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The Sources of Major Heliospheric Disturbances

Published online by Cambridge University Press:  30 March 2016

A. Hewish
A. Hewish*
Affiliation:
Cavendish Laboratory, Madingley Road, Cambridge, CB3 OHE

Abstract

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Observations of interplanetary scintillation on about 900 sources made with the 3.6 hectare array at Cambridge have been used to map, and to track, 96 heliospheric transients during August 1978–September 1979. This sample included most of the interplanetary shocks recorded by near-Earth spacecraft in the same period.

Some corotating interaction regions were observed but the most frequent disturbances were “erupting streams” in which spherical shells of enhanced density were driven by the birth of high-speed solar wind streams which persisted for several days. Although these transients were of the type traditionally associated with solar flares or disappearing filaments they were not caused by such processes. Back-projection to the Sun indicated that the sources were always associated with coronal holes. It is concluded that the sources of the most energetic interplanetary transients are mid-latitude coronal holes which, near solar maximum, produce sporadic high-speed streams lasting several days, in contrast to the more stable flows typical of the declining phase of the solar cycle.

Type
Joint Commission Meetings
Information
Highlights of Astronomy , Volume 7: Highlights of Astronomy. As presented at the XIXth General Assembly of the IAU, 1985 , 1986 , pp. 749 - 753
Copyright
Copyright © Reidel 1986

References

Gapper, G.R., Hewish, A. Purvis, A. and Duffett-Smith, P.J.: Nature. 296, 633, 1982.Google Scholar
Hewish, A., Tappin, S.J. and Gapper, G.R.: Nature. 314, 137, 1985.Google Scholar
Sheeley, N.R. Jr, Howard, R.A., Koomen, M.J., Schwenn, R., Mulhauser, K.H. and Rosenbauer, H.: J. Geophys. Res. 90, 163, 1984.Google Scholar
Tappin, S.J., Hewish, A. and Gapper, G.R.: Planet. Space Sci. 31, 1171, 1983.Google Scholar
Tappin, S.J., Hewish, A. and Gapper, G.R.: Planet. Space Sci. 32, 1273, 1984 CrossRefGoogle Scholar
Tappin, S.J.: Planet. Space Sci. (in press).Google Scholar
Wagner, W.J.: Ann. Rev. Astron. Astrophys. 22, 267, 1984.Google Scholar