Abstract
NINE globular clusters are known to contain luminous (Lx> 1036 erg sā1) X-ray sources, but because the X-ray position error boxes, a few arcseconds in size, contain many stars, optical iden-tification of the sources has not been possible, with the exception of that in NGC7078 (ref. 19). This has prevented detailed investiga-tion of the emitting objects. If the X-ray sources are similar to low-mass X-ray binaries (LMXBs) outside globular clusters, low-level radio emission would be expected1,2, and the detection of such radio emission would both strengthen the case that luminous globular cluster X-ray sources are LMXBs and aid optical iden-tification by means of an accurate radio position. We report here the detection of radio emission from the position of the luminous X-ray source A1850ā08 (ref. 3) in the globular cluster NGC6712. The centroid of the slightly elongated radio source coincides with a previously suggested 20th magnitude stellar optical counterpart4. If the radio emission is synchrotron radiation, the minimum energy requirement and magnetic field strength are similar to what is found in the radio counterparts to other high-luminosity X-ray sources such as Sco X-l and Cyg X-3.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Hjellming, R. M. & Johnston, K. J. in The Physics of Accretion onto Compact Objects (eds Mason, K. O., Watson, M. G. & White, N. E.) (Springer, New York, 1986).
Grindlay, J. E. & Seaquist, E. R. Astrophys. J. 310, 172ā175 (1986).
Seward, F. D., Page, C. G., Turner, M. J. L. & Pounds, K. A. Mon. Not. R. astr. Soc. 175, 39Pā46P (1976).
Cudworth, K. M. Astr. J. 96, 105ā115 (1988).
Machin, G., Lehto, H. J., McHardy, I. M., Callanan, P. J. & Charles, P. A. Mon. Not. R. astr. Soc. (in the press).
Grindlay, J. E. et al. Astrophys. J. 212, L67āL71 (1977).
Doxey, R., Apparao, K. M. V., Brandt, H. V., Dower, R. G. & Jernigan, J. G. Nature 269, 112ā116 (1977).
Cominsky, L., Forman, W., Jones, C. & Tananbaum, H. Astrophys. J. 211, L9āL13 (1977).
Swank, J. H., Becker, R. H., Pravdo, S. H., Saba, J. R. & Serelemitsos, P. J. IAU Circ. No. 3010 (1976).
Jernigan, J. F. & Clark, G. W. Astrophys. J. 231, L125āL129 (1979).
Brandt, H. V., Doxsey, R. E. & Jernigan, J. G. in Proc. Symp. 21st Plenary Mtg of COSPAR (eds Baity, W. A. & Peterson, L. E.) 3ā66 (Pergamon, New York, 1978).
Grindlay, J. E., Hertz, P., Steiner, J. E., Murray, S. S. & Lightman, A. P. Astrophys. J. 282, L13āL16 (1984).
Bailyn, C. D., Grindlay, J. E., Cohn, H. & Lugger, P. M. Astrophys. J. 331, 303ā312 (1988).
Nieto, J. L. et al. IAU Circ. No. 4944 (1990).
Fomalont, E. B., Kellerman, K. I., Wall, J. V. & Weistrop D. Science 225, 23ā28 (1984).
Kallman, T. R. & McCray, R. Astrophys. J. Suppl. Ser. 50, 263ā318 (1982).
Pacholczyk, A. G. Radio Astrophysics (Freeman, San Francisco, 1970).
Strom, R. G., van Paradijis, J. & van der Klis, M. Nature 337, 234ā236 (1989).
AuriĆØre, M., Le FĆ©vre, O. & Terzan, A. Astr. Astrophys. 138, 415ā420 (1984).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lehto, H., Machin, G., McHardy, I. et al. The identity and position of X-ray sources in globular clusters: radio emission from NGC6712. Nature 347, 49ā51 (1990). https://doi.org/10.1038/347049a0
Issue Date:
DOI: https://doi.org/10.1038/347049a0
This article is cited by
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.
