Discovery of an RRAT-like pulsar via its single pulses in an MWA imaging survey

Abstract

We report the discovery of PSR J0031$-$5726 in the GaLactic and Extragalactic All-sky MWA eXtended imaging survey at a Galactic latitude of $b\approx -60^{\circ }$. The pulsar exhibits both sporadic, extremely bright pulses reminiscent of rotating radio transients (RRATs) as well as a persistent, dimmer pulses. The bright pulses tend to arrive at later rotation phases than their dimmer counterparts, and have dramatically varying polarization angle curves, such that the integrated profile appears almost completely depolarized down to the system noise level. The rotation measure of individual pulses was found to sometimes vary by up to $\sim 0.8$rad/m${}^2$, but was otherwise generally consistent with its average (ionosphere-corrected) value of $10.0\pm 0.1$rad/m${}^2$. We surmise that J0031$-$5726 may represent a class of pulsar that is intermediate between normal pulsars and RRATs.

16 pages, 6 figures, accepted for publication in ApJ