set was produced with the ASKAP science data processing software named ASKAPsoft, running in the dedicated Supercomputer at Pawsey.
This release is particularly significant because it marks the first time that a large data set has been uploaded to the CSIRO ASKAP Science Data Archive (CASDA), the final destination for all ASKAP observations. The data archive (https://data.csiro.au) is itself a complex software project that has undergone extensive internal testing.
In addition, astronomer Josh Marvil has put together a composite image using all the released data, which can be interactively explored using the Aladin sky viewer. This image shows ASKAP data as a grey-scale intensity map, with the primary beam coverage from two different field centres shown as coloured circles and the positions of known radio sources plotted as blue squares for comparison.
ASKAP PAF Production on Schedule for Completion
CSIRO is commencing work on its final phased array feeds (PAF) and digital systems for ASKAP as PAF # 40 rolls onto the production line. The total production run included 38 Mk II PAFs to fit the 36 ASKAP antennas at the MRO, with two spares (to minimise downtime during maintenance) and another two for contracts with the Max Planck Institute (MPI) Germany and Jodrell Bank, UK.
MPI installed the PAF in April, after it spent eight months at CSIRO’s Parkes Observatory for commissioning and early science test observations. The Jodrell Bank PAF is scheduled for shipping.
The photo below shows recent filming at Puzzle Precision, CSIRO’s industry partner, where the high end electronics and digital back end hardware for ASKAP has been produced. Filming is also taking place at CSIRO’s Marsfield site to document the entire production and assembly process. The video will highlight how science innovation is supporting industry innovation and growth.
Parkes SKA Pathfinder Update
Since the last issue, further progress has been made on the development of the new Ultra-Wideband receiver (700 MHz to 4 GHz), with the preliminary build of the receiver coming together and due for on-dish testing in early August, the results of which are intended for presentation at the URSI GASS meeting later in the month.
The funding proposal for the cryogenically cooled PAF on Parkes to the Australian Research Council is currently under review, with a decision expected November 2017.
ASKAP Welcomes Ministerial Visit to the MRO
Australia’s Minister for Industry, Innovation and Science, Senator the Hon Arthur Sinodinos, and the state of Western Australia’s Minister for Water, Fisheries, Forestry, Innovation and ICT, and Science, The Hon Dave Kelly MLA, were honoured guests at CSIRO’s Murchison Radio-astronomy Observatory (MRO) on Wednesday 2 August 2017. The ministers toured the MRO accompanied by other VIPs from Western Australia and CSIRO’s Chief Executive Dr Larry Marshall.
SKA Board Member and CSIRO Astronomy and Space Science Deputy Director, Dr Sarah Pearce, said the visitors enjoyed the opportunity to see ASKAP, MWA and the other demonstrator technologies across the MRO, which is the future site for the SKA in Australia.