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:

Variability of the BL Lacertae object AO0235+164

Abstract

WE can summarise previous1–3 discussion of the problem of excessive Compton scattering in variable compact non-thermal sources by saying that the small size implied by rapid variability leads to too large a probability that a given electron will Compton-scatter one of the emitted photons, leading to an excessive X-ray flux. The basic assumptions underlying these difficulties are that the time-variable radiation is produced by the incoherent synchrotron process by electrons with large pitch angles in randomly oriented magnetic fields, and that the objects are at the cosmological distances implied by their redshifts. We present here a crude model of the recently observed outburst4 of AO0235+164 in the near infrared and visible, where variability of up to 30% on time scales of 1 or 2 d has been noted. In our model the assumptions of large pitch angle and randomly oriented fields are relaxed5 and the model accords with our previous discussion3 of the low-frequency variability of the radio sources 3C454.3 and CTA 102.

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

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

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

Similar content being viewed by others

References

  1. Burbidge, G. R. & Stein, W. A. Comments Astrophys. Space Phys. 6, 87 (1975).

    ADS  Google Scholar 

  2. Jones, T. W. & Burbidge, G. R. Astrophys. J. 186, 791 (1973).

    Article  ADS  Google Scholar 

  3. Cocke, W. J. & Pacholczyk, A. G. Astrophys. J. 195, 279 (1975).

    Article  ADS  Google Scholar 

  4. Rieke, G. H., Grasdalen, G. L., Kinman, T. D., Hintzen, P., Wills, B. J. & Wills, D., Nature, 260, 754 (1976).

    Article  ADS  CAS  Google Scholar 

  5. Woltjer, L. Astrophys. J. 146, 597 (1966).

    Article  ADS  Google Scholar 

  6. Morrison, P. Astrophys. J. Lett. 157, L73 (1969).

    Article  ADS  Google Scholar 

  7. Epstein, R. I. Astrophys. J. 183, 593 (1973).

    Article  ADS  Google Scholar 

  8. Sanders, R. H. Nature 248, 390 (1974).

    Article  ADS  Google Scholar 

  9. Wittels, J. J. et al. Astrophys. J. Lett. 206, L75

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

COCKE, W., PACHOLCZYK, A. Variability of the BL Lacertae object AO0235+164. Nature 265, 608–609 (1977). https://doi.org/10.1038/265608a0

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/265608a0

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.

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