CHARACTERISTICS OF Pc5 PULSATIONS ACTIVITY AT MID LATITUDES DURING DECEMBER 2019
• Prof. DSc. Oleksandr Trofymchuk, UKRAINE
• Prof. Dr. hab. oec. Baiba Rivza, LATVIA
Applied and Environmental Geophysics
Magnetospheric pulsations and the mechanisms underlying their generation are topics under active studies. The Pc5 (f =1.7–6.7 mHz) geomagnetic continuous pulsations, recorded at mid latitudes (L =1.6) during December 2019, with a low level of geomagnetic activity, are analyzed and discussed in this paper. The data sets of the series on geomagnetic field variations recorded at Panagjuriste Geomagnetic Observatory in Bulgaria are analyzed. The spectral characteristics of the pulsations were determined by Continuous Wavelet Analysis (CWT). It is demonstrated that Pc5 pulsation activity appears with all ranges of periods (140-600s) on December 6, 8, and 18, 2019, at time intervals of 02-17 UTC, 14-20 UTC, and 00-16 UTC, respectively. Then, the solar wind (SW) plasma speed, the flow dynamic pressure, and the geomagnetic index Kp are computed for every case of recorded Pc5 pulsations. It is suggested that recorded continuous pulsations in the Pc5 range are due to step-like or sudden increases in solar wind oscillations and variations of the flow dynamic pressure, which precede the appearance of pulsations and drive compressional magnetic field variations in the magnetosphere.
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This study was supported by the Contract No D01-404/18.12.2020 (Project "National Geoinformation Center (NGIC))", financed by the National Roadmap for Scientific Infrastructure 2020-2027 of Bulgaria.
M. Chamati would like to thank to Dr. M. Velante and Dr. E. Pietropaolo from University of L’Aquila, Italy to assistance. We thank the OMNIWEB database for data provided about IMF Bz, Kp index, SW speed, and flow dynamic pressure.
International Multidisciplinary Scientific GeoConference SGEM
SWS Scholarly Society; Acad Sci Czech Republ; Latvian Acad Sci; Polish Acad Sci; Serbian Acad Sci and Arts; Natl Acad Sci Ukraine; Natl Acad Sci Armenia; Sci Council Japan; European Acad Sci, Arts and Letters; Acad Fine Arts Zagreb Croatia; Croatian Acad Sci and Arts; Acad Sci Moldova; Montenegrin Acad Sci and Arts; Georgian Acad Sci; Acad Fine Arts and Design Bratislava; Turkish Acad Sci.