| 22nd of May 2020 |
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| The intermittent pulsar J1841-0500 |
| by Wang et al. |
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Pulsars are rapdily rotating, highly magnetised neutron stars which
generate beams of radio emission. While most pulsars are always "on",
some pulsars display pulse nulling, in which the pulsed emission
ceases suddenly and then remains "off" for timescales of seconds to
hours or even days. The extreme case is intermittent pulsars, which
have "on" or "off" timescales which can last for years.
Studies of the first discovered intermittent pulsar,
PSR B1931+24, indicated that the pulsar rotation slows
down more slowly when it is in the "off" state than when it
is in the "on" state.
Wang et
al. present long-term observations of two intermittent pulsars, PSRs
J1832+0029 and J1841−0500 using the Parkes 64 m radio telescope.
The new observations have improved the determination of the
on-off timescales and the spin down rates during those emission
states. An unexpected signature was seen in the J1842-0500 data:
a quasi-periodic
fluctuation was identified in the intensities of the detectable single
pulses, with a modulation period between 21 and 36 pulse periods.
The image above shows the pulse frequency versus time (MJD = Modified Julian Day) for J1841-0500. The solid lines represent the pulse frequencies measured by phase-connected timing solutions. The dotted lines are the extrapolated pulse frequency when the pulsar was not detected. The lower panel is split into two. In the top the MJDs of the observations in which the pulsar was detected are shown. The bottom shows the MJDs for the new observations of this pulsar. The paper is accepted for publication in The Astrophysical Journal. |