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Information × Registration Number 0304U004092, 0103U004237 , R & D reports Title The establishment of the physical basis for and the development of the regional ionospheric model popup.stage_title Експериментальні дослідження регіональної іоносфери Head Tirnov O, Registration Date 20-03-2004 Organization Kharkov National University named after V.N.Karazin popup.description2 An object of researches is the parameters of ionospheric plasma and near-earth space under quiet conditions and during natural perturbations. The work aim is obtained of new data on variations of the regional ionosphere parameters during natural perturbations and estimating of possibility of their account in ionospheric models.The main results.1. The variations of regional ionosphere parameters are obtained during natural perturbations caused by solar flashes, magnetic storms, atmospheric (thunder-storms, atmospheric waves and others) and litospheric processes. The main part of the measurements is carried out at the radio physical observatory of Kharkiv V. Karazin National University using complex equipment of recording satellite radio beacon signals, remote sounding of the lower ionosphere, Doppler sounding in the HF range. 2. Accuracy of the known global empirical models and ways of its enhance is analyzed. Note that the majority of the authors fix the model shortages, whereas their possible causes have been investigated insufficiently. It is shown that one of the effective ways of enhancing calculation accuracy of radio wave propagations is developing of regional ionospheric models. 3. It is shown that for further enhancing of the model accuracy, the most important is the finding causes of significant deviations of instantaneous values of ionospheric parameters from their median values. The research of the ionosphere during magnetic storms cannot solve these problems completely. The role of planetary and tide waves in diurnal and day-to-day variations of ionospheric F2 region parameters is shown.4. During solar proton events, the are found and explained increase (units - tens times larges) in the average intensities of partial reflection signals coming from ionospheric D-region irregularities at z ~ 70-80 km, the changes in the radio noise intensity, and also the noise and signals variances. The electron density increase by more than 50-100 % for tens of minutes is established. The quantitative evaluations of ionization velocity variation are made.5. Assessments of proton flows using the experimental data on the electron density changes during proton precipitations are used. Their magnitude was found to be ~ 106 - 107 m-2s-1, well agrees the theoretical calculations. Product Description popup.authors popup.nrat_date 2020-04-02 Close