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Duchesne et al. present new low-frequency (88--216 MHz)
Murchison Widefield Array (MWA) observations of the complex merging galaxy cluster Abell 3266
and combine these with ASKAP RACS-low data.
They detect four steep spectrum extended radio sources within the cluster.
They confirm the detection of a ∼570 kpc radio relic to the
south of the cluster, and a possible bridge of emission connecting the relic to the cluster core.
They also detect two new ultrasteep–spectrum fossil plasma sources to the north and west of the
cluster centre without associated compact radio emission.
A previously detected radio galaxy (RG) in the cluster is also found to have a
spectrally steepening tail with steep-spectrum components highlighted by the MWA.
No giant radio halo is detected in the cluster. Why a giant radio halo is undetected in
Abell 3266 is unclear -- the timeline of the merger and overall mass of the system as
determined by optical and X-ray studies
suggest the foundation for a hosting system.
The background image above (and black contours) is Abell 3266 at 216 MHz.
The overlaid contours in yellow are the re-imaged RACS data,
and the purple contours are from the smoothed, exposure-corrected XMM-Newton image.
Sources of interest are labelled. The framed ellipses in the lower left and top
right are the shapes of restoring beams for the MWA-2 and RACS images, respectively.
The paper will be published in
Monthly Notices of the Royal Astronomical Society.
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