The TRAPUM Small Magellanic Cloud pulsar survey with MeerKAT - II. Nine new radio timing solutions and glitches from young pulsars

Abstract

We report new radio timing solutions from a 3-yr observing campaign conducted with the MeerKAT and Murriyang telescopes for nine Small Magellanic Cloud pulsars, increasing the number of characterized rotation-powered extragalactic pulsars by 40 per cent. We can infer from our determined parameters that the pulsars are seemingly all isolated, that six are ordinary pulsars, and that three of the recent MeerKAT discoveries have a young characteristic age of under 100 kyr and have undergone a spin-up glitch. Two of the sources, PSRs J00407337 and J00487317, are energetic young pulsars with spin-down luminosities of the order of 1036 erg s-1. They both experienced a large glitch, with a change in frequency of about 30 μHz, and a frequency derivative change of order -10-14Hz s-1. These glitches, the inferred glitch rate, and the properties of these pulsars (including potentially high inter-glitch braking indices) suggest these neutron stars might be Vela-like repeating glitchers and should be closely monitored in the future. The position and energetics of PSR J00487317 confirm it is powering a new pulsar wind nebula (PWN) detected as a radio continuum source; and similarly the association of PSR J00407337 with the PWN of supernova remnant (SNR) DEM S5 (for which we present a new Chandra image) is strengthened. Finally, PSR J00407335 is also contained within the same SNR but is a chance superposition. It has also been seen to glitch with a change of frequency of Hz. This work more than doubles the characterized population of SMC radio pulsars.