Abstract:
A tri-axial search-coil magnetometer system, a part of SEGMA Array (South European Geomagnetic Array), operates since 2003 at the Geomagnetic Observatory Panagjurishte, Bulgaria. It is designated to measure and collect data for the Earth’s magnetic field variations, specific geomagnetic events and long-term study of ULF signals. These observations provide information on the dynamical processes in the Earth’s magnetosphere, geomagnetic micro-pulsations, fluctuations and storms. Here, we obtained results related to three powerful geomagnetic storms recorded by the search-coil magnetometer during the years 2017-2018. Furthermore, we presented the dynamical spectra in the ULF range of each storm.