Pulsar Glitch Behaviour and AXPs, SGRs and DTNs

Large pulsar glitches seem to be common to all radio pulsars and to exhibit a universal behaviour connecting the rate of occurrence, event size and interglitch relaxation that can be explained if the glitches are due to angular momentum exchange in the neutron star. This has implications for the energy dissipation rate. The large timing excursions observed in SGRs are not similar to the pulsar glitches. The one glitch observed in an AXP is very similar to pulsar glitches and demonstrates that typical neutron star glitch response occurs when the external torque is constant for an extended period of time. In the long run the timing variations of both the AXPs and the SGRs are much stronger than the timing noise of radio pulsars but comparable with the behaviour of accreting sources. For the DTNs, the thermal luminosities do not seem compatible with cooling ages and statistics if these sources are magnetars. The energy dissipation rates implied by the dynamical behaviour of glitching pulsars will provide the luminosities of the DTNs under propeller spindown torques supplied by fossil disks on neutron stars with conventional 10 G dipole magnetic fields. 1. The Signature of Large Pulsar Glitches A simple model detailed first for the Vela pulsar’s glitches pictures the glitches as the discrete component of angular momentum exchange between the observed crust and other components of the neutron star (Alpar et al. 1993 and references therein). There is also a continuous part of the angular momentum exchange between the components. It is believed that the interior of the neutron star is superfluid, which means that the angular momentum is transported by discrete carriers, the quantized vortices of the superfluid. There is a simple analogy with an electronic circuit that contains resistive as well as capacitive elements. The parts of the superfluid where there is a continuous vortex current that allows the superfluid to take part in the spindown are the resistive elements, where continuous energy dissipation accompanies the angular momentum transport. Say these resistive parts have total moment of inertia IA. The resistive parts may be disjoint regions within which there is a vortex density and vortex current. Some of these vortices may be trapped by pinning centers. The resistive parts collectively are the analogues of capacitor ’plates’ and the wires connecting them in an electronic circuit. These resistive regions are separated by vortex free regions, analogues of the space between capacitor plates. The glitches are