Search

Measuring a pulsar's rotational evolution is crucial to understanding the nature of the pulsar. Here we provide updated timing models for the rotational evolution of six pulsars, five of which are rotation phase-connected using primarily NICER X-ray data. For the newly-discovered fast energetic young pulsar, PSR J0058-7218, we increase the baseline of its timing model from 1.4 days to 8 months and not only measure more precisely its spin-down rate nudot = (-6.2324+/-0.0001)x10^-11 Hz s^-1 but also for the first time the second time derivative of spin rate nuddot = (4.2+/-0.2)x10^-21 Hz s^-2. For the fastest and most energetic young pulsar, PSR J0537-6910 (with 16 ms spin period), we detect 4 more glitches, for a total of 15 glitches over 4.5 years of NICER monitoring, and show that its spin-down behavior continues to set this pulsar apart from all others, including a long-term braking index n = -1.234+/-0.009 and interglitch braking indices that asymptote to, 18 pages, 17 figures; accepted for publication in ApJ; very minor edits and no changes to numbers

The interpretation of pulsar rotational glitches, the sudden increase in spin frequency of neutron stars, is a half-century-old challenge. The common view is that glitches are driven by the dynamics of the stellar interior, and connect in particular to the interactions between a large-scale neutron superfluid and the other stellar components. This thesis is corroborated by observational data of glitches and the post-glitch response seen in pulsars’ rotation, which often involves very long timescales, from months to years. As such, glitch observables combined with consistent models incorporating the rich physics of neutron stars—from the lattice structure of their crust to the equation of state for matter beyond nuclear densities—can be very powerful at placing limits on, and reduce uncertainties of, the internal properties. This review summarises glitch observations, current data, and recent analyses, and connects them to the underlying mechanisms and microphysical parameters in the context of the most advanced theoretical glitch models to date.

We demonstrate that the high‐magnetic field pulsar J1119−6127 exhibits three different types of behaviour in the radio band. Trailing the “normal” profile peak there is an “intermittent” peak and these components are flanked by two additional components showing very erratic “RRAT‐like” emission. Both the intermittent and RRAT‐like events are extremely rare and are preceded by a large amplitude glitch in the spin‐down parameters. The post‐glitch spin‐down rate is smaller than the pre‐glitch rate, which is very unusual for the pulsar population as a whole, but is observed in the glitch recovery of a RRAT. If the abnormal radiative behaviour in PSR J1119−6127 is indeed glitch induced then there might exist a population of neutron stars which only become visible in the radio band for a short duration in the immediate aftermath of glitch activity. These neutron stars will be visible in the radio band as sources that only emit some clustered pulses every so many years.