Physics of auroral phenomena : proceedings of the 33rd Annual seminar, Apatity, 02 - 05 March, 2010 / [ed.: A.G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2011. - 206 с. : ил.

Study o fgeneration o fartificial magnetic pulsations in Pci range at Spitsbergen amplitude of artificial emission in horisontal plane for July 15, 2006. Middle diagram shows variation of the horizontal vector produced by ionospheric current system. In the bottom part the ratio of the horizontal vector variations to the vertical component ones is presented. Three short lasting maxima is observed in the pulsation amplitude. Again one can see local minimums in the ratio of horizontal component of the disturbances to the vertical one corresponded to the pulsation amplitude maxima. Spatial variations of the current center position influences on the artificial emission amplitude: approach of the current center decreases the pulsation intensity, and vise versa. The same format of data presentation is used for July 11, 2006 experiment, time interval 15.50- 16.50 UT (figure 5). This event is characterized by great value of the ratio of the horizontal vector to the vertical component. It means that current system center is located near magnetometer. Moreover at the end o f the heating run sign o f the ratio is changed, i.e. current crosses the zenith over the magnetometer. For this moment pulsation amplitude has a minimum. Clear maximum in the course of the experiment is observed again at the time of minimum of the component ratio. The experimental findings of this study may summarize as follows: - Artificial magnetic pulsations during heating interval vary rather significant. - These variations are in relation with ionospheric current system dynamics - Approach o f the current system leads to decreasing of the emission amplitude and vise versa. References Chisham, G., Lester, М., Milan, S.E., Freeman, M.P., Bristow, W.A., Grocott, A., McWilliams, K.A., Ruohoniemi, J.M., Yeoman, Т.К., Dyson, P.L., Greenwald, R.A., Kikuchi, Т., Pinnock, М., Rash, J P.S., Sato, N., Sofko, G.J., Villain, J.-P., and Walker, A.D. М.: A decade of the Super Dual Auroral Radar Network (SuperDARN): scientific achievements, new techniques and future directions, Surv. Geophys., 28, 33-109,2007. Greenwald, R.A., Baker, K.B., Dudeney, J.R., Pinnock, М., Jones, T.B., Thomas, E.C., Villain, J.-P., Cerisier, J.-C., Senior, C., Hanuise, C., Hunsucker, R.D., Sofko, G., Koehler, J., Nielsen, E., Pellinen, R., Walker, A.D.M., Sato, N., and Yamagishi, H.: DARN/SUPERDARN A global view of the dynamics of high-latitude convection, Space Sci. Rev., 71, 761-796, 1995 Mochalov, A.A., and A.B. Pashin, Features o f generation o f artificial magnetic pulsation in Pci range at Spitsbergen, Vestnik KSC, Apatity, 2010, p. 87 -97. Pashin, A.B., E.G. Belova, and W.B. Lyatsky, Magnetic pulsation generation by a powerful ground-based modulated HF radio transmitter, J. Atmos. Terr. Phys., 57, 245-252, 1995. Ruohoniemi, J.M. and Baker, K.B.: Large-scale imaging of high latitude convection with Super Dual Auroral Radar Network HF radar observations, J. Geophys. Res., 103, 20797—20811, doi: 10.1029/98JA01288, 1998. Амплитуда главкой оси ш ш ш палфиыции Время 15.50-16.50 UT11-07-1006, ю х Figure 5. The same as fig. 4, but for July 11, 2006 experiment. 139