Pc1 hydromagnetic emissions of chevron type


  • Parkhomov Vladimir Alexandrovich Department of Mathematical Methods and Digital Technologies, Baikal State University, Irkutsk, Russia https://orcid.org/0000-0004-0637-8979
  • Tsegmed Battuulai Department of Geomagnetism, Institute of Geophysics and Astronomy, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
  • Dovbnya Boris Victorovich Borok Geophysical Observatory, O.Yu. Sсhmidt Institute of Physics of the Earth, Russian Academy of Sciences, Russia
  • Khomutov Sergey Yurievich Geophysical Observatory Paratunka, Institute of Cosmophysical Research and Radio Wave Propagation, of the Far Eastern Branch, Russian Academy of Sciences, (IKIR) FEB RAS),Russia
  • Eselevich Victor Grigorieivich Department of Solar Physics, Institute of Solar-Terrestrial Physics, Siberian Branch (ISTP SB), Russian Academy of Sciences, Irkutsk, Russia
  • Glinskyi Igor Yurievich Faculty of Mathematical Methods and Computational Techniques, Baikal State University, Irkutsk, Russia




Pc1geomagnetic pulsations, frequency separation of spectrum, ion fluxes, particle drift from the magnetotail, wave- particle interaction


The article presents the results of studying novel bursts of ULF emissions within 0.5–2.5 Hz (Pc1 geomagnetic pulsations) with a simultaneous increase (~0.01 Hz/min) and decrease in frequency (~0.01 Hz/min) lagging by ~5÷10 min from the initial mean frequency (~0.6 Hz). From their formal resemblance with the stripes on military officer uniforms, these emissions are called Pc1 chevrons. The bursts were observed during strong short-term geomagnetic disturbances (~1 hour): substorms with high gradient of ionospheric currents+ intensification (dD/dt or dH/dt ~1–1.3 nT/s).

We present the main parameters and couplings of these emissions with substorm geophysical phenomena of 11.02.1985, 06.04.1997 and 18.07.2013 events. Polar satellite observations of auroras are compared with LANL-91, 94 and THEMIS-A observations of charged particle fluxes. Possible mechanisms generating oscillations are also discussed.


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How to Cite

Alexandrovich, P. V., Battuulai, T., Victorovich, D. B., Yurievich, K. S., Grigorieivich, E. V., & Yurievich, G. I. (2023). Pc1 hydromagnetic emissions of chevron type. Proceedings of the Mongolian Academy of Sciences, 63(04), 1–15. https://doi.org/10.5564/pmas.v63i04.3430