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Information × Registration Number 0209U006074, 0106U001550 , R & D reports Title Modeling of reaction of the ionosphere on the perturbation of a natural origin popup.stage_title Head Tirnov O, Registration Date 21-01-2009 Organization Kharkov National University named after V.N.Karazin popup.description2 Seintific report: 78 pages, 21 figures, 6 tables, 111 references. An object of the research is the parameters of ionospheric plasma and near-earth space under quiet conditions and during perturbations of a natural origin. The work aim is a study of features of development of the ionospheric perturbations under influense of the natural factors and their accounting in the ionospheric models. The basic results. 1. The features of variations of the electron concentration N in midlatitude ionospheric D-region during various perturbations are obtained and explained on the base of observations by a method of partial reflections and numerical estimations. So, the solar eclipse (SE) cause the reduce in usual dayly maxima N, increase N through tens minutes after a beginning of the SE and quasiperiodic increases in N by 2-3 times on heights of 81-84 km. These processes may be caused by fluxes of electrons from a magnetosphere with 40-80 кеV energies, density fluxes р ~ 107 - 108 м-2с-1. The presence of significant quasiperiodic N(z, t) variations with periods Т = 40-45 minutes is confirmed during magnetic storms and several days after their termination. It is possible to explain these variations N(z, t) by the increase of proton and electron fluxes from a magnetosphere up to values р ~ 107-109 м-2 с-1. Also, during magnetic storms the response change of ionospheric D-region on the solar terminator passing is shown. 2. The investigation of the ionospheric F2-region by registrations of navigation satellite signals have confirmed a possibility of a local latitudinal maxima in the total electron content (TEC) near geographical latitude 50 N. The amplitude of local maxima considerably varies by day to day with a period of 3-4 days irrespective of the solar activity level. By the spectral analysis, the presence of common periods in variations of the TEC and atmospheric pressure is established, it may be explained a possibility of the lower atmosphere processes influence (first of all planetary waves) on an ionosphere evenwithout the high-power processes (tornado, high-power weather fronts). 3. The new approaches to a research of a fine structure of wave processes in the ionosphere on the base of the Doppler frequency shift measurements using navigation satellite signals and amplitude of signals reflected from the ionosphere are developed. The algorithm for obtaining the amplitude of wave perturbations as well as the vertical wavelength is formulated. The results of the work may be used for developing the atmospheric models, scheduling of radio engineering systems. They will be used also in the lecture courses on Radio Physics, Geophysics and Astronomy. They will be used for a better understanding of physical processes in the ionosphere during perturbations of a natural origin. RADIOPHYSICAL METHODS, IONOSPHERIC PLASMA, SPACE WEATHER, ELECTRON CONCENTRATION, GEOMAGNETIC STORMS, WAVE PERTURBATIONS, PLANETARY WAVES. The way of using the report: under the contract. Kharkiv 61077, Svoboda Sq. 4, Kharkiv V. Karazin National University. Product Description popup.authors popup.nrat_date 2020-04-02 Close