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Ap stars are peculiar A-type stars, which generally have higher
magnetic fields, higher abundances of metals, and rotate more slowly
thtan regular A-type stars. KQ Vel is an optically bright Ap star
system estimated to be only about 260 million years old (compared to
the Sun's age of 4.6 billion years) and lying about 520 light years
away. Optical observations indicate a rotation period of around 7.7
years (compared to the Sun's 26 days!).
Leto et al. have recently reported the detection of radio emission from
Kq Vel, using ATCA observations in the 16cm, 4cm, and 15mm bands.
The most obvious explanation for the radio emission is that it
originates in the magnetosphere of the Ap star, but this is shown to
be unfeasible as the predicted radio luminosity for this model is more
than 100,000 times lower than the measured one. The authors favour an
alternative model involving the companion star (of as yet unknown
type) which orbits the Ap star every ~840 days. The plots above show
the detections of the KQ Vel system at four frequencies. The
elliptical synthesized beams of the ATCA from these observations are
shown in the bottom-left corner of each plot.
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