PSR J1631−4722: the discovery of a young and energetic pulsar in the supernova remnant G336.7+0.5

ABSTRACT Detecting a pulsar associated with a supernova remnant (SNR) and/or pulsar wind nebula (PWN) is crucial for unraveling its formation history and pulsar wind dynamics, yet the association with a radio pulsar is observed only in a small fraction of known SNRs and PWNe. In this paper, we report the discovery of a young pulsar J1631−4722, associated with the Galactic SNR G336.7$+$0.5 using Murriyang, Commonwealth Scientific and Industrial Research Organisation (CSIRO)’s Parkes radio telescope. It is also potentially associated with a PWN revealed by the Rapid ASKAP (Australian Square Kilometre Array Pathfinder) Continuum Survey (RACS). This 118 ms pulsar has a high dispersion measure of $\sim$873 pc cm$^{-3}$ and a rotation measure of –1004 rad m$^{-2}$. Because of such a high DM, at frequencies below 2 GHz, the pulse profile is significantly scattered, making it effectively undetectable in previous pulsar surveys at $\sim$1.4 GHz. Follow-up observations yield a period derivative of $\dot {P} = 5.5\times 10^{-14}$, implying a characteristic age, $\tau _{\mathrm{ c}} = 33.9$ kyr, and spin-down luminosity, $\dot {E} = 1.3\times 10^{36}$ erg s$^{-1}$. PSR J1631−4722, with its high spin-down luminosity and potential link to a PWN, stands out as a promising source of the high-energy $\gamma$-ray emission observed in the region.