Generating quasi-periodic pulsar glitches using a state-dependent Poisson process

Glitching pulsars fall broadly into two statistical classes: those with Poisson-like waiting times and power-law sizes, and those with unimodal waiting times and sizes. Previous glitch modelling based on a state-dependent Poisson process readily generates Poisson-like behaviour but struggles to produce unimodal waiting times or sizes. Here it is shown that, when some of the inputs to the model are modified, both classes of statistical behaviour can be reproduced by varying a single control parameter related to the spin-down rate. The implications for past and future glitch observations and the underlying microphysical mechanism are explored briefly.