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Title: Information content of ionspheric solar flare effect observations. I. Experimental evidence of solar and atomospheric control of the flare effects

Abstract

On the basis of different SID-observations in certral Europe in the years 1969 and 1970, with special emphasis on the extremely strong flare period in June 1970, the combination of satellite x-ray observations with ionospheric observations and the problem of the respective efflciencies'' of the different kinds of ionospheric SID recordings (SFA, SEA, SSWF, and SCNA) have been investigated. It could be concluded, that the response of the lower ionosphere to solar flare x rays depends strongly on season and solar zenith angle X. Therefore a general estimation of x-ray fluxes from SID records (especially from their importances'' alone) can be very doubtful and seems possible only for strongly limited cases. The principally most efflcient method for monitoring and investigating solar flare effects in the lower ionosphere seems to be the LF field-strength observation (SFA) interpreted by quasiphase heights, Gross calculations of the scale heights between 69 and 78 km, on the basis of SFA- observations, are in general accordance with the Mean CIRA 1965-model. An upper limit for the electron production by x-ray flares in summer has been estimated. The ionospheric flare layer is 2 to 3 times thicker in winter than in summer. Also the time delay betweenmore » x-ray flare maximum and SFA-maximum is slightiy but signiflcantly shorter in winter than in summer, indicating that the mesosphere reacts faster and more sensitively in winter. Comparisons between SFA and SSWF indicate sensitive heights'' above about 80 km for SSWF and below 80 km for SFA. The time-sequence of the effects in different heights, during the initial phase, can be characterized in terms of a gradually down-coming SID layer. (auth)« less

Authors:
; ; ;
Publication Date:
Research Org.:
Deutsche Akademie der Wissenschaften, Berlin
OSTI Identifier:
4360739
NSA Number:
NSA-29-019254
Resource Type:
Journal Article
Journal Name:
J. Atmos. Terrest. Phys., v. 36, no. 3, pp. 513-524
Additional Journal Information:
Other Information: Orig. Receipt Date: 30-JUN-74; Bib. Info. Source: UK (United Kingdom (sent to DOE from))
Country of Publication:
United Kingdom
Language:
English
Subject:
N56400* -Physics (Astrophysics & Cosmology)-Solar Phenomena; N58100 -Physics (Atmospheric)-Auroral & Ionospheric Phenomena; *IONOSPHERE- SEASONAL VARIATIONS; *SOLAR FLARES- SUDDEN IONOSPHERIC DISTURBANCE; *SOLAR X-RAY BURSTS- SUDDEN IONOSPHERIC DISTURBANCE; ANGULAR DISTRIBUTION; ELECTRIC FIELDS; KHZ RANGE 100-1000; LEVELS; RADIOWAVE RADIATION; WAVE PROPAGATION; X RADIATION

Citation Formats

Ohle, K H, Knuth, R, Entzian, G, and Taubenheim, J. Information content of ionspheric solar flare effect observations. I. Experimental evidence of solar and atomospheric control of the flare effects. United Kingdom: N. p., 1974. Web. doi:10.1016/0021-9169(74)90130-5.
Ohle, K H, Knuth, R, Entzian, G, & Taubenheim, J. Information content of ionspheric solar flare effect observations. I. Experimental evidence of solar and atomospheric control of the flare effects. United Kingdom. https://doi.org/10.1016/0021-9169(74)90130-5
Ohle, K H, Knuth, R, Entzian, G, and Taubenheim, J. Fri . "Information content of ionspheric solar flare effect observations. I. Experimental evidence of solar and atomospheric control of the flare effects". United Kingdom. https://doi.org/10.1016/0021-9169(74)90130-5.
@article{osti_4360739,
title = {Information content of ionspheric solar flare effect observations. I. Experimental evidence of solar and atomospheric control of the flare effects},
author = {Ohle, K H and Knuth, R and Entzian, G and Taubenheim, J},
abstractNote = {On the basis of different SID-observations in certral Europe in the years 1969 and 1970, with special emphasis on the extremely strong flare period in June 1970, the combination of satellite x-ray observations with ionospheric observations and the problem of the respective efflciencies'' of the different kinds of ionospheric SID recordings (SFA, SEA, SSWF, and SCNA) have been investigated. It could be concluded, that the response of the lower ionosphere to solar flare x rays depends strongly on season and solar zenith angle X. Therefore a general estimation of x-ray fluxes from SID records (especially from their importances'' alone) can be very doubtful and seems possible only for strongly limited cases. The principally most efflcient method for monitoring and investigating solar flare effects in the lower ionosphere seems to be the LF field-strength observation (SFA) interpreted by quasiphase heights, Gross calculations of the scale heights between 69 and 78 km, on the basis of SFA- observations, are in general accordance with the Mean CIRA 1965-model. An upper limit for the electron production by x-ray flares in summer has been estimated. The ionospheric flare layer is 2 to 3 times thicker in winter than in summer. Also the time delay between x-ray flare maximum and SFA-maximum is slightiy but signiflcantly shorter in winter than in summer, indicating that the mesosphere reacts faster and more sensitively in winter. Comparisons between SFA and SSWF indicate sensitive heights'' above about 80 km for SSWF and below 80 km for SFA. The time-sequence of the effects in different heights, during the initial phase, can be characterized in terms of a gradually down-coming SID layer. (auth)},
doi = {10.1016/0021-9169(74)90130-5},
url = {https://www.osti.gov/biblio/4360739}, journal = {J. Atmos. Terrest. Phys., v. 36, no. 3, pp. 513-524},
number = ,
volume = ,
place = {United Kingdom},
year = {1974},
month = {3}
}