Physics of auroral phenomena : proceedings of the 40th annual seminar, Apatity, 13-17 March, 2017 / [ed. board: N. V. Semenova, A. G. Yahnin]. - Апатиты : Издательство Кольского научного центра РАН, 2017. - 143 с. : ил., табл.

*Physics o f Auroral Phenomena * Proc. XL Annual Seminar, Apatity, pp. 97-99, 2017 © Polar Geophysical Institute, 2017 Polar Geophysical Institute SYNCHRONIZATION OF GEOMAGNETIC AND IONOSPHERIC DISTURBANCES ON THE SUBSTORM PROCESS BACKGROUND O.M. Barkhatova1,2, N.A. Barkhatov2, N.V. Kosolapova2 'Nizhniy Novgorod State University o fArchitecture and Civil Engineering, Nizhniy Novgorod, Russia 2Nizhniy Novgorod State Pedagogical University, Nizhniy Novgorod, Russia Abstract. The phenomena accompanying the event of synchronous night-time ionospheric and geomagnetic disturbances, marked in globally magnetospecific quiet-time on the base of the mid-latitude Kazan station minute data, are analyzed. The dynamic and wavelet spcctra comparison for studied disturbances showed coinciding features of the simultaneous disturbances for layer F2 critical frequency and H, D, Z geomagnetic field components. Therefore it was possible to assume their magnctosonic nature and establish the characteristic periods of observed magnetosonic ULF disturbances in the range of 35-50 minutes. The spatial analysis of noted magnetosonic disturbances with use of geomagnetic data obtained at stations located at different latitudes and longitudes toward to Kazan station demonstrated the isotropy o f founded magnctosonic waves. This allows classifying them as fast magnetosonic disturbances. It is shown that the studied event occurs under substorm development conditions. The causes establishment of intramagnetospheric magnetohydrodynamic (MHD) disturbance is an important goal of solar-terrestrial physics. The appearance of magnetosound disturbances in the magnetosphcrc-ionosphcric medium is commonly associated with development of geomagnetic storm. MHD disturbances in the magnetosphere and ionospheric conductive layers can also be associated however with other high-energy processes. In studies [Barkhatova et al., 2009; Barkhatova et al., 2015], for example, magnetosound type waves, generated by an eastward electrojet and earthquakes of large magnitude were detected. At the same time in addition to geomagnetic field disturbances, synchronous disturbances in ionospheric conductive layer F2 in the ULF range were observed. The present study is devoted to the analysis o f phenomena accompanying the event o f synchronous night time ionospheric and geomagnetic disturbances, detected in the globally magneto-quiet time at the mid-latitude station Kazan (55.78° N, 49.01° E). The search of synchronous ionospheric and geomagnetic disturbances was performed on ionospheric vertical sounding data and data o f geomagnetic field H, D, and Z components with a minute resolution for the interval September 1-4, 2014. The coinciding features of F2 layer critical frequency and the geomagnetic field components simultaneous disturbances as a result of dynamic spectra and wavelet patterns comparison of studied disturbance for September 3, 2014 were found. For other days (1,2 and 4 September) in the night time region (+ 3 GMT) there is no pronounccd ionospheric disturbance. Fig. 1 shows the critical frequency foF2 and the geomagnetic field H component wavelet spectra for Kazan station, received for September 3, 2014 during the night time interval (00.00 to 02.00 UT). The black arrows show the maxima coincidence of ionospheric and geomagnetic field H component disturbances for the interval 01.17 - 01.55 UT. The best coincidence of considered disturbances was noted for periods from 15 to 30 minutes. The fact of simultaneous disturbances for foF2 and the geomagnetic field components coincide allow us to assume their magnetosound nature. The question of relation for considered disturbances to SMS (slow magnetosound), more likely associated to geomagnetic field force line, or to an isotropic FMS (fast magnetosound) type can be solved by spatial analysis of disturbance wavelet spectra received at stations with different latitudes and longitudes from Kazan. The data of geomagnetic field H and D components were used at stations Sodankyla (67.37 N, 26.63 E), Port Alfred (46.43 S, 51.87 E), Hel (54.61 N, 18.82 E), San Fernando (36.67 N, 5.50 W). The coincidence of spectral maxima for Kazan station critical frequency and geomagnetic field H component at the magneto-conjugated observatory Port Alfred (southern hemisphere) for the analyzed frequency range is established for the studied time interval. This indicates the connection of studied wave phenomenon to the corresponding geomagnetic force line. The comparison of the disturbance spectral features for the critical frequency over Kazan with disturbances of geomagnetic field H, D components at other stations located in a large latitudinal-longitude region also showed cases of analyzed spectral features coincidence. Such isotropic behavior for studied magnetosound waves makes it possible to classify them as fast magnetosound disturbances. The search for a possible source of considered night time mid-latitude synchronous ionospheric and geomagnetic disturbances required the study of outer magnetospheric processes. During the case of foF2 disturbances in Kazan, disturbances of the interplanetary magnetic field Bz component (Bz IMF) were detected in the same frequency range. So it was established that the long-period oscillations of Bz IMF find their manifestation in the ionosphere and geomagnetic field components. Fig. 2 shows the wavelet spectra of the foF2 critical frequency at Kazan station (upper panel) and Bz IMF component for the considered time interval. 97