Seminars

Lecturer: Tima Sergienko (IRF)
Date: 2008-11-20 10:30
Place: Aniara

Modelling of Optical Emissions Enhanced by the HF Pumping of the Ionospheric F-Region

Dr Tima Sergienko
Swedish Institute of Space Physics

Abstract
Strong enhancement of the optical emissions with excitation threshold from 1.96 eV (630.0 nm from O(1D)) up to 18.75 eV (427.8 nm from N2+(1NG)) have been observed during experiments of the ionosphere modification by high power HF radio waves. Analysis of the optical emission ratios showed clearly that significant part of the ionospheric electrons should be accelerated up to energy of 30 eV and more in the region where the HF radio wave effectively interacts with the ionospheric plasma.. The Monte-Carlo model of electron transport and the optical emission model were used to study the dependence of the optical emission intensity on the acceleration electron parameters and thermosphere-ionosphere composition. Results of this investigation show that ratios of integral intensity of the optical emissions with different excitation threshold have insignificant dependence on the shape of the accelerated electron spectra but depend on thermosphere composition and plasma-to-neutral density ratio.



Created 2008-11-13 11:32:41 by Mats Holmström
Last changed 2008-11-13 12:56:18 by Mats Holmström