The
ASKAP
update for August reports on
maintenance activities, efforts to improve pipeline performance and image quality,
and some of the interesting features found during data validation efforts.
Investigation continues into imaging artefacts introduced by the Sun,
which is a powerful radio source usually located far from the field centre.
As solar activity increases, we are also noticing time-dependent
emission from hot spots within the solar disk, offset from its
centre. These bright outbursts are much stronger than the Sun’s
quiescent emission and are difficult to characterise for mitigation
purposes due to their variable nature. They are also more compact and
spread the Sun's influence over a wider range of spatial scales.
The image above shows data from a recent science observation re-phased in the
direction of the Sun (which was well oustide the ASKAP field of view and
is detected through the telescope's sidelobes).
The solar disk is outlined in yellow.
A bright compact hot spot on the Sun's disk appears in the image with significant
bandwidth smearing due to its distance from the phase tracking
centre. Efforts to deal with the variable emission from such spots is ongoing.
(Image credit: Emil Lenc)
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