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.

Transient pulsed radio emission from a magnetar

Abstract

Anomalous X-ray pulsars (AXPs) are slowly rotating neutron stars with very bright and highly variable X-ray emission that are believed to be powered by ultra-strong magnetic fields of >1014 G, according to the ‘magnetar’ model1. The radio pulsations that have been observed from more than 1,700 neutron stars with weaker magnetic fields have never been detected from any of the dozen known magnetars. The X-ray pulsar XTE J1810 - 197 was revealed (in 2003) as the first AXP with transient emission when its luminosity increased 100-fold from the quiescent level2; a coincident radio source of unknown origin was detected one year later3. Here we show that XTE J1810 - 197 emits bright, narrow, highly linearly polarized radio pulses, observed at every rotation, thereby establishing that magnetars can be radio pulsars. There is no evidence of radio emission before the 2003 X-ray outburst (unlike ordinary pulsars, which emit radio pulses all the time), and the flux varies from day to day. The flux at all radio frequencies is approximately equal—and at >20 GHz XTE J1810 - 197 is currently the brightest neutron star known. These observations link magnetars to ordinary radio pulsars, rule out alternative accretion models for AXPs, and provide a new window into the coronae of magnetars.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

  • Fast radio bursts

    The Astronomy and Astrophysics Review Open Access 24 May 2019

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Average radio pulse profiles of XTE J1810 - 197 at frequencies 0.7–42 GHz.
Figure 2: Single pulses from XTE J1810 - 197 at frequencies of 2 and 42 GHz.

References

  1. Duncan, R. C. & Thompson, C. Formation of very strongly magnetized neutron stars: implications for gamma-ray bursts. Astrophys. J. 392, L9–L13 (1992)

    ADS  CAS  Article  Google Scholar 

  2. Ibrahim, A. I. et al. Discovery of a transient magnetar: XTE J1810 - 197. Astrophys. J. 609, L21–L24 (2004)

    ADS  CAS  Article  Google Scholar 

  3. Halpern, J. P., Gotthelf, E. V., Becker, R. H., Helfand, D. J. & White, R. L. Discovery of radio emission from the transient anomalous X-ray pulsar XTE J1810 - 197. Astrophys. J. 632, L29–L32 (2005)

    ADS  CAS  Article  Google Scholar 

  4. Israel, G. L. et al. Accurate X-ray position of the anomalous X-ray pulsar XTE J1810 - 197 and identification of its likely infrared counterpart. Astrophys. J. 603, L97–L100 (2004)

    ADS  Article  Google Scholar 

  5. Manchester, R. N. et al. The Parkes multi-beam pulsar survey—I. Observing and data analysis systems, discovery and timing of 100 pulsars. Mon. Not. R. Astron. Soc. 328, 17–35 (2001)

    ADS  Article  Google Scholar 

  6. Cordes, J. M., Bhat, N. D. R., Hankins, T. H., McLaughlin, M. A. & Kern, J. The brightest pulses in the Universe: multifrequency observations of the Crab pulsar's giant pulses. Astrophys. J. 612, 375–388 (2004)

    ADS  Article  Google Scholar 

  7. Cordes, J. M. & Lazio, T. J. W. NE2001. I. A new model for the Galactic distribution of free electrons and its fluctuations. Preprint at http://arxiv.org/astro-ph/0207156 (2002).

  8. Gotthelf, E. V. & Halpern, J. P. The spectral evolution of transient anomalous X-ray pulsar XTE J1810 - 197. Astrophys. J. 632, 1075–1085 (2005)

    ADS  CAS  Article  Google Scholar 

  9. Gotthelf, E. V., Halpern, J. P., Buxton, M. & Bailyn, C. Imaging X-ray, optical, and infrared observations of the transient anomalous X-ray pulsar XTE J1810 - 197. Astrophys. J. 605, 368–377 (2004)

    ADS  CAS  Article  Google Scholar 

  10. Durant, M. & van Kerkwijk, M. H. Distances to anomalous X-ray pulsars using red clump stars. Astrophys. J. (in the press); preprint at http://arxiv.org/astro-ph/0606027 (2006).

  11. Rickett, B. J. Radio propagation through the turbulent interstellar plasma. Annu. Rev. Astron. Astrophys. 28, 561–605 (1990)

    ADS  Article  Google Scholar 

  12. Narayan, R. The physics of pulsar scintillation. Phil. Trans. R. Soc. A 341, 151–165 (1992)

    ADS  Google Scholar 

  13. Lorimer, D. R., Yates, J. A., Lyne, A. G. & Gould, D. M. Multifrequency flux density measurements of 280 pulsars. Mon. Not. R. Astron. Soc. 273, 411–421 (1995)

    ADS  Article  Google Scholar 

  14. Kaspi, V. M. & McLaughlin, M. A. Chandra X-ray detection of the high-magnetic-field radio pulsar PSR J1718–3718. Astrophys. J. 618, L41–L44 (2005)

    ADS  CAS  Article  Google Scholar 

  15. McLaughlin, M. A. et al. Transient radio bursts from rotating neutron stars. Nature 439, 817–820 (2006)

    ADS  CAS  Article  Google Scholar 

  16. Reynolds, S. P. et al. Discovery of the X-ray counterpart to the rotating radio transient J1819–1458. Astrophys. J. 639, L71–L74 (2006)

    ADS  CAS  Article  Google Scholar 

  17. Thompson, C. & Beloborodov, A. M. High-energy emission from magnetars. Astrophys. J. 634, 565–569 (2005)

    ADS  CAS  Article  Google Scholar 

  18. Beloborodov, A. M. & Thompson, C. Corona of magnetars. Astrophys. J. (submitted); preprint at http://arxiv.org/astro-ph/0602417 (2006).

  19. Zhang, B. On the radio quiescence of anomalous X-ray pulsars and soft gamma-ray repeaters. Astrophys. J. 562, L59–L62 (2001)

    ADS  Article  Google Scholar 

  20. Thompson, C., Lyutikov, M. & Kulkarni, S. R. Electrodynamics of magnetars: implications for the persistent X-ray emission and spin-down of the soft gamma repeaters and anomalous X-ray pulsars. Astrophys. J. 574, 332–355 (2002)

    ADS  Article  Google Scholar 

  21. Goldreich, P. & Julian, W. H. Pulsar electrodynamics. Astrophys. J. 157, 869–880 (1969)

    ADS  Article  Google Scholar 

  22. Eichler, D., Gedalin, M. & Lyubarsky, Y. Coherent emission from magnetars. Astrophys. J. 578, L121–L124 (2002)

    ADS  Article  Google Scholar 

  23. Eichler, D., Lyubarsky, Y., Thompson, C. & Woods, P. M. In Pulsars, AXPs and SGRs Observed with BeppoSAX and Other Observatories (eds Cusumano, G., Massaro, E. & Mineo, T.) 215–222 (Aracne Editrice, Rome, 2003)

    Google Scholar 

  24. Lyutikov, M. Radio emission from magnetars. Astrophys. J. 580, L65–L68 (2002)

    ADS  Article  Google Scholar 

  25. Rea, N. et al. Correlated infrared and X-ray variability of the transient anomalous X-ray pulsar XTE J1810 - 197. Astron. Astrophys. 425, L5–L8 (2004)

    ADS  Article  Google Scholar 

  26. Halpern, J. P. & Gotthelf, E. V. The fading of transient anomalous X-ray pulsar XTE J1810 - 197. Astrophys. J. 618, 874–882 (2005)

    ADS  CAS  Article  Google Scholar 

  27. Backer, D. C. Peculiar pulse burst in PSR 1237 + 25. Nature 228, 1297–1298 (1970)

    ADS  Article  Google Scholar 

  28. Backer, D. C. et al. A digital signal processor for pulsar research. Publ. Astron. Soc. Pacif. 109, 61–68 (1997)

    ADS  Article  Google Scholar 

  29. Kaplan, D. L. et al. The Green Bank Telescope pulsar Spigot. Publ. Astron. Soc. Pacif. 117, 643–653 (2005)

    ADS  Article  Google Scholar 

  30. Drake, F. D. & Craft, H. D. Second periodic pulsations in pulsars. Nature 220, 231–235 (1968)

    ADS  Article  Google Scholar 

Download references

Acknowledgements

We thank J. Cohen and B. Mason for giving us some of their observing time, M. Kramer and M. McLaughlin for providing us with Parkes multibeam survey archival data, and D. Backer, D. Kaplan, and B. Jacoby for their contributions to developing pulsar observing equipment at GBT. The Parkes Observatory is part of the Australia Telescope, which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. The National Radio Astronomy Observatory is a facility of the US National Science Foundation (NSF), operated under cooperative agreement by Associated Universities, Inc. F.C. acknowledges support from NSF and NASA.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Fernando Camilo.

Ethics declarations

Competing interests

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Camilo, F., Ransom, S., Halpern, J. et al. Transient pulsed radio emission from a magnetar. Nature 442, 892–895 (2006). https://doi.org/10.1038/nature04986

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature04986

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

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