Size-waiting-time Correlations in Pulsar Glitches

Abstract

Few statistically compelling correlations are found in pulsar timing data between the size of a rotational glitch and the time to the preceding glitch (backward waiting time) or the succeeding glitch (forward waiting time), except for a strong correlation between sizes and forward waiting times in PSR J0537-6910. This situation is counterintuitive if glitches are threshold-triggered events, as in standard theories (e.g., starquakes, superfluid vortex avalanches). Here, it is shown that the lack of correlation emerges naturally, when a threshold trigger is combined with secular stellar braking slower than a critical, calculable rate. The Pearson and Spearman correlation coefficients are compu..