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The globular cluster Omega Centauri is the most massive and luminous
cluster in the Galaxy. The Fermi gamma-ray source FL8Y J1326.7-4729 is
coincident with the core of the cluster, leading to speculation that
hitherto unknown radio pulsars or annihilating dark matter may be
present in the cluster core. Dai et al. have recently discovered five
millisecond pulsars in Omega Centauri with the Parkes radio
telescope. Four of these pulsars are isolated with spin periods of
4.1, 4.2, 4.6 and 6.8 ms. The fifth has a spin period of 4.8 ms and is
in an eclipsing binary system with an orbital period of 2.1 hours. It
is considered highly likely that the millisecond pulsars are the
source of the gamma-ray emission. The long-term timing of these
pulsars opens up opportunities to explore the dynamics and
interstellar medium of the cluster. The figure above shows deep ATCA
2.1 GHz images of the cluster centre (yellow circle), overlaid with
two pulsars with timing solutions (blue stars), unidentified X-ray
sources (red circles) and the Fermi source (blue circle). More
details are given in
the preprint of the paper
which will be published in the Astrophysical Journl.
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