Abstract
CYGNUS X-3 is a candidate for the radio source which in September 1972 experienced a series of exceptional radio outbursts1. The X-ray emission is chiefly distinguishable as showing periodic intensity variations with a period of 4.8 h (ref. 2); if these variations are caused by an eclipse, the orbital period is the shortest observed up to this time from an X-ray source. The definite identification of the radio source with the X-ray source has remained unconfirmed up to now because of the poor positional accuracy of the X-ray source; the error box in the 3U catalogue is about 1 x 2 arc min (ref. 3). Although there is no visual candidate for Cyg X-3 to a limit of ∼2 X 10−32 W m−2 Hz−1 (V∼23 mag) (ref. 4), at infrared wavelengths Becklin et al.5 found a source coincident to ±2 arc s with the radio position. At 2.2 μm, the flux density is approximately 2 X 10−28 W m−2 Hz−1, whereas the 1.5 to 2.2 µm colour of the infrared source is consistent with a Rayleigh-Jeans spectrum which is reddened by 1.5 mag at 2.2 µm by the interstellar medium. There is no reason to suppose that the source is intrinsically more luminous in the infrared than at visible wavelengths.
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
Gregory, P. C., Kronberg, P. P., Seaquist, E. R., Hughes, V. A., Woodsworth, A., Viner, M. R., and Retallack, D., Nature phys. Sci., 239, 440 (1972).
Canizares, C. R., McClintock, J. E., Clark, G. W., Lewin, W. H. G., Schnopper, H. W., and Sprott, G. F., Nature phys. Sci., 241, 28 (1973).
Giacconi, R., Murray, S., Gursky, H., Kellogg, E., Schreier, E., Matilsky, T., Koch, D., and Tananbaum, H., Astrophys. J. (in the press).
Westphal, J. A., Kristian, J., Huchra, J. P., Shectman, S. A., and Brucato, R. J., Nature phys. Sci., 239, 134 (1972).
Becklin, E. E., Kristian, J., Neugebauer, G., and Wynn-Williams, C. G., Nature phys. Sci., 239, 130 (1972).
Becklin, E. E., and Neugebauer, G., Astrophys. J., 151, 145 (1968).
Branson, N. J. B. A., Martin, A. H. M., Pooley, G. G., Readhead, A. C. S., Shakeshaft, J. R., Slingo, A., and Warner, P. J., Nature phys. Sci., 239, 133 (1972).
Hawkins, F. J., Mason, K. O., and Sanford, P. W., Nature phys. Sci., 241, 109 (1973).
Braes, L. L. E., Miley, G. K., Shane, W. W., Baars, J. W. M., and GOSS, W. M., Nature phys. Sci., 242, 66 (1973).
Neugebauer, G., Oke, J. B., Becklin, E. E., and Garmire, G., Astrophys. J., 155, 1 (1969).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
BECKLIN, E., NEUGEBAUER, G., HAWKINS, F. et al. Infrared and X-ray Variability of Cyg X-3. Nature 245, 302–304 (1973). https://doi.org/10.1038/245302a0
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1038/245302a0
This article is cited by
-
Infrared helium emission lines from Cygnus X-3 suggesting a Wolf-Rayet star companion
Nature (1992)
-
Search for 12.6 millisecond periodicity in TeV gamma rays from Cygnus X-3
Journal of Astrophysics and Astronomy (1988)
-
Free precession of Cyg X-3 and the 34.1-day periodicity
Astrophysics and Space Science (1985)
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.