Hodgson et al. have used the MWA and ASKAP
to follow up 28 candidate large-scale diffuse synchrotron sources
previously reported as possible detections of filaments of the
synchrotron cosmic web.
They show that lower frequency observations, and in particular those by
ASKAP, are ideally suited to detect large-scale, extended synchrotron
emission (but conclude that none of the 28
sources are likely to be associated with the cosmic web).
As a demonstration of the capabilities of ASKAP and the MWA,
Hodgson et al. present the above image of a radio galaxy in the same field.
The colour-scale image is from ASKAP data centred at 887 MHz, with the
white contours from the MWA (phase 2 array) centred at 154 MHz.
In contrast to the example in an ADAP earlier this week,
the two radio lobes of the galaxy
are detected by both telescopes, with the radio core not detected by
either telescope.
The peaks of the MWA emission are offset from the ASKAP peaks due to
differences in spectral indices of the bright hotspots visible in the ASKAP
image and the jet and lobe emission closer to the core, and the angular resolutions
of the two telescopes.
The paper will be published in
Publications of the Astronomical Society of Australia.
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