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.

  • Letter
  • Published:

Ejection of pulsars and binaries to the outskirts of globular clusters

Abstract

THREE-BODY interactions can eject stars, singly or in binaries, from the core of a globular cluster to its outskirts, whither dynamical friction may take more than 108 yr to return them. We show here that such a process can explain why the binary pulsar 2127 + 11C in the cluster Ml5 (and perhaps 1744–24A in Terzan 5) is now far from the cluster core. A suitable encounter could have given the pulsar enough velocity to eject it to its present position, and also replaced its original stellar companion with a neutron star. For ejection of PSR2127 +11C to be likely, the core of M15 must be composed of heavy degenerate stars at a density greater than 107pc-3, maintained for 108yr; this is consistent with previous dynamical estimates. A natural combination of factors enables us to see 2127 + 11C: a binary of longer period could not have received a large enough impulse to escape the core, whereas one of shorter period would have been ejected from the cluster or would have collapsed because of orbital decay by gravitational radiation. Pulsars and pulsar binaries ejected from clusters will contribute to the birth rate of recycled pulsars in the inner Galaxy.

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

Access options

Buy this article

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

Similar content being viewed by others

References

  1. Charles, P. A. in Proc. 23rd ESLAB Symp., Topics in X-ray Astronomy, ESA SP-296 Vol. 1 (ed. White, N.), 129–137 (European Space Agency, Paris, 1989).

    Google Scholar 

  2. IIovaisky, S. A. in Proc. 23rd ESLAB Symp., Topics in X-ray Astronomy, ESA SP-296 Vol. 1 (ed. White, N.) 145–150 (European Space Agency, Paris, 1989).

    Google Scholar 

  3. Anderson, S. B., Gorham, P. W., Kulkarni, S. R., Prince, T. A. & Wolszczan, A. Nature 346, 42–44 (1990).

    Article  ADS  Google Scholar 

  4. Lugger, P. M., Conn, H., Grindlay, J. E., Bailyn, C. D. & Hertz, P. Astrophys. J. 320, 482–492 (1987).

    Article  ADS  Google Scholar 

  5. Anderson, S. B., Kulkarni, S. R., Prince, T. A. & Wolszczan, A. Nature (submitted).

  6. Seitzer, P., Peterson, R. & Cudworth, K. in Dynamics of Dense Stellar Systems (ed. Merritt, D.) 153–156 (Cambridge University Press, 1989).

    Google Scholar 

  7. Peterson, R. C., Seitzer, P. & Cudworth, K. M. Astrophys. J. 347, 251–265 (1989).

    Article  ADS  Google Scholar 

  8. Phinney, E. S. Mon. Not. R. astr. Soc. (in the press).

  9. McMillan, S. L. W. Astrophys. J. 306, 552–564 (1986).

    Article  ADS  Google Scholar 

  10. Hut, P. & Inagaki, S. Astrophys. J. 298, 502–520 (1985).

    Article  ADS  Google Scholar 

  11. Murphy, B. W., Cohn, H. N. & Hut, P. Mon. Not. R. astr. Soc. 245, 335–349 (1990).

    ADS  Google Scholar 

  12. Chernoff, D. F. & Djorgovski, S. Astrophys. J. 339, 904–918 (1989).

    Article  ADS  Google Scholar 

  13. Kulkarni, S. R., Narayan, R. & Romani, R. W. Astrophys. J. 356, 174–183 (1990).

    Article  ADS  CAS  Google Scholar 

  14. Taylor, J. H. & Weisberg, J. M. Astrophys. J. 345, 434–450 (1989).

    Article  ADS  Google Scholar 

  15. Burrows, A. & Woosley, S. Astrophys. J. 308, 680–684 (1986).

    Article  ADS  Google Scholar 

  16. King, I. R. Astr. J. 71, 64–75 (1966).

    Article  ADS  Google Scholar 

  17. Shara, M. M., Moffatt, A. F. J. & Potter, M. Astr. J. 99, 1858–1862 (1990).

    Article  ADS  CAS  Google Scholar 

  18. Lauer, T. R. et al. Astrophys. J. (in the press).

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Phinney, E., Sigurdsson, S. Ejection of pulsars and binaries to the outskirts of globular clusters. Nature 349, 220–223 (1991). https://doi.org/10.1038/349220a0

Download citation

  • Received:

  • Accepted:

  • Issue date:

  • DOI: https://doi.org/10.1038/349220a0

This article is cited by

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