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.

A.A. Mochalov at al. Component* ofmagnetic (i»!d12-07-2006, LYR Figure 3. Variations of the horizontal vector (top diagram) and its ratio to the vertical component for one hour of the heating on July 12. Амплитуда главной оси иинпса палярюацнн Figure 4. Amplitude of artificial emission in horisontal plane (top); variations of the horizontal vector (middle) and its ratio to the vertical component (bottom) for one hour of the heating on July 15, interval 05.30 - 06.30 UT. frequency response o f the magnetometer system is constant in the range 0.2 to 20 Hz. Data analysis is based on standard Fast Fourier Transform (FFT) for 4000 data samples. Dynamic spectra o f the components are used for distinguishing the artificial signal from the background variations. From spectral parameters of the components the amplitude and polarization o f the emissions in horizontal plane were determined. Figure 1 shows the pulsation characteristics from top to the bottom: first diagram presents variations of the amplitude of H- and D-components; second one gives calculated main axis of the polarization ellipse; next plot shows the minor axis to main one ratio; and the angle o f the main axis in horizontal plane is shown at fourth diagram. The pulsation amplitude is rather variable during one hour o f the heating although polarization is very stable. Magnetic field variations recorded at LYR observatory on July 12, 2006 are presented in figure 2, heating interval is denoted by vertical dashed lines. Magnitude o f the variations is up to 100 nT in each component. July 6, 2006 was taken as a quiet day for our study. Variations counted off quiet day level were used for calculations of horizontal vector length and its ratio to vertical component Figure 3 shows at the bottom diagram variations of length of the horizontal vector related with the ionospheric current intensity and its distribution in the ionosphere. Ratio of the horizontal vector to the vertical component is presented in bottom diagram. Approach o f the current system center corresponds significant increasing of the component ratio. These dependencies are in a good correlation, it argues that magnetic variation is accounted for current system dynamics not time dependent intensity. Extreme values o f the ratio correspond to the closest location of the current system center to a magnetometer. Note, that variations of the artificial pulsation amplitude near these moments have minimal values. In contrary minimum o f the ratio producing by moving off currents associated with the artificial signal increasing. Top panel o f figure 4 demonstrates 138