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.

  • Letters to Editor
  • Published:

Hard X-ray Spectrum of Hercules X-1

Nature Physical Science volume 244, pages 59–60 (1973)Cite this article

Abstract

SPECTRAL results on the periodic pulsating binary X-ray source Hercules X-1 are still very meagre. The only results available are from satellite instruments and for energies below 40 keV. The Uhuru results (R. Giacconi et al., unpublished) show that the intensity and the spectral characteristics vary from day to day. The intensity is maximum during the central portion of the cycle and drops by a factor of about 2.7 towards the ends. The spectrum is flat during this period with a cutoff energy ˜1.5keV.

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

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

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

References

  1. Ulmer, M. P., Baity, W. A., Wheaton, W. A., and Peterson, L. E., Astrophys. J. Lett., 178, L61 (1972).

    Article  ADS  Google Scholar 

  2. Clark, G. W., Bradt, H. V., Lewin, W. H. G., Markert, T. H., Schnopper, H. W., and Sprott, G. F., Astrophys. J. Lett., 177, L109 (1972).

    Article  ADS  Google Scholar 

  3. Agrawal, P. C., Iyengar, V. S., Kalgaonkar, M. A., Kamat, A. P., Kunte, P. K., Manchanda, R. K., and Srinivasan, K. V., Nucl. Instrum. Meth., 95, 29 (1971).

    Article  ADS  Google Scholar 

  4. Agrawal, P. C., Biswas, S., Gokhale, G. S., Iyengar, V. S., Kunte, P. K., Manchanda, R. K., and Sreekantan, B. V., Non-Solar X-ray and Gamma-ray Astronomy (edit, by Gratton, L.), 94, 103 (Reider, 1970).

    Google Scholar 

  5. Giacconi, R., Murray, S., Gursky, H., Kellogg, E., Schreier, E., and Tananbaum, H., Astrophys. J. Lett., 178, 281 (1972).

    Article  ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Tata Institute of Fundamental Research, Bombay, 5

    R. K. MANCHANDA, V. S. IYENGAR, N. DURGAPRASAD, G. S. GOKHALE, P. K. KUNTE & B. V. SREEKANTAN

Authors
  1. R. K. MANCHANDA
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. V. S. IYENGAR
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. N. DURGAPRASAD
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. G. S. GOKHALE
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. P. K. KUNTE
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. B. V. SREEKANTAN
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

MANCHANDA, R., IYENGAR, V., DURGAPRASAD, N. et al. Hard X-ray Spectrum of Hercules X-1. Nature Physical Science 244, 59–60 (1973). https://doi.org/10.1038/physci244059a0

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1038/physci244059a0

This article is cited by

Search

Advanced 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