Parkes observations for project P1005 semester 2019APRS_01

We propose to conduct observations of PSRs J1812-15 and J1831-04, a pair of 1-s pulsars which exhibit both nulling behaviour and clear evidence of acceleration, suggesting that they are in binary systems. Binary pulsars are valuable objects of scientific study, allowing for a wide range of applications, including tests of gravity, probes of the neutron star equation of state and fossil records of stellar evolution. Long spin-period pulsars in binary systems are generally much rarer than faster-spinning recycled pulsars, and represent an under-explored region of pulsar binary evolution.\r\n\r\nDue to the nulling behaviour of both PSRs J1812-15 and J1831-04, determination of an orbital or phase-connected solution has so far proved impossible, but both of these steps are vital in allowing for their continued study. We propose a targeted, high-cadence observing campaign designed to map the orbits of these pulsars while simultaneously factoring in the redundancy required in order to overcome their nulling behaviour. By studying these pulsars, we hope to provide new insight into an unusual class of pulsar binary, as well to constrain the nulling properties of both pulsars.