15th of June 2021 |
---|
![]() |
A glitch in the pulsar PSR J1452-6036 |
by Jankowski et al. |
Pulsar glitches are sudden spin-up events that occur in radio pulsars.
Over 550 glitches have been catalogued, in 190 individual pulsars,
with roughly 7% of known pulsars having displayed a glitch, although
the actual fraction might be significantly higher because of
observational bias. Initially thought to be the observational results
of the cracking of the neutron star’s crust in so-called star-quakes,
the commonly accepted theory now is that they represent catastrophic
unpinning events of vortices in the neutron star’s superfluid
interior, that had previously been held in place by the star’s strong
magnetic field
Jankowski et al. present multi-epoch wide-band observations the radio pulsar J1452-6036, taken before and, serendipitously, shortly after a glitch occurred on 2019 April 27. The data from their third observing session with the Parkes Ultra-wide Band Low receiver (704-4032 MHz) began 3 h after the best-fitting glitch epoch, which they constrained to within ∼4 min. The glitch was of intermediate size, with a fractional change in spin frequency of 2.7×10-7. The pulsar's spectral index, spectral shape, polarization fractions, and rotation measure stayed constant within the uncertainties across the glitch epoch. However, its pulse-averaged flux density increased significantly by about 10 per cent in the post-glitch epoch and decayed slightly before our fourth observation a day later. The image above shows timing residuals of PSR J1452−6036 around the glitch epoch. Data from Parkes are plotted in blue, and data from the Molonglo telescope in orange. The results have been published in Monthly Notices of the Royal Astronomical Society. |