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Nuclear-powered millisecond pulsars and the maximum spin frequency of neutron stars

Nature volume 424, pages 42–44 (2003)Cite this article

Abstract

Millisecond pulsars are neutron stars that are thought to have been spun-up by mass accretion from a stellar companion1. It is not known whether there is a natural brake for this process, or if it continues until the centrifugal breakup limit is reached at submillisecond periods. Many neutron stars that are accreting mass from a companion star exhibit thermonuclear X-ray bursts that last tens of seconds, caused by unstable nuclear burning on their surfaces2. Millisecond-period brightness oscillations during bursts from ten neutron stars (as distinct from other rapid X-ray variability that is also observed3,4) are thought to measure the stellar spin2,5, but direct proof of a rotational origin has been lacking. Here we report the detection of burst oscillations at the known spin frequency of an accreting millisecond pulsar, and we show that these oscillations always have the same rotational phase. This firmly establishes burst oscillations as nuclear-powered pulsations tracing the spin of accreting neutron stars, corroborating earlier evidence5,6. The distribution of spin frequencies of the 11 nuclear-powered pulsars cuts off well below the breakup frequency for most neutron-star models, supporting theoretical predictions that gravitational radiation losses can limit accretion torques in spinning up millisecond pulsars7,8,9.

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Figure 1: Dynamic power spectra of millisecond oscillations in an X-ray burst on 18 October 2002 from SAX J1808.4–3658.
Figure 2: Relative phase of the burst tail oscillations in SAX J1808.4–3658, and the persistent accretion-powered pulsations just before the burst, for all four bursts.

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References

  1. Alpar, M. A., Cheng, A. F., Ruderman, M. A. & Shaham, J. A new class of radio pulsars. Nature 300, 728–730 (1982)

    Article  ADS  Google Scholar 

  2. Strohmayer, T. E. & Bildsten, L. in Compact Stellar X-Ray Sources (eds Lewin, W. H. G. & van der Klis, M.) (Cambridge Univ. Press, in the press); preprint at 〈http://arXiv.org/astro-ph/0301544〉 2003

    Google Scholar 

  3. van der Klis, M. Millisecond oscillations in X-ray binaries. Annu. Rev. Astron. Astrophys. 38, 717–760 (2000)

    Article  ADS  Google Scholar 

  4. Wijnands, R. et al. Kilohertz quasi-periodic X-ray brightness fluctuations from an accreting millisecond pulsar. Nature (in the press)

  5. Strohmayer, T. E. et al. Millisecond variability from an accreting neutron star system. Astrophys. J. 469, L9–L12 (1996)

    Article  ADS  CAS  Google Scholar 

  6. Strohmayer, T. E. & Markwardt, C. B. Evidence for a millisecond pulsar in 4U 1636–53 during a superburst. Astrophys. J. 577, 337–345 (2002)

    Article  ADS  Google Scholar 

  7. Wagoner, R. V. Gravitational radiation from accreting neutron stars. Astrophys. J. 278, 345–348 (1984)

    Article  ADS  Google Scholar 

  8. Bildsten, L. Gravitational radiation and rotating neutron stars. Astrophys. J. 501, L89–L93 (1998)

    Article  ADS  Google Scholar 

  9. Andersson, N., Kokkotas, K. D. & Stergioulas, N. On the relevance of the r-mode instability for accreting neutron stars and white dwarfs. Astrophys. J. 516, 307–314 (1999)

    Article  ADS  Google Scholar 

  10. Strohmayer, T. E., Jahoda, K., Giles, A. B. & Lee, U. Millisecond pulsations from a low-mass X-ray binary system in the Galactic center region. Astrophys. J. 486, 355–362 (1997)

    Article  ADS  Google Scholar 

  11. Cumming, A. & Bildsten, L. Rotational evolution during type I X-ray bursts. Astrophys. J. 544, 453–474 (2000)

    Article  ADS  CAS  Google Scholar 

  12. in't Zand, J. J. et al. Discovery of the X-ray transient SAX J1808.4–3658, a likely low-mass X-ray binary. Astron. Astrophys. 331, L25–L28 (1998)

    ADS  Google Scholar 

  13. Wijnands, R. & van der Klis, M. A millisecond pulsar in an X-ray binary system. Nature 394, 344–346 (1998)

    Article  ADS  CAS  Google Scholar 

  14. Chakrabarty, D. & Morgan, E. H. The two-hour orbit of a binary millisecond X-ray pulsar. Nature 394, 346–348 (1998)

    Article  ADS  CAS  Google Scholar 

  15. in't Zand, J. J. et al. The first outburst of SAX J1808.4–3658 revisited. Astron. Astrophys. 372, 916–921 (2001)

    Article  ADS  Google Scholar 

  16. Muno, M. P., Chakrabarty, D., Galloway, D. K. & Psaltis, D. The frequency stability of millisecond oscillations in thermonuclear X-ray bursts. Astrophys. J. 580, 1048–1059 (2002)

    Article  ADS  Google Scholar 

  17. Wijnands, R., Strohmayer, T. & Franco, L. M. Discovery of nearly coherent oscillations with a frequency of 567 Hz during type I X-ray bursts of the X-ray transient and eclipsing binary X1658–298. Astrophys. J. 549, L71–L75 (2001)

    Article  ADS  Google Scholar 

  18. Galloway, D. K., Chakrabarty, D., Muno, M. P. & Savov, P. Discovery of a 270 hertz X-ray burst oscillation in the X-ray dipper 4U 1916–053. Astrophys. J. 549, L85–L88 (2001)

    Article  ADS  Google Scholar 

  19. Markwardt, C. B., Swank, J. H., Strohmayer, T. E., in't Zand, J. J. M. & Marshall, F. E. Discovery of a second millisecond accreting pulsar: XTE J1751–305. Astrophys. J. 575, L21–L24 (2002)

    Article  ADS  Google Scholar 

  20. Galloway, D. K., Chakrabarty, D., Morgan, E. H. & Remillard, R. A. Discovery of a high-latitude accreting millisecond pulsar in an ultracompact binary. Astrophys. J. 576, L137–L140 (2002)

    Article  ADS  Google Scholar 

  21. Markwardt, C. B., Smith, E. & Swank, J. H. XTE J1807–294. IAU Circ. No. 8080 (2003).

  22. Cumming, A., Zweibel, E. & Bildstenm, L. Magnetic screening in accreting neutron stars. Astrophys. J. 557, 958–966 (2001)

    Article  ADS  Google Scholar 

  23. Spitkovsky, A., Levin, Y. & Ushomirsky, G. Propagation of thermonuclear flames on rapidly rotating neutron stars: Extreme weather during type I X-ray bursts. Astrophys. J. 566, 1018–1038 (2002)

    Article  ADS  Google Scholar 

  24. Cook, G. B., Shapiro, S. L. & Teukolsky, S. A. Recycling pulsars to millisecond periods in general relativity. Astrophys. J. 421, L117–L120 (1994)

    Article  ADS  Google Scholar 

  25. Haensel, P., Lasota, J. P. & Zdunik, J. L. On the minimum period of uniformly rotating neutron stars. Astron. Astrophys. 344, 151–153 (1999)

    ADS  Google Scholar 

  26. Backer, D. C., Kulkarni, S. R., Heiles, C. E., Davis, M. M. & Goss, W. M. A millisecond pulsar. Nature 300, 615–618 (1982)

    Article  ADS  Google Scholar 

  27. Cook, G. B., Shapiro, S. L. & Teukolsky, S. A. Rapidly rotating neutron stars in general relativity: Realistic equations of state. Astrophys. J. 424, 823–845 (1994)

    Article  ADS  Google Scholar 

  28. Psaltis, D. & Chakrabarty, D. The disk-magnetosphere interaction in the accretion-powered millisecond pulsar SAX J1808.4–3658. Astrophys. J. 521, 332–340 (1999)

    Article  ADS  Google Scholar 

  29. Camilo, F., Thorsett, S. E. & Kulkarni, S. R. The magnetic fields, ages, and original spin periods of millisecond pulsars. Astrophys. J. 421, L15–L18 (1994)

    Article  ADS  Google Scholar 

  30. Bildsten, L. in Radio Pulsars (eds Bailes, M., Nice, D. J. & Thorsett, S. E.) (Astronomical Society of the Pacific, San Francisco, in the press); preprint at 〈http://arXiv.org/astro-ph/0212004〉 (2002).

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Acknowledgements

We thank L. Bildsten, F. Lamb, D. Psaltis and S. Thorsett for discussions. This work was supported in part by NASA and the Alfred P. Sloan Foundation.

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Authors and Affiliations

  1. Department of Physics and Center for Space Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, USA

    Deepto Chakrabarty, Edward H. Morgan, Michael P. Muno & Duncan K. Galloway

  2. Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California, 93106, USA

    Deepto Chakrabarty

  3. School of Physics and Astronomy, University of St Andrews, North Haugh, Fife, KY16 9SS, St Andrews, UK

    Rudy Wijnands

  4. Astronomical Institute “Anton Pannekoek” and Center for High-Energy Astrophysics, University of Amsterdam, Kruislaan 403, 1098 SJ, Amsterdam, The Netherlands

    Michiel van der Klis

  5. Department of Astronomy, University of Maryland, College Park, Maryland, 20742, USA

    Craig B. Markwardt

  6. Laboratory for High Energy Astrophysics, NASA Goddard Space Flight Center, Greenbelt, Maryland, 20771, USA

    Craig B. Markwardt

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  1. Deepto Chakrabarty
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Correspondence to Deepto Chakrabarty.

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Chakrabarty, D., Morgan, E., Muno, M. et al. Nuclear-powered millisecond pulsars and the maximum spin frequency of neutron stars. Nature 424, 42–44 (2003). https://doi.org/10.1038/nature01732

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