Showing results for: [ Norris, Ray ]
These observations will form part of the ASKAP pilot survey program. This is a joint exercise between CASS and the ASKAP Survey Science Teams to conduct a series of observations to learn how to conduc... moret large-scale surveys using the full capabilities of this new telescope. The key goal of the pilot survey program is to establish readiness for full survey operations, including determining and testing observing and processing strategies, and data validation and release. The observations collected here are primarily for EMU.less
Australia Square Kilometre Array Pathfinder - AS101 - ASKAP Pilot Survey for EMU - Published 09 Aug 2019
These data are a combined mosaic of two overlapping ASKAP tiles covering the GAMA-23 field.
The following is copied from the validation notes of the source SBIDs and also apply to these data.
These ... moredata represent a test observation with the full ASKAP array. While it may be useful for science purposes the primary goal of the release is to seek feedback on data quality from the science community. Although the image approaches expected noise levels in most areas, a common feature of early ASKAP data has been some low-level artefacts (at ~1%) very close to bright sources (a few hundred mJy and above). These artefacts generally appear as radial stripes and rapidly fade away from the source. The origin of these artefacts is yet to be determined, but they do not seem to emulate any known instrumental effect taken into account in commonly used wideband/widefield calibration and imaging software packages (such as ASKAPsoft, casa etc.). The spectral indices given in the catalogues were derived from Taylor-term imaging, which is a technique not yet widely used in radio astronomy. It has been identified that the distribution of the spectral indices in these catalogues deviates significantly from expectations for reasons that are not yet understood. Fitting spectra to sources in the continuum cubes is recommended to attain more reliable spectral indices. While the commissioning team investigates the cause of these issues in detail, we do not wish to hold the release of otherwise good quality data. Hence these test observations are being released, but with the validation flag set to “uncertain” — meaning user discretion is necessary in the interpretation for science purposes. Users should perform their own analysis of the flux scale, source positions and spectral indices given. The ASKAP operations team would be glad to receive feedback on any issues discovered.less
Australia Square Kilometre Array Pathfinder - AS034 - ASKAP Early Science Broadband Survey - Published 19 Jun 2019
We propose to carry out a wideband (approximately 700 -1800 MHz) early science survey in full polarisation mode with at least 12 antennas of the Australian SKA Pathfinder (ASKAP) telescope. We will be... moregin with a small pilot program (starting with a smaller number of telescopes and possibly a smaller bandwidth) in order to test and prepare software required to carry out the full survey. These data will serve the EMU, POSSUM, FLASH and VAST survey teams.less
Australia Square Kilometre Array Pathfinder - AS034 - ASKAP Early Science Broadband Survey - Published 27 Sep 2018
ATLAS is a project to image seven square degrees of sky, in two fields (CDF-S and ELAIS-S1), at radio wavelengths, to an rms of about 15 µJy, making it the widest deep radio survey aver attempted. The... more fields are chosen to cover the Spitzer Wide-Area IR Extragalactic Survey (SWIRE), and the radio images cut through the dust, to trace the cosmic history of AGN and star-forming galaxies.
Data release 1 contains two catalogues from the deep ATLAS radio observations of the CDFS-SWIRE field:
1) radio components; and
2) radio sources with their identifications and classifications
Australia Square Kilometre Array Pathfinder - C1967 - The ATLAS 1.4 GHz survey - Published 24 Mar 2016
CU Virginis is the prototypical example of a new class of stellar radio transient. This star provides a unique laboratory for studying coherent radio emission mechanisms in a stellar environment. Obs... moreervations taken for this proposal will allow us to determine whether the pulses are formed out a continuous emission process or discrete flares and thereby constrain the emission mechanism.less
Australia Telescope National Facility - P741 - High time resolution observations of CU Virginis - Published 24 Jul 2014
The Australia Telescope Large Area Survey (ATLAS) team have surveyed seven square degrees of sky at 1.4GHz. During processing some unexpected infrared-faint radio sources (IFRS sources) were discover... moreed. The nature of these sources is not understood, but it is possible that some of these sources may be pulsars within our own galaxy. We propose to observe the IFRS sources with steep spectral indices using standard search techniques to determine whether or not they are pulsars. A pulsar detection would 1) remove a subset of the IFRS sources from the ATLAS sample so they would not need to be observed with large optical/IR telescopes to find their hosts and 2) be intrinsically interesting as the pulsar would be a millisecond pulsar and/or have an extreme spatial velocity.less
Australia Telescope National Facility - P676 - Do the enigmatic ``Infrared-Faint Radio Sources'' include pulsars? - Published 04 Sep 2013