Physics of auroral phenomena : proceedings of the 36th Annual seminar, Apatity, 26 February – 01 March, 2013 / [ed. board: A. G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2013. - 215 с. : ил., табл.

G.I. Mingaleva and V.S. Mingalev by the action of the ionospheric high-frequency heating facility near Tromso, Scandinavia. The calculations were made for two cases. Firstly, we obtained the distributions of the ionospheric parameters under natural conditions without a powerful high-frequency wave effect. Secondly, the distributions o f the ionospheric parameters were obtained on condition that the ionospheric high-frequency heating facility has been operated during the period of five minutes, with the heater being located on the night side of the Earth on the magnetic meridian of 01.20 MLT. In the second case, powerful high-frequency waves lead to a decrease of about 40% in the electron concentration at the level of the F2-layer peak over the ionospheric heater. The cross sections o f the artificial electron concentration cavity have dimensions of about 100-150 km in the horizontal directions at the levels of the F layer. The artificial electron concentration cavity is stretched in the direction of the magnetic field line for some hundreds of kilometers. Acknow ledgem ents. This work was partly supported by Grant No. 13-01-00063 from the Russian Foundation for Basic Research. References Blaunshtein, N.Sh., Vas’kov, V.V., Dimant, Ya.S. Resonance heating of the F region by a powerful radio wave. Geomagnetism and Aeronomy, 32(2), 95-99, 1992 (Russian issue). Duncan, L.M., Sheerin, J.P., Behnke, R.A. Observations of ionospheric cavities generated by high-power radio waves. Physical Review Letters, 61, 239-242, 1998. Gustavsson, B., Sergienko, Т., Rietveld, M.T., Honary, F., Steen, A., Brandstrom, B.U.E., Leyser, T.B., Aruliah, A.L., Aso, Т., Ejiri, М., Marple, S. First tomographic estimate of volume distribution of HF-pump enhanced airglow emission. Journal o f Geophysical Research, 106, 29105-29124, 2001. Hardy, D.A., Gussenhoven, M.S., Brautigam, D. A statistical model of auroral ion precipitation, Journal of Geophysical Research, 94, 370-392, 1989. Honary, F., Stocker, A.J., Robinson, T.R., Jones, T.B., Stubbe, P. Ionospheric plasma Response to HF radio waves operating at frequencies close to the third harmonic of the electron gyrofrequency. Journal of Geophysical Research 100, 21489-21501, 1995. Kosch, M.J., Pedersen, Т., Rietveld, M.T., Gustavsson, B., Grach, S.М., and Hagfors,T. Artificial optical emissions in the high-latitude thermosphere induced by powerful radio waves: An observational review. Adv. Space Res., 40, 365-376, 2007. Mantas, G.P., Carlson, H.C., La Hoz, C.H. Thermal response of F-region ionosphere in artificial modification experiments by HF radio waves. Journal of Geophysical Research, 86, 561-574, 1981. Mingaleva, G.I., Mingalev, V.S. The formation o f electron temperature hot spots in the main ionospheric trough by the internal processes, Ann. Geophys., 14, 816-825, 1996. Mingaleva, G.I., Mingalev, V.S. Response of the convecting high-latitude F layer to a powerful HF wave. Annales de Geophysique 15, 1291-1300, 1997. Mingaleva, G.I., Mingalev, V.S. Three-dimensional mathematical model of the polar and subauroral ionosphere, pp.251-265, in Modeling o f the upper polar atmosphere processes, eds. V.E. Ivanov, Ya.A. Sakharov, and N.V.Golubtsova, PGI, Murmansk, 1998, (in Russian). Mingaleva, G.I., Mingalev, V.S. Modeling the modification of the nighttime high-latitude F-region by powerful HF radio waves, Cosmic Research, 40(1), 55-61, 2002. Mingaleva, G.I., Mingalev, V.S. Simulation of the modification of the nocturnal high-latitude F layer by powerful HF radio waves. Geomagnetism and Aeronomy, 43(6), 816-825, 2003, (Russian issue). Mingaleva, G.I., Mingalev, V.S., Mingalev, I.V. Simulation study of the high-latitude F-layer modification by powerful HF waves with different frequencies for autumn conditions. Annales de Geophysique 21, 1827- 1838,2003. Mingaleva, G.I., Mingalev, V.S., Mingalev, I.V. Model simulation o f the large-scale high-latitude F-layer modification by powerful HF waves with different modulation, J. Atmos. Sol.-Terr. Phys., 71, 559-568, 2009. Mingaleva, G.I., Mingalev, V.S., Mingalev, O.V. Simulation study of the large-scale modification of the mid­ latitude F-layer by HF radio waves with different powers // Ann. Geophysicae, 30, 1213-1222, doi: 10.5194/angeo-30-1213-201’2, 2012. Pedersen, Т., Esposito, R., Kendall, E., Sentman, D., Kosch, М., Mishin, E., Marshall, R. Observations of artificial and natural optical emissions at the HAARP facility. Ann. Geophysicae, 26, 1089-1099, 2008. Rietveld, M.T., Kosch, M.J., Blagoveshchenskaya, N.F., Kornienko, V.A., Leyser, T.B., Yeoman, Т.К. Ionospheric electron heating, optical emissions, and striations induced by powerful HF radio waves at high latitudes: Aspect angle dependence. J. Geophys. Res., 108 (A4), 1141, doi:10.1029/2002JA009543, 2003. Utlaut, W.F., Violette, E.J. A summary of vertical incidence radio observations o f ionospheric modification. Radio Science 9, 895-903, 1974. 162