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Last month
one of the first SKA-Low tiles was used to make a movie of the radio sky
over the course of a day. Last week there was further progress, with the
first interferometric fringes obtained between two SKA-Low stations.
The two stations were S8-1 and S8-6, which are separated by 122m.
Station beam-forming was done using the Sun, and the plot
shown here were made as a bright radio source drifted through the beam as the Earth rotated.
The "waterfall" plot shows colour-coded interferometer phase as a function of
frequency (on the x-axis) and time (on the y-axis), with 20 minutes of data plotted.
A 6 MHz bandwidth was used for processing convenience, the
radio source was bright and the signal-to-noise ratio was not an issue.
The X- and Y-polarisations are the orthogonal responses from the
log-periodic crossed-dipole antennas.
There is a strong XY response because the two stations
are rotated by about 60 degrees with respect to each other.
(Image credit: Alex Hill)
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