Geomagnetic pulsations accompanied the solar terminator moving through magnetoconjugate region

Abstract

This paper analyzes quasi-periodic geomagnetic field variations in 1÷1000 s period range which are connected with the magnetoconjugate solar terminator action in 2002–2011. The measurements have been made near Kharkiv city. The processing was made separately for summer and winter seasons. Magnetoconjugate solar terminator causes the perturbations relatively to the solar terminator moving at the height of 100 km with the lead time 80 ÷100 min. Dominant periods were 10 ÷12 min and the duration was 50 ÷ 60 min. Their amplitudes attain a value of 1÷2 nT. These variations are transferred from magnetoconjugate region by slow magnetoacoustic waves.