Temporal development of the magnetic zenith effect

Honary, F. and Borisov, N. and Beharrell, M. and Senior, A. (2011) Temporal development of the magnetic zenith effect. Journal of Geophysical Research, 116 (n/a): A06309. ISSN 0148-0227

Full text not available from this repository.

Abstract

An experimental investigation of the temporal dynamics of the magnetic zenith (MZ) effect associated with ionospheric modification by high-power HF electromagnetic waves is presented. The observed electron temperature enhancement when the heater beam and the UHF radar are directed along the magnetic zenith is at least twice that observed when the heater and radar are both directed vertically. It is shown that the temperature enhancement reaches the stationary state within 10 s after the heater is turned on. Such times (∼5–10 s) are typical for the development of striations with transverse sizes of the order of several meters. Also, the temporal behavior of the ion line spectra is analyzed for the field-aligned and vertical directions of the UHF radar. A new theoretical explanation is suggested for the aspect sensitivity of the electron temperature enhancement that explains the fast manifestation of the MZ effect. Furthermore, it is shown that maximum electron heating is achieved at some intermediate inclination angle of the heater beam between the MZ and the Spitze angle. An estimate of the angle within which the maximum heating effect exists is presented.

Item Type:
Journal Article
Journal or Publication Title:
Journal of Geophysical Research
Additional Information:
©2011. American Geophysical Union. All Rights Reserved.
Uncontrolled Keywords:
/dk/atira/pure/core/keywords/physics
Subjects:
?? physicsearth and planetary sciences (miscellaneous)geophysicsatmospheric sciencespace and planetary scienceqc physics ??
ID Code:
55140
Deposited By:
Deposited On:
18 Jun 2012 09:06
Refereed?:
Yes
Published?:
Published
Last Modified:
15 Jul 2024 12:54