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arXiv · 2206.00805

Independent discovery of a nulling pulsar with unusual sub-pulse drifting properties with the Murchison Widefield Array

Samuel J. McSweeney·N. D. Ramesh Bhat·Nicholas A. Swainston·Keegan R. Smith·Sanjay Kudale·Paul Hancock·Willem van Straten·Shi Dai·Ryan M. Shannon·Steven J. Tingay·Melanie Johnston-Hollitt·David L. Kaplan·Mia Walker
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Abstract

We report the independent discovery of PSR J0027-1956 with the Murchison Widefield Array (MWA) in the ongoing Southern-sky MWA Rapid Two-meter (SMART) pulsar survey. J0027-1956 has a period of ~1.306 s, a dispersion measure (DM) of ~20.869 pc cm^-3 , and a nulling fraction of ~77%. This pulsar highlights the advantages of the survey's long dwell times (~80 min), which, when fully searched, will be sensitive to the expected population of similarly bright, intermittent pulsars with long nulls. A single-pulse analysis in the MWA's 140-170 MHz band also reveals a complex sub-pulse drifting behavior, including both rapid changes of the drift rate characteristic of mode switching pulsars, as well as a slow, consistent evolution of the drift rate within modes. In some longer drift sequences, interruptions in the otherwise smooth drift rate evolution occur preferentially at a particular phase, typically lasting a few pulses. These properties make this pulsar an ideal test bed for prevailing models of drifting behavior such as the carousel model.

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Samuel J. McSweeney, N. D. Ramesh Bhat, Nicholas A. Swainston, Keegan R. Smith, Sanjay Kudale, Paul Hancock, Willem van Straten, Shi Dai, Ryan M. Shannon, Steven J. Tingay, Melanie Johnston-Hollitt, David L. Kaplan, Mia Walker. 2022-06-02. Independent discovery of a nulling pulsar with unusual sub-pulse drifting properties with the Murchison Widefield Array. https://doi.org/10.3847/1538-4357%2Fac75bc

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