Abstract
A UNIQUELY intense pulsation of auroral-associated X rays, followed a solar cosmic flare in September 1966 and was detected by scintillation counters on a balloon platform at an altitude of about 32 km (ref. 1). The X rays were strongly modulated with a period of 4–6 s. Figures 1 and 2 show a portion of the amplitude-modulated intensity, the ratio of intensities in two neighbouring energy channels, the power spectrum for the X-ray intensity ratio, and the spectrum of intensity variations in the lower energy channel. It can be seen that the X-ray spectrum hardens as the pulsations grow and then softens with the subsequent decay, and that there are two peaks in the X-ray power spectrum.
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
Brown, R. R., and Weir, R. A. J., geophys, Res., 72, 5531–5536 (1967); J. atmos. terr. Phys., 29, 1611–1618 (1967).
Pfeffer, R. L. and Zarichny, J., Geofis. pura appl., 55, 175–199 (1963).
Tolstoy, I., J. acoust. Soc. Am., 28, 1182–1192 (1956).
Beta- and gamma-ray spectroscopy, (edit. by Siegbahn, K.), (Interscience, New York, 1955).
Procunier, R. W., Geophys. J. R. astr. Soc., 26, 183–189 (1971).
ESSA Technical Report WB 9, (US Dept Commerce, January 1969).
Baker, D. M., and Davies, K., J. geophys. Res., 73, 448–451 (1968).
Dobson, G. M. B., Proc. phys. Soc. Lon., 43, 324 (1931).
Hering, W. S., and Morden, R., Jr., US Air Force Cambridge Research Papers, No. 162, (1965).
Bojkov, R. D. J., Geophys., 72, 5585–5593 (1967).
Mitra, D. K., The upper atmosphere, second ed. (The Asiatic Society, Calcutta, ).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
WICKERSHAM, A. Sound wave modulation of auroral X rays. Nature 249, 538–540 (1974). https://doi.org/10.1038/249538a0
Received:
Issue Date:
DOI: https://doi.org/10.1038/249538a0
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.
