The splitting effect of the mode structure of the ionospheric alfven resonator

1Baru, NA, 1Koloskov, AV, 1Yampolski, Yu.M
1Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Kosm. nauka tehnol. 2015, 21 ;(1):58–63
Section: Physics of the near-earth space
Publication Language: Russian

We analyze the data of continues observations of ionospheric Alfven resonance (IAR) which were carried out since 2010 until 2013 at the Ukrainian Antarctic Station “Academic Vernadskiy” and at the Sayan Solar Observatory (Mondy, Russia). The behavior of IAR fine spectral structure is studied and previously unknown effect of the splitting of several lowest resonance modes is found. Diurnal and seasonal regularities of the observability of this effect as well as its dependence on the phase of the eleven-year cycle of solar activity are investigated. The morphological features of the frequency splitting behavior are analyzed and its main phases as development, stationary section and relaxation are identified. Possible mechanisms of the occurrence of splitting effect are suggested.

Keywords: ionospheric alfven resonator, magnetic field, magnetohydrodynamic waves, splitting effect

1. Baru N. A., Koloskov A. V., Rahmatulin R. A. Multiposition observations of the ionospheric alfven resonance signals. The 1-st Ukrainian Conference «Electromagnetic Methods of Environmental Studies (EMES)-2012»,  P. 133—135 (Kharkiv, 2012) [in Russian]. 
2. Baru N. A., Koloskov A. V., Yampolski Y. M., Pashinin A. Y. Evaluation technique for the F2 layer critical frequency by the difference of ionosphere alfven resonance eigenfrequencies.  Radio Physics and Radio Astronomy.  19 (2), 151—159  (2014) [in Russian].
3. Belyaev P. P., Polyakov S. V., Rapoport V. O., Trakhtengerts V. Yu. Experimental study of the resonant structure of the atmospheric electromagnetic noise spectrum at short-period geomagnetic pulsations.  Izv. vuzov. Radiofizika.  32 (6), 663—672 (1989) [in Russian].
4. Koloskov A. V., Bezrodny V. G., Budanov O. V. et al. Polarization Monitoring of the Schumann Resonances in the Antarctic and Reconstruction of the World Thunderstorm Activity Characteristics.  Radio Physics and Radio Astronomy.  10 (1), 11—29  (2005) [in Russian].
5. Koloskov  A. V.,  Sinitsyn V. G.,  Gerasimova N.N.,  Yampolskii Yu. M. ELF resonant cavities in the geospace as space weather indicators.  Kosm. nauka tehnol., 14 (5), 49—64 (2008) [in Russian].
6. Dudkin D., Pilipenko V., Korepanov V., et al. Electric field signatures of the IAR and Schumann resonance in the upper ionosphere detected by Chibis-M microsatellite.  J. Atmos. and Solar-Terr. Phys117, 81—87 (2014).
7. Molchanov O. A., Schekotov A. Yu., Fedorov E., Hayakawa M. Ionospheric Alfven resonance at middle latitudes: results of observations at Kamchatka. Phys. and Chem., Parts A/B/C. 29 (4-9), 649—655 (2004).
8.  Yahnin A. G., Semenova N. V., Ostapenko A. A., et al. Morphology of the spectral resonance structure of the electromagnetic background noise in the range of 0.1—4 Hz at L = 5.2  Ann. Geophys. 21 (3), 779—786 (2003).