A very large glitch in PSR B2334+61

TL;DR

This paper reports the observation of the largest ever glitch in PSR B2334+61, revealing detailed post-glitch behavior and internal neutron star effects over seven years of data.

Contribution

It presents the first detailed analysis of a very large pulsar glitch with exponential decay components and long-term spin-down rate changes.

Findings

Largest glitch ever observed in PSR B2334+61

Detected exponential decay with 21 and 147-day time constants

Identified a near one-year oscillation in post-glitch residuals

Abstract

Seven years of pulse time-of-arrival measurements have been collected from observations of the young pulsar PSR B2334+61 using the Nanshan radio telescope of Urumqi Observatory. A phase-connected solution has been obtained over the whole data span, 2002 August to 2009 August. This includes a very large glitch that occurred between 2005 August 26 and September 8 (MJDs 53608 and 53621). The relative increase in rotational frequency for this glitch, $\Delta\nu_{g}/\nu~\sim~20.5\times10^{-6}$, is the largest ever seen. Although accounting for less than 1\% of the glitch, there were two well-defined exponential decay terms with time constants of 21 and 147 days respectively. There was also a large long-term increase in the spindown rate with $\Delta\dot\nu_p/\dot\nu \sim 0.011$ at the time of the glitch. A highly significant oscillation with a period of close to one year is seen in the post-glitch residuals. It is very unlikely that this can be accounted for by a pulsar position error or proper motion -- it appears to result from effects interior to the neutron star. Implications of these results for pulsar glitch models are discussed.