Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 16401 10.12737/article_58fd6dfaa04833.19557687 Results of current research Results of current research Results of current research Spectrum of frequency modulation of serpentine emission as a reflection of the solar fluctuation spectrum Spectrum of frequency modulation of serpentine emission as a reflection of the solar fluctuation spectrum Довбня Борис Викторович Dovbnya Boris Viktorovich dovbnya@inbox.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Клайн Борис Ицикович Klain Boris Icikovich klain@borok.yar.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Гульельми Анатолий Владимирович Guglielmi Anatol Vladimirovich guglielmi@mail.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 https://orcid.org/0000-0002-4864-0993 Потапов Александр Сергеевич Potapov Alexander Sergeevich potapov@iszf.irk.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Геофизическая обсерватория «Борок» ИФЗ РАН Борок Россия Borok Geophysical Observatory of IPE RAS Borok Russian Federation Геофизическая обсерватория «Борок» ИФЗ РАН Борок Россия Borok Geophysical Observatory of IPE RAS Borok Russian Federation Институт физики Земли им. О.Ю. Шмидта РАН Москва Россия Schmidt Institute of Physics of the Earth, RAS Moscow Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation 3 1 73 77 https://zh-szf.ru/en/nauka/article/16401/view

We study frequency modulation of serpentine emission (SE), using data from the Vostok Antarctic station. It is shown that the previously observed 5-minute modulation of the SE carrier frequency is the most prominent and stable in the emission spectrum. Frequency fluctuations of this period are present in about 70 % of the total SE observation time under moderately quiet geomagnetic conditions (Kp=0–2). We performed a per-pixel processing of SE dynamic spectra and found that the power spectrum of the signal frequency modulation contains a clearly visi-ble peak at periods close to 5 minutes. A detailed study shows the emission spectrum matching the frequency range of the solar photospheric oscilla-tions. The results of the analysis allow us to conclude that the 5-minute modulation of the SE carrier fre-quency can be viewed as a reflection of photospheric fluctuations with the same period that is typical for the solar eigenoscillations.

We study frequency modulation of serpentine emission (SE), using data from the Vostok Antarctic station. It is shown that the previously observed 5-minute modulation of the SE carrier frequency is the most prominent and stable in the emission spectrum. Frequency fluctuations of this period are present in about 70 % of the total SE observation time under moderately quiet geomagnetic conditions (Kp=0–2). We performed a per-pixel processing of SE dynamic spectra and found that the power spectrum of the signal frequency modulation contains a clearly visi-ble peak at periods close to 5 minutes. A detailed study shows the emission spectrum matching the frequency range of the solar photospheric oscilla-tions. The results of the analysis allow us to conclude that the 5-minute modulation of the SE carrier fre-quency can be viewed as a reflection of photospheric fluctuations with the same period that is typical for the solar eigenoscillations.

 serpentine emission frequency modulation power spectrum photospheric oscillations

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