Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Rotational evolution of the Vela pulsar during the 2016 glitch

Nature Astronomy volume 3, pages 1143–1148 (2019)Cite this article

Subjects

Abstract

The 2016 Vela glitch observed by the Mount Pleasant radio telescope provides the first opportunity to study pulse-to-pulse dynamics of a pulsar glitch, opening up new possibilities to study the neutron star’s interior. We fit models of the star’s rotation frequency to the pulsar data, and present the following three results. First, we constrain the glitch rise time to less than 12.6 s with 90% confidence, almost three-times shorter than the previous best constraint. Second, we find definitive evidence for a rotational-frequency overshoot and fast relaxation following the glitch. Third, we find evidence for a slowdown of the star’s rotation immediately before the glitch. The overshoot is predicted theoretically by some models; we discuss implications of the glitch rise and overshoot decay times on internal neutron-star physics. The slowdown preceding the glitch is unexpected; we propose the slowdown may trigger the glitch by causing a critical lag between crustal superfluid and the crust.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Rotational frequency evolution.
Fig. 2: Posterior distribution p(τr) for the glitch rise time, τr.
Fig. 3: Rotational frequency evolution of the data (black and grey reproduced from Fig. 1) and best-fit models.
Fig. 4: Posterior for overshoot–decay parameters in the H2+p model, corresponding to the red curves in Fig. 3.
Fig. 5: Posterior for precursor parameters in the H2+p model, corresponding to the red curves in Fig. 3.

Similar content being viewed by others

Data availability

The data used in this work are available from ref. 2.

Code availability

The bilby19 analysis code is available from https://git.ligo.org/lscsoft/bilby and particular scripts for this analysis are available on request from the authors.

References

  1. Anderson, P. W. & Itoh, N. Pulsar glitches and restlessness as a hard superfluidity phenomenon. Nature 256, 25–27 (1975).

    Article  ADS  Google Scholar 

  2. Palfreyman, J., Dickey, J. M., Hotan, A., Ellingsen, S. & van Straten, W. Alteration of the magnetosphere of the Vela pulsar during a glitch. Nature 556, 219–222 (2018).

    Article  ADS  Google Scholar 

  3. Dodson, R. G., McCulloch, P. M. & Lewis, D. R. High time resolution observations of the January 2000 glitch in the Vela pulsar. Astrophys. J. Lett. 564, L85–L88 (2002).

    Article  ADS  Google Scholar 

  4. Dodson, R., Lewis, D. & McCulloch, P. Two decades of pulsar timing of Vela. Astrophys. Space Sci. 308, 585–589 (2007).

    Article  ADS  Google Scholar 

  5. van Eysden, C. A. & Melatos, A. Pulsar glitch recovery and the superfluidity coefficients of bulk nuclear matter. Mon. Not. R. Astron. Soc. 409, 1253–1268 (2010).

    Article  ADS  Google Scholar 

  6. Haskell, B., Pizzochero, P. M. & Sidery, T. Modelling pulsar glitches with realistic pinning forces: a hydrodynamical approach. Mon. Not. R. Astron. Soc. 420, 658–671 (2012).

    Article  ADS  Google Scholar 

  7. Antonelli, M. & Pizzochero, P. M. Axially symmetric equations for differential pulsar rotation with superfluid entrainment. Mon. Not. R. Astron. Soc. 464, 721–733 (2017).

    Article  ADS  Google Scholar 

  8. Graber, V., Cumming, A. & Andersson, N. Glitch rises as a test for rapid superfluid coupling in neutron stars. Astrophys. J. 865, 23 (2018).

    Article  ADS  Google Scholar 

  9. Ruderman, M. Crust-breaking by neutron superfluids and the Vela pulsar glitches. Astrophys. J. 203, 213–222 (1976).

    Article  ADS  Google Scholar 

  10. Cheng, K. S., Alpar, M. A., Pines, D. & Shaham, J. Spontaneous superfluid unpinning and the inhomogeneous distribution of vortex lines in neutron stars. Astrophys. J. 330, 835–846 (1988).

    Article  ADS  Google Scholar 

  11. Alpar, M. A., Chau, H. F., Cheng, K. S. & Pines, D. Postglitch relaxation of the Crab pulsar: evidence for crust cracking. Astrophys. J. 427, L29 (1994).

    Article  ADS  Google Scholar 

  12. Andersson, N., Comer, G. L. & Prix, R. Are pulsar glitches triggered by a superfluid two-stream instability? Phys. Rev. Lett. 90, 091101 (2003).

    Article  ADS  Google Scholar 

  13. Glampedakis, K. & Andersson, N. Hydrodynamical trigger mechanism for pulsar glitches. Phys. Rev. Lett. 102, 141101 (2009).

    Article  ADS  Google Scholar 

  14. Peralta, C., Melatos, A., Giacobello, M. & Ooi, A. Transitions between turbulent and laminar superfluid vorticity states in the outer core of a neutron star. Astrophys. J. 651, 1079–1091 (2006).

    Article  ADS  Google Scholar 

  15. Warszawski, L. & Melatos, A. Knock-on processes in superfluid vortex avalanches and pulsar glitch statistics. Mon. Not. R. Astron. Soc. 428, 1911–1926 (2013).

    Article  ADS  Google Scholar 

  16. Andersson, N., Glampedakis, K. & Hogg, M. Superfluid instability of r-modes in ‘differentially rotating’ neutron stars. Phys. Rev. D 87, 063007 (2013).

    Article  ADS  Google Scholar 

  17. Hobbs, G. B., Edwards, R. T. & Manchester, R. N. TEMPO2, a new pulsar-timing package—I. An overview. Mon. Not. R. Astron. Soc. 369, 655–672 (2006).

    Article  ADS  Google Scholar 

  18. Edwards, R. T., Hobbs, G. B. & Manchester, R. N. TEMPO2, a new pulsar timing package—II. The timing model and precision estimates. Mon. Not. R. Astron. Soc. 372, 1549–1574 (2006).

    Article  ADS  Google Scholar 

  19. Ashton, G. et al. BILBY: a user-friendly Bayesian inference library for gravitational-wave astronomy. Astron. Astrophys. J. Suppl. Ser. 241, 27 (2019).

    Article  ADS  Google Scholar 

  20. Buchner, J. et al. X-ray spectral modelling of the AGN obscuring region in the CDFS: Bayesian model selection and catalogue. Astron. Astrophys. 564, A125 (2014).

    Article  Google Scholar 

  21. Feroz, F. & Hobson, M. P. Multimodal nested sampling: an efficient and robust alternative to Markov chain Monte Carlo methods for astronomical data analyses. Mon. Not. R. Astron. Soc. 384, 449–463 (2008).

    Article  ADS  Google Scholar 

  22. Feroz, F., Hobson, M. P. & Bridges, M. MULTINEST: an efficient and robust Bayesian inference tool for cosmology and particle physics. Mon. Not. R. Astron. Soc. 398, 1601–1614 (2009).

    Article  ADS  Google Scholar 

  23. Sidery, T., Passamonti, A. & Andersson, N. The dynamics of pulsar glitches: contrasting phenomenology with numerical evolutions. Mon. Not. R. Astron. Soc. 405, 1061–1074 (2010).

    ADS  Google Scholar 

  24. Alpar, M. A., Langer, S. A. & Sauls, J. A. Rapid postglitch spin-up of the superfluid core in pulsars. Astrophys. J. 282, 533–541 (1984).

    Article  ADS  Google Scholar 

  25. Mendell, G. Superfluid hydrodynamics in rotating neutron stars. I—nondissipative equations. II—dissipative effects. Astrophys. J. 380, 515–540 (1991).

    Article  ADS  MathSciNet  Google Scholar 

  26. Andersson, N., Sidery, T. & Comer, G. L. Mutual friction in superfluid neutron stars. Mon. Not. R. Astron. Soc. 368, 162–170 (2006).

    Article  ADS  Google Scholar 

  27. Kass, R. & Raftery, A. Bayes factors. J. Am. Stat. Assoc. 90, 773–795 (2015).

    Article  MathSciNet  Google Scholar 

  28. Cordes, J. M. & Shannon, R. M. A measurement model for precision pulsar timing. Preprint at https://arxiv.org/abs/1010.3785 (2010).

  29. Dib, R., Kaspi, V. M. & Gavriil, F. P. Glitches in anomalous X-ray pulsars. Astrophys. J. 673, 1044–1061 (2008).

    Article  ADS  Google Scholar 

  30. Weltevrede, P., Johnston, S. & Espinoza, C. M. The glitch-induced identity changes of PSR J1119-6127. Mon. Not. R. Astron. Soc. 411, 1917–1934 (2011).

    Article  ADS  Google Scholar 

  31. Archibald, R. F., Kaspi, V. M., Tendulkar, S. P. & Scholz, P. A magnetar-like outburst from a high-B radio pulsar. Astrophys. J. 829, L21 (2016).

    Article  ADS  Google Scholar 

  32. Alpar, M. A., Anderson, P. W., Pines, D. & Shaham, J. Giant glitches and pinned vorticity in the Vela and other pulsars. Astrophys. J. 249, L29–L33 (1981).

    Article  ADS  Google Scholar 

  33. Link, B. K. & Epstein, R. I. Mechanics and energetics of vortex unpinning in neutron stars. Astrophys. J. 373, 592 (1991).

    Article  ADS  Google Scholar 

  34. Pizzochero, P. M. Angular momentum transfer in Vela-like pulsar glitches. Astrophys. J. 743, L20 (2011).

    Article  ADS  Google Scholar 

  35. Melatos, A., Peralta, C. & Wyithe, J. S. B. Avalanche dynamics of radio pulsar glitches. Astrophys. J. 672, 1103–1118 (2008).

    Article  ADS  Google Scholar 

  36. Fuentes, J. R. et al. The glitch activity of neutron stars. Astron. Astrophys. 608, A131 (2017).

    Article  Google Scholar 

  37. Howitt, G., Melatos, A. & Delaigle, A. Nonparametric estimation of the size and waiting time distributions of pulsar glitches. Astrophys. J. 867, 60 (2018).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

We are grateful to A. Melatos and I. Jones for valuable comments. Computations were performed on the OzStar supercomputer. P.D.L. is supported through an Australian Research Council Future Fellowship FT160100112 and Discovery Project DP180103155. V.G. is supported by a McGill Space Institute postdoctoral fellowship and the Trottier Chair in Astrophysics and Cosmology.

Author information

Authors and Affiliations

  1. School of Physics and Astronomy, Monash University, Melbourne, Victoria, Australia

    Gregory Ashton & Paul D. Lasky

  2. OzGrav: The ARC Centre of Excellence for Gravitational Wave Discovery, Clayton, Victoria, Australia

    Gregory Ashton & Paul D. Lasky

  3. Department of Physics and McGill Space Institute, McGill University, Montreal, Quebec, Canada

    Vanessa Graber

  4. School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia

    Jim Palfreyman

Authors
  1. Gregory Ashton
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Paul D. Lasky
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Vanessa Graber
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Jim Palfreyman
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

G.A. was responsible for the data analysis. G.A., P.D.L. and V.G. were responsible for the model development and discussion. J.P. was responsible for the data collection and reduction.

Corresponding author

Correspondence to Gregory Ashton.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ashton, G., Lasky, P.D., Graber, V. et al. Rotational evolution of the Vela pulsar during the 2016 glitch. Nat Astron 3, 1143–1148 (2019). https://doi.org/10.1038/s41550-019-0844-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41550-019-0844-6

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing