Density of upper atmosphere neutral components and artificial magnetic pulsations in Pc1 range excitation

Mochalov, A. and Pashin, A.

Polar Geophysical Institute, Apatity, Russia

During last decade series with the EISCAT Heating Facility were carried out with the purpose to produce artificial magnetic pulsations in the 0.1 3 Hz frequency range. For several experiments the EISCAT radar provided measurement of ionospheric electric field and electron density. Numerical model of artificial pulsation excitation has been verified. Predicted amplitude of the pulsation is in accordance with the measured values, however model could not explained sporadic nature of the artificial signals. Disturbances of neutral components are a possible way to explain this feature. Numerical modelling shows that variation of the pulsation amplitude can be around 20%. For artificial emissions with intensity being comparable with background noise these variations could lead to disappearance of the artificial pulsations at spectrogram.