The largest glitch observed in the Crab pulsar

Benjamin Shaw, Andrew Lyne, Benjamin Stappers, Patrick Weltevrede, Cees Bassa, Amy Lien, Mitchell Mickaliger, Rene Breton, Christine Jordan, Michael Keith, Hans Krimm

    Research output: Contribution to journalArticlepeer-review

    108 Downloads (Pure)


    We have observed a large glitch in the Crab pulsar (PSR B0531+21). The glitch occurred around MJD 58064 (2017 November 8) when {the pulsar underwent an increase in the rotation rate of $\Delta \nu = 1.530 \times 10^{-5}$ Hz, corresponding to a fractional increase of $\Delta \nu / \nu = 0.516 \times 10^{-6}$} making this event the largest glitch ever observed in this source. Due to our high-cadence and long-dwell time observations of the Crab pulsar we are able to partially resolve a fraction of the total spin-up of the star. This delayed spin-up occurred over a timescale of $\sim$1.7 days and is similar to the behaviour seen in the 1989 and 1996 large Crab pulsar glitches. The spin-down rate also increased at the glitch epoch by $\Delta \dot{\nu} / \dot{\nu} = 7 \times 10^{-3}$. In addition to being the largest such event observed in the Crab, the glitch occurred after the longest period of glitch inactivity since at least 1984 and we discuss a possible relationship between glitch size and waiting time. No changes to the shape of the pulse profile were observed near the glitch epoch at 610 MHz or 1520 MHz, nor did we identify any changes in the X-ray flux from the pulsar. The long-term recovery from the glitch continues to progress as $\dot{\nu}$ slowly rises towards pre-glitch values. In line with other large Crab glitches, we expect there to be a persistent change to $\dot{\nu}$. We continue to monitor the long-term recovery with frequent, high quality observations.
    Original languageEnglish
    Pages (from-to)3832–3840
    Number of pages8
    JournalMonthly Notices of the Royal Astronomical Society
    Issue number3
    Early online date17 May 2018
    Publication statusPublished - 21 Aug 2018


    Dive into the research topics of 'The largest glitch observed in the Crab pulsar'. Together they form a unique fingerprint.

    Cite this