Trois ratés dans un pulsar jusque-là silencieux ✛

Résumé original

tel que rédigé par les auteurs, en anglais arXiv:2608.19555v1

We present the discovery and analysis of three rotational glitches in the young pulsar PSR J1637$$-$$4642. The timing observations span from 19 February 2009 to 6 October 2024 (MJD 54881$$-$$60589) from the Murriyang radio telescope of the Parkes Observatory. The first and strongest glitch occurred around MJD 58352 with a fractional frequency change of $$\Delta u/ u \sim 2.7 \times 10^{-6}$$, while two additional smaller glitches were detected at MJD 59443 and MJD 60445 with fractional changes of $$2.2 \times 10^{-9}$$ and $$2.8 \times 10^{-8}$$, respectively. Prior to this, the pulsar had shown no glitch activity since its discovery in the Parkes Multibeam survey. Only the first glitch exhibits detectable exponential recovery, with a decay timescale of $$\sim$$100 days and a small recovery fraction $$\approx 0.015$$, accompanied by a permanent increase in the magnitude of the spin-down rate. Modeling the post-glitch evolution of $$\dot{ u}$$ within the vortex-creep framework using Bayesian inference gives a superfluid moment-of-inertia fraction $$\approx 0.0187$$, consistent with the inner-crust superfluid. These results reinforce the standard superfluid glitch paradigm and demonstrate that even ``quiet'' pulsars can still host substantial glitch activity.