Солнечно-земная физика, 2019, том 5, № 2

СОЛНЕЧНО-ЗЕМНАЯ ФИЗИКА 

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ISSN 2412-4737

              DOI: 10.12737/issn. 2412-4737 
              Том 5. № 2. 2019. 148 с. 
              Выходит 4 раза в год 

Учредители: Федеральное государственное бюджетное учреждение науки 
Ордена Трудового Красного знамени Институт солнечно-земной физики 
Сибирского отделения Российской академии наук 

Федеральное государственное бюджетное учреждение «Сибирское отделение Российской академии наук»

SOLAR-TERRESTRIAL PHYSICS 

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of mass media  
from October 17, 2017. ПИ № ФС77-71337 
The edition has been published since 1963 

ISSN 2412-4737

               DOI: 10.12737/issn. 2412-4737 
               Vol. 5. Iss. 2. 2019. 148 p. 

Quarterly

Founders: Institute of Solar-Terrestrial Physics of Siberian Branch of Russian Academy of Sciences 

Siberian Branch of the Russian Academy of Sciences

Состав редколлегии журнала 
 
 
Editorial Board 
 

Жеребцов Г.А., академик —
главный редактор, ИСЗФ СО РАН

Zherebtsov G.A., Academician, Editor-in-Chief, 
ISTP SB RAS

Степанов А.В., чл.-кор. РАН —
заместитель главного редактора, ГАО РАН

Stepanov A.V., Corr. Member of RAS, 
Deputy Editor-in-Chief, GAO RAS

Потапов А.С., д-р физ.-мат. наук —
заместитель главного редактора, ИСЗФ СО РАН

Potapov A.S., D.Sc. (Phys.&Math), 
Deputy Editor-in-Chief, ISTP SB RAS

Члены редколлегии
Members of the Editorial Board  

Алтынцев А.Т., д-р физ.-мат. наук, ИСЗФ СО РАН
Altyntsev A.T., D.Sc. (Phys.&Math.), ISTP SB RAS

Белан Б.Д., д-р физ.-мат. наук, ИОА СО РАН
Belan B.D., D.Sc. (Phys.&Math.), IAO SB RAS

Гульельми А.В., д-р физ.-мат. наук, ИФЗ РАН
Guglielmi A.V., D.Sc. (Phys.&Math.), IPE RAS

Деминов М.Г., д-р физ.-мат. наук, ИЗМИРАН
Deminov M.G., D.Sc. (Phys.&Math.), IZMIRAN

Ермолаев Ю.И., д-р физ.-мат. наук, ИКИ РАН
Yermolaev Yu.I., D.Sc. (Phys.&Math.), IKI RAS

Лазутин Л.Л., д-р физ.-мат. наук, НИИЯФ МГУ
Lazutin L.L., D.Sc. (Phys.&Math.), SINP MSU

Леонович А.С., д-р физ.-мат. наук, ИСЗФ СО РАН
Leonovich A.S., D.Sc. (Phys.&Math.), ISTP SB RAS

Мареев Е.А., чл.-кор. РАН, ИПФ РАН
Mareev E.A., Corr. Member of RAS, IAP RAS

Мордвинов А.В., д-р физ.-мат. наук, ИСЗФ СО РАН
Mordvinov A.V., D.Sc. (Phys.&Math.), ISTP SB RAS

Обридко В.Н., д-р физ.-мат. наук, ИЗМИРАН
Obridko V.N., D.Sc. (Phys.&Math.), IZMIRAN

Перевалова Н.П., д-р физ.-мат. наук, ИСЗФ СО РАН
Perevalova N.P., D.Sc. (Phys.&Math.), ISTP SB RAS

Салахутдинова И.И., канд. физ.-мат. наук,
Salakhutdinova I.I., C.Sc. (Phys.&Math.),

ученый секретарь, ИСЗФ СО РАН
Сафаргалеев В.В., д-р физ.-мат. наук, ПГИ 

Scientific Secretary, ISTP SB RAS
Safargaleev V.V., D.Sc. (Phys.&Math.), PGI 

Сомов Б.В., д-р физ.-мат. наук, ГАИШ МГУ
Somov B.V., D.Sc. (Phys.&Math.), SAI MSU

Стожков Ю.И., д-р физ.-мат. наук, ФИАН
Stozhkov Yu.I., D.Sc. (Phys.&Math.), LPI RAS

Тащилин А.В., д-р физ.-мат. наук, ИСЗФ СО РАН
Tashchilin A.V., D.Sc. (Phys.&Math.), ISTP SB RAS

Уралов А.М., д-р физ.-мат. наук, ИСЗФ СО РАН
Uralov A.M., D.Sc. (Phys.&Math.), ISTP SB RAS

Лестер М., проф., Университет Лестера, Великобритания
Lester M., Prof., University of Leicester, UK

Йихуа Йан, проф., Национальные астрономические
обсерватории Китая, КАН, Пекин, Китай 

Yan Yihua, Prof., National Astronomical Observatories,
Beijing, China 

Панчева Дора, проф., Национальный институт геодезии, 
геофизики и географии БАН, София, Болгария

Pancheva D., Prof., Geophysical Institute, Bulgarian
Academy of Sciences, Sofia, Bulgaria 

Полюшкина Н.А., ответственный секретарь редакции,
ИСЗФ СО РАН

Polyushkina N.A., Executive Secretary of Editorial Board,
ISTP SB RAS 

СОДЕРЖАНИЕ

14-я Китайскo-Российская конференция по космической погоде.

Хайкоу, Китай, 5–9 ноября 2018 г. 

Чэнмин Тань, Биолинь Тань, Йихуа Йан, Вэй Ван, Линьцзе Чэнь, Фэй Лю, Ицзян Доу. Собы
тия с тонкой структурой в микроволновом излучении во время солнечного минимума ……………... 4–10 

Леонович А.С., Цюган Цзун, Козлов Д.А., Юнфу Ван. Альфвеновские волны, возбуждаемые в 

магнитосфере при взаимодействии ударной волны с плазмопаузой ……...…………………………… 
11–16 

Лунюшкин С.Б., Мишин В.В., Караваев Ю.А., Пенских Ю.В., Капустин В.Э. Исследование ди
намики электрических токов и полярных шапок в ионосферах двух полушарий во время геомагнитной бури 17 августа 2001 г. ……………………….........................................................................................

 
17–29 

Дали Ян, Теминь Чжан, Цзихун Ван, Цзяньцин У, Линьмао Ван, Сюй Цзоу, Хунянь Пэн.

Характеристики двойного натриевого слоя над Хайкоу, Китай (20.0° N, 110.1° E) ……………………. 30–34 

Леонович Л.А., Тащилин А.В., Лунюшкин С.Б., Караваев Ю.А., Пенских Ю.В. Изучение источни
ков эмиссии атомарного кислорода 630 нм во время сильных магнитных бурь в ночной среднеширотной ионосфере ……………………………………………………………………………………............

 
35–41 

Белецкий А.Б., Рахматулин Р.А., Сыренова Т.Е., Васильев Р.В., Михалев А.В., Пашинин А.Ю.,

Шиокава К., Нишитани Н. Предварительные результаты синхронной регистрации авроральных и 
геомагнитных пульсаций на станции «Исток» ИСЗФ СО РАН …..………………………………………

 
42–48 

Ша Ли, Йихуа Йан, Чжицзюнь Чень, Вэй Ван. Сравнение результатов моделирования сложен
ной и развернутой логопериодической антенны, используемой для наблюдений Солнца …………….
49–54 

Цзюнь Чэн, Йихуа Йан, Дун Чжao, Лун Сюй. Aлгоритм последовательного масштабирования 

CLEAN для Минъаньтуского спектрального радиогелиографа ………………………………………….
55–62

Международный семинар «Процессы энерговыделения на Солнце и звездах: 
источники и эффекты». Иркутск, Институт солнечно-земной физики СО РАН, 
10–12 октября 2018 г. 

Чжэнхуа Хуан, Бо Ли, Лидун Ся. Наблюдения мелкомасштабных энергетических событий в 

солнечной переходной области: взрывных событий, всплесков ультрафиолетового излучения и 
струйных явлений …………………………………………………………………………………………… 63–73

Статьи, не относящиеся к материалам конференций 

Петухова А.С., Петухов С.И. Тороидальные модели магнитного поля с винтовой структурой …
74–81

Смирнов В.М., Смирнова Е.В. Ионосферные эффекты двух солнечных вспышек максимума 23-го

и минимума 24-го циклов солнечной активности ……………………………………………………........ 82–88 

Дмитриенко И.С. Возмущения второго порядка в альфвеновских волнах в приближении холод
ной плазмы …………………………………………………………………………………………………...
89–96 

Лунюшкин С.Б., Пенских Ю.В. Диагностика границ аврорального овала на основе техники

инверсии магнитограмм ……………………………………………………………...................................... 97–113 

Захаров В.И., Пилипенко В.А., Грушин В.А., Хамидуллин А.Ф. Влияние тайфуна Vongfong

2014 на ионосферу и геомагнитное поле по данным спутников Swarm: 1. Волновые возмущения 
ионосферной плазмы ………………………………………………………………………………………... 114–123

Кушнаренко Г.П., Яковлева О.Е., Кузнецова Г.М. Электронная концентрация на высотах ионо
сферного слоя F1 в период 2007–2014 гг. над Норильском …………………………………………….... 124–128

Кушнаренко Г.П., Яковлева О.Е., Кузнецова Г.М. Геомагнитные возмущения на высотах слоя 

F1 ионосферы в различных условиях солнечной активности над Норильском ………………………… 129–132

Лоптева Л.С., Кушталь Г.И., Прошин В.А., Скоморовский В.И., Фирстов С.В., Химич В.А., 

Чупраков С.А. Хромосферный K СаII телескоп Байкальской астрофизической обсерватории. 
Новый свет …………………………………………………………………………………………………... 133–147

CONTENTS

14th China-Russia Space Weather Workshop.

November 5–9, 2018, Haikou, China 

Chengming Tan, Baolin Tan, Yihua Yan, Wei Wang, Linjie Chen, Fei Liu, Yujiang Dou. Fine struc
ture events in microwave emission during solar minimum ………………………………………………….. 4–10 

Leonovich A.S., Zong Q.-G., Kozlov D.A., Wang Y.F. Alfvén waves in the magnetosphere generated by 

shock wave / plasmapause interaction ……......................................................................................................... 
11–16 

Lunyushkin S.B., Mishin V.V., Karavaev Yu.A., Penskikh Yu.V., Kapustin V.E. Studying the dynam
ics of electric currents and polar caps in ionospheres of two hemispheres during the August 17, 2001 geomagnetic storm ………………….......................................................................................................................

 
17–29 

Dali Yang, Tiemin Zhang, Jihong Wang, Jianqing Wu, Linmao Wang, Xu Zou, Hongyan Peng.

Characteristics of double sodium layer over Haikou, China (20.0° N, 110.1° E) ……………………………. 30–34

Leonovich L.A., Tashchilin A.V., Lunyushkin S.B., Karavaev Yu.A., Penskikh Yu.V. Studying 630 nm

atomic oxygen emission sources during strong magnetic storms in the night mid-latitude ionosphere ……. 
35–41 

Beletskii A.B., Rakhmatulin R.A., Syrenova T.Ye., Vasilev R.V., Mikhalev A.V., Pashinin A.Yu., 

Shiokawa K., Nishitani N. Preliminary results of simultaneous recording of auroral and geomagnetic pulsations at the ISTP SB RAS station Istok ……..............................................................................................................

 
42–48 

Sha Li, Yihua Yan, Zhijun Chen, Wei Wang. Comparing simulated results of folded and unfolded log
periodic antenna used for observing the Sun …..………................................................................................... 49–54 

Jun Cheng, Yihua Yan, Dong Zhao, Long Xu. Scale sequentially CLEAN for Mingantu Spectral

Radioheliograph …………………………………………………………………………….………………… 55–62

The International Workshop “Eruptive energy release processes on the Sun and stars: origins and effects”. 
October 10–12, 2018. Institute of Solar-Terrestrial Physics SB RAS, Irkutsk, Russia 

Zhenghua Huang, Bo Li, Lidong Xia. Observations of small-scale energetic events in the solar transi
tion region: explosive events, UV bursts, and network jets ………………………………………………….
63–73

Articles not related to materials of conferences 

Petukhova A.S., Petukhov S.I. Toroidal models of magnetic field with twisted structure ………………
74–81

Smirnov V.M., Smirnova E.V. Ionospheric effects of two solar flares in the maximum of solar cycle 23 

and in the minimum of solar cycle 24 ………………........................................................................................ 82–88 

Dmitrienko I.S. Second-order perturbations in Alfvén waves in cold plasma approximation ………….
89–96

Lunyushkin S.B., Penskikh Yu.V. Diagnostics of auroral oval boundaries on the basis of the magneto
gram inversion technique ……………………………………………………………………........................... 97–113 

Zakharov V.I., Pilipenko V.A., Grushin V.A., Khamidullin A.F. Impact of typhoon Vongfong 2014 on 

the ionosphere and geomagnetic field according to Swarm satellite data: 1. Wave disturbances of ionospheric 
plasma ……………………………………………………………………........................................................

 
114–123

Kushnarenko G.P., Yakovleva O.E., Kuznetsova G.M. Electron density in the F1 layer over 

Norilsk in 2007–2014……………………………………………………………………................................. 124–128

Kushnarenko G.P., Yakovleva O.E., Kuznetsova G.M. Geomagnetic disturbances at F1-layer heights 

under different solar activity conditions over Norilsk ……………………………………………………….. 129–132

Lopteva L.S., Kushtal G.I., Proshin V.A., Skomorovsky V.I., Firstov S.V., Khimich V.A., Chuprakov S.A.

Chromospheric K CaII telescope of Baikal Astrophysical Observatory. New light …………………………. 133–147

Солнечно-земная физика. 2019. Т. 5. № 2 
 
 
 
        Solnechno-zemnaya fizika. 2019. Vol. 5. Iss. 2 

4 

УДК 523.98 
 
 
 
 
 
 
 
       Поступила в редакцию 26.02.2019 
DOI: 10.12737/szf-52201901 
 
 
 
 
 
       Принята к публикации 22.04.2019 

 
СОБЫТИЯ С ТОНКОЙ СТРУКТУРОЙ В МИКРОВОЛНОВОМ ИЗЛУЧЕНИИ 
ВО ВРЕМЯ СОЛНЕЧНОГО МИНИМУМА 

FINE STRUCTURE EVENTS IN MICROWAVE EMISSION 
DURING SOLAR MINIMUM 
 
Чэнмин Тань 
Национальные астрономические обсерватории Китая, 
Пекин, Китай, tanchm@nao.cas.cn 
Университет Китайской академии наук, 
Пекин, Китай, tanchm@nao.cas.cn 
Биолинь Тань 
Национальные астрономические обсерватории Китая, 
Пекин, Китай, bltan@nao.cas.cn 
Университет Китайской академии наук, 
Пекин, Китай, bltan@nao.cas.cn 
Йихуа Йан 
Национальные астрономические обсерватории Китая, 
Пекин, Китай, yyh@nao.cas.cn 
Университет Китайской академии наук, 
Пекин, Китай, yyh@nao.cas.cn 
Вэй Ван 
Национальные астрономические обсерватории Китая, 
Пекин, Китай, wwang@nao.cas.cn 
Линьцзе Чэнь 
Национальные астрономические обсерватории Китая, 
Пекин, Китай, ljchen@nao.cas.cn 
Фэй Лю 
Национальные астрономические обсерватории Китая, 
Пекин, Китай, feiliu@nao.cas.cn 
Ицзян Доу 
Университет Сучжоу, 
Сучжоу, Китай, douyj@suda.edu.cn 

Chengming Tan 
National Astronomical Observatories, Chinese Academy of Sciences, 
Beijing, China, tanchm@nao.cas.cn 
University of Chinese Academy of Sciences, 
Beijing, China, tanchm@nao.cas.cn 
Baolin Tan 
National Astronomical Observatories, Chinese Academy of Sciences, 
Beijing, China, bltan@nao.cas.cn 
University of Chinese Academy of Sciences, 
Beijing, China, bltan@nao.cas.cn 
Yihua Yan 
National Astronomical Observatories, Chinese Academy of Sciences, 
Beijing, China, yyh@nao.cas.cn 
University of Chinese Academy of Sciences, 
Beijing, China, yyh@nao.cas.cn 
Wei Wang 
National Astronomical Observatories, Chinese Academy of Sciences, 
Beijing, China, wwang@nao.cas.cn 
Linjie Chen 
National Astronomical Observatories, Chinese Academy of Sciences, 
Beijing, China, ljchen@nao.cas.cn 
Fei Liu 
National Astronomical Observatories, Chinese Academy of Sciences, 
Beijing, China, feiliu@nao.cas.cn 
Yujiang Dou 
Soochow University, 
Suzhou, China, douyj@suda.edu.cn 

 
Аннотация. Солнечный минимум представляет 
собой период, для которого характерно несколько 
меньшее количество солнечных пятен и эрупций. 
Раньше этому периоду уделялось меньше внимания. 
Поскольку радиосигнал быстро откликается на изменение солнечной плазмы и магнитного поля, мы 
провели комплексный анализ спектральных данных 
высокого разрешения, полученных SBRS и MUSER: 
1) поиск солнечных радиовсплесков различных видов за последние солнечные минимумы (2007–2009 
и 2016–2018 гг.); 2) анализ нескольких типичных 
радиовсплесков, отрицательного и положительного 
дрейфующих всплесков, например, событий, произошедших 22.11.2015 и 29.08.2016, событий со 
сверхтонкой спектральной структурой с минивспышкой и даже без солнечных пятен, например, событий, зарегистрированных 28.03.2008. и 04.07.2017. 
Эти результаты показали, что во время солнечных 
минимумов было много радиовсплесков с тонкой 
структурой. Эти события происходили не только в 
мощных вспышках, но и в слабых (класс C и B по 
GOES) или даже без вспышек, но в областях, связанных со слабым уярчением или выбросом. Мы полагаем, что слабые солнечные радиовсплески, наблюдаемые телескопами с высокой чувствительностью 

Abstract. The solar minimum is a period with a relatively smaller number of sunspots and solar eruptions, and 
has been less studied before. Since the radio signal rapidly 
responds to the change of solar plasma and magnetic field, 
we perform  a comprehensive analysis of high resolution 
spectrum data from SBRS and MUSER: 1) a search for 
solar radio bursts of different kinds in recent solar minima (2007–2009 and 2016–2018); 2) an analysis of several typical radio burst events, negative and positive 
drifting bursts, for example the November 22, 2015 and 
August 29, 2016 events; superfine spectral structure 
events with mini-flares and even without sunspots, for 
example the March 28, 2008 and July 04, 2017 events. 
These results show that there were many radio bursts 
with a fine structure during solar minima. These events 
occurred not only in powerful flares, but also in faint 
flares (class C and B by GOES) or even without flares, 
but in regions related to weak brightenings or ejecta. We 
assume that the weak solar radio bursts observed by 
telescopes with high sensitivity and low interference 
will help us to understand the basic physical characteristics of small-scale solar eruptions. 
Keywords: solar minimum, flare, radio burst, spectrum, fine structure. 

Чэнмин Тань, Биолинь Тань, Йихуа Йан, Вэй Ван, 
 
              Chengming Tan, Baolin Tan, Yihua Yan, Wei Wang, 
Линьцзе Чэнь, Фэй Лю, Ицзян Доу 
 
 
 
              Linjie Chen, Fei Liu, Yujiang Dou 

5

и низкой интерференцией, помогут нам понять основные физические характеристики мелкомасштабных солнечных эрупций. 
Ключевые слова: солнечный минимум, вспышка, 
радиовсплеск, спектр, тонкая структура. 

 
 
 

 

 
INTRODUCTION 

In recent years, the study of solar minima has mainly 
focused on solar activities [Lingri et al., 2016], magnetic 
field characteristics [de Toma et al., 2000], etc. With a 
series of high performance solar instruments developed, 
it has been found that there are many small-scale eruptions in solar minima. The solar dynamo shows that 
features of magnetic activity at solar minimum are likely 
to determine the intensity and duration of the next solar 
cycle [Tan, 2019]. The study of the radio emission at 
solar minimum mainly focuses on characteristics of 
radiation of the quiet Sun, paying little attention to nonthermal explosion phenomena. A reason is that there are 
few active regions, weak magnetic fields, and radio 
bursts during solar minima. Tan et al. [2013] have analyzed all observations made with the China Solar 
Broadband Radio Spectrometer (SBRS) [Fu et al., 1995, 
2004; Ji et al., 2000] from 1997 to 2011. It has been 
found that only flares above M4.0 class are accompanied by microwave bursts by 100 %. Some low-class 
flares occur without microwave bursts. There are few 
radio bursts recorded in 2008–2009. On the other hand, 
the instrument is sensitive to electromagnetic interference. In the data analysis, it is difficult to distinguish 
weak bursts from interference. Recently, we have tried 
to improve data processing methods and software [Chen 
et al., 2016], gained more experience in identifying 
weak bursts from interference signals. When analyzing 
high resolution observation data during the solar minima, 
more bursts have been found. It has been established 
that radio bursts and superfine spectral structures still 
occur in a mini-flare or weak magnetic field region. 
There are many studies [Chernov, 2006, 2011; 
Altyntsev, 2007, 2008] of the radio fine spectral structures which happen during strong solar flares. Zhdanov 
and Zandanov [2015] have found that fine structures are 
detected both during solar flares accompanied by microwave broadband emission and during weak solar 
flares when the microwave broadband emission is absent. Thus, we try to study radio fine spectral structure 
events during solar minima because there are almost no 
works on this case for now. As the preliminary results 
we present four events here. 
 
INSTRUMENT AND OBSERVATION 

We study the radio spectrum observed by SBRS 
during the solar minima of 2007–2009 and 2016–2018. 
The SBRS1 spectrometer has been upgraded three times 
[Tan et al., 2015]. The newest receiver was developed 
by Soochow University and has been working since 
2013. Now SBRS1 parameters are as follows: 
• Antenna diameter: 7.4 m; 
• Frequency band: 1.10–2.10 GHz; 
• Frequency resolution: 2.78 MHz; 

• Frequency channels: 360; 
• Time cadence: 5 ms; 
• Accuracy of polarization: <10 %. 
Hundreds of solar radio bursts were identified during 
the 2007–2009 and 2016–2018 solar minima; some of 
them were accompanied by very weak flares (miniflares). As a comparison, we study the radio spectrum 
observed 
by 
Mingantu 
Spectral 
Radioheliograph 
(MUSER) [Yan et al., 2016]. MUSER is a new aperture 
synthesis solar radio telescope array, which can observe 
the full Sun in centimeter-decimeter wavelengths with 
high resolutions and dual polarization. The maximum 
baseline is 3 km, which gives the maximum spatial resolutions from 63'' to 1.7'' at different frequencies. 
MUSER is composed of two sub-arrays: MUSER-I and 
MUSER-II with frequency ranges 0.4–2.0 GHz and 2.0–
15.0 GHz respectively. The whole array is composed of 
100 antennas distributed in three spiral arms with the 
longest baseline of 3.0 km. The dynamic range is designed to be 25 dB, the temporal resolution is 25 ms, 
and the frequency resolution is 25 MHz. The measurement accuracy of the dual circular polarization is about 
10 %. MUSER-I has been working since 2014; and 
MUSER-II, since the summer of 2016. In this paper, we 
only adopted the spectrograms obtained by MUSER-I.  

The GOES soft X-ray flux [Bornmann et al., 1996], 
SDO AIA [Pesnell et al., 2012] image, and RHESSI 
[Lin et al., 2002] hard X-ray observations are also used 
here for analysis. 
 
DATA AND EVENT ANALYSIS 

Few radio burst events have previously been recorded from SBRS data during solar minima. The bursts 
were weak and had short duration. Due to the development of calibration [Tan et al., 2015], interference 
cleaning, and image recognition [Chen et al., 2016], 
more and more weak solar radio bursts have been observed and identified from observations with new telescopes. Here we illustrate four examples. Among them 
are two events with negative and positive drift velocities, which are accompanied by very weak GOES soft 
X-ray flares. The third event is type III bursts with a 
very weak flare identified, and the fourth event is superfine structure bursts with no sunspots reported from the 
full-Sun observations from March 3, 2017 to July 4, 
2017. 
The November 22, 2015 event is shown in Figure 1. 
The radio fine structure occurred between 04:51:27 and 
04:51:41 UT. First, groups of narrowband type III bursts 
drifted slowly from high to low frequencies, and then 
they drifted slowly and reversely to high frequencies. 
It is also very interesting that most of individual type III 
bursts also drifted in the same way as the groups, i.e. 
they first drifted from high to low frequencies and 
then reversely to high frequencies. These groups of type III 

События с тонкой структурой в микроволновом излучении… 
                  Fine structure events in microwave emission… 

6

 

Figure 1. The November 22, 2015 event. The top panel is the GOES soft X-ray at 1.0–8.0 Å. The black arrow indicates 
the time of corresponding radio fine structure spectrum shown on two bottom panels. The radio spectrum is from MUSER 
observation 
 
low to high frequencies, then drifted up and down, and 
afterwards drifted slowly upward to high frequencies. 
It is also very interesting that most of the individual type III 
bursts also drifted in the same way as the groups, i.e. 
they first drifted from low to high frequencies, then drifted upward to low frequencies. These groups of type III 
bursts occurred just at the maximum of a moderate flare 
(C2.2 class indicated by an arrow on the top panel of 
Figure 2). Thus, we may assume that electron beams 
were accelerated within the magnetic reconnection region, and traveled up and down along the magnetic 
loop; some of them managed to escape to the upper 
corona. 
The March 28, 2008 event is shown in Figure 3. The 
radio fine structure occurred between 00:14:30 and 
00:15:05 UT. It is a group of type III bursts. Each individual group of type III bursts drifted fast downward to 
high frequencies. This group of type III bursts has no 
corresponding flare identified nearby. The upper two 
panels of Figure 3 indicate that there is no SXR flare 
but a weak HXR flare at 6–12 KeV observed by 
RHESSI approximately at the same time as the type III 
bursts were recorded. The two bottom panels are the EIT 
195 Å image after running differentiation, superposed 
onto the 6–12 KeV RHESSI image between 01:11:22 
and 01:17:22 UT. There are no RHESSI images for 
00:00–00:30 UT. 
The July 04, 2017 event is shown in Figure 4. The 
radio fine structure occurred between 01:07:46.14 and 

01:07:46.55 UT, for less than 500 milliseconds. Each 
individual burst lasted for <20 ms. It is a little difficult 
to identify if there is a drift or not for each individual 
group of type III bursts since its duration is approximately equal to the time resolution. The first panel of 
Figure 4 shows the radio fine structure (time is indicated 
by an arrow) is just before the maximum of a small flare 
(B2.0 class). There are no sunspots or active regions 
reported for this group of radio fine structures. The AIA 
171 Å full-disk solar image exhibits no remarkable 
flares or ejecta within 01:00–01:10 UT. The AIA 171 Å 
west limb images (bottom four panels) display weak 
brightening near the limb. There are no MUSER observations for the time of this radio fine structure. 
 
RESULTS AND DISCUSSION 

In this work, we only report that there were some radio 
bursts accompanied by weak solar flares (mini-flares) 
during solar minima. From the four events analyzed, 
several results can be summarized as follows: 
1. During solar minima, the radio burst spectrum 
also exhibited many fine structures, including groups of 
drifting type III bursts, etc. They occurred not only during the main solar flare, but also during small flares, 
mini-flares, and even without obvious flares and sunspots. Some radio fine structures occurred without obvious flares or sunspots, but still with weak EUV brightening or ejecta, or with HXR microflare. 

Чэнмин Тань, Биолинь Тань, Йихуа Йан, Вэй Ван, 
 
              Chengming Tan, Baolin Tan, Yihua Yan, Wei Wang, 
Линьцзе Чэнь, Фэй Лю, Ицзян Доу 
 
 
 
              Linjie Chen, Fei Liu, Yujiang Dou 

7

 

Figure 2. The August 29, 2016 event. The top panel is the GOES soft X-ray at 1.0–8.0 Å. The black arrow indicates the time of 
corresponding radio fine structure spectrum shown on four bottom panels. Two panels of radio spectrum are from MUSER observation. Another two panels of radio spectrum are from SBRS1 observation 
 
2. The first two radio fine structure events are 
groups of type III bursts drifting up and down globally, 
while the third one are groups of type III bursts drifting 
down globally. For all the three events, the individual 
type III burst drifted in the same way as that drifting 
globally. The fourth one is a superfine structure event 
with short group duration of <500 ms and short individual duration of <20 ms. Some structures have unusual 

duration of <5 ms and strong intensity. It is difficult to 
identify if the individual structure drifted or not. 
The globally drifting type III bursts might have similar physical evolvement as the drifting pulsation structures (DPSs) which usually happened in the initial phase of 
a flare. DPSs [Karlicky, 2004; Tan et al., 2008] usually are 
groups of up and down drifting bursts. Karlicky [2004] 
has explained the DPS map of the evolution of the primary 

События с тонкой структурой в микроволновом излучении… 
                  Fine structure events in microwave emission… 

8

 

Figure 3. The March 28, 2008 event. The first panel is the GOES soft X-ray at 1.0–8.0 Å. The second panel plots the profile of 
GOES soft X-ray and radio flux observed by SBRS at 2940 MHz. The RHESSI 6–12 KeV profile is also plotted on both of the panels. 
On the third panel is the radio fine structure spectrum observed by SBRS at the 2600–3800 MHz band. Two bottom panels present the EIT 195 Å image after running differentiation, superposed onto the RHESSI image  
 
and secondary plasmoids formed due to tearing and 
coalescence instabilities in the current sheet during the 
reconnection process. Melnikov et al. [2002, 2005] 
suggested that the flare loop is filled with dense plasma with the density number n0≈1011 cm–3 and that accelerated electrons are concentrated in the upper part of 
the flare loop. Zhdanov and Zandanov [2015] have reported that radio fine structures can be detected during weak solar flares when the microwave broadband 
emission is absent. Nakariakov et al. [2018] have 
reported on radio quasi-periodic pulsations (QPP) in 
a B2-microflare. QPP are likely to be caused by the superposition of the signals generated at local electron 

plasma frequencies by the interaction of nonthermal 
electrons with plasma at footpoints. All these help us to 
understand that radio fine structures can still occur in a 
weak flare during solar minimum as long as an abundance of electrons are accelerated during the reconnection along the loop with dense plasma. Thus, the fine 
structure can still be observed with a high-sensitivity 
and resolution telescope.  
Our future work will compare more events with other observations at a similar frequency band, for example 
SSRT [Smolkov et al., 1986; Grechnev et al., 2003] 
and YNRS [Gao et al., 2014], and study the flare loop 
with radio image observations from MUSER and NORH 

Чэнмин Тань, Биолинь Тань, Йихуа Йан, Вэй Ван, 
 
              Chengming Tan, Baolin Tan, Yihua Yan, Wei Wang, 
Линьцзе Чэнь, Фэй Лю, Ицзян Доу 
 
 
 
              Linjie Chen, Fei Liu, Yujiang Dou 

9

 

Figure 4. The July 04, 2017 event. The top panel is the GOES soft X-ray at 1.0–8.0 Å. The black arrow indicates the time of corresponding radio fine structure spectrum observed by SBRS at 1100–1900 MHz band, shown on the second panel. The four bottom panels are SDO AIA 171 Å images after running differentiation 
 
[Nakajima, 1994]. We can expect that the weak radio 
bursts observed with the high-sensitivity low-interference 
telescope will help us to understand physical characteristics of small-scale eruptions and nano-flares, and will 
further expand our understanding of solar radio emission and solar magnetic field. 
This work is supported by NSFC grants Nos. 
11373039, 
11433006, 
11573039, 
11661161015, 
11790301, and 11790305. We thank NGDC, Solarmonitor, SWPC, and Space Weather Prediction Center for 
online data. 
 
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Color Figures are available in the article electronic version. 

How to cite this article: 
Chengming Tan, Baolin Tan, Yihua Yan, Wei Wang, Linjie Chen, 
Fei Liu, Yujiang Dou. Fine structure events in microwave emission 
during solar minimum. Solnechno-zemnaya fizika. 2019. Vol. 5. Iss. 2. 
P. 4–10. DOI: 10.12737/szf-52201901. 

Солнечно-земная физика. 2019. Т. 5. № 2 
 
 
 
        Solnechno-zemnaya fizika. 2019. Vol. 5. Iss. 2 

11 

УДК 523.62-726, 533.9, 551.510.537 
 
 
 
 
       Поступила в редакцию 12.02.2019 
DOI: 10.12737/szf-52201902 
 
 
 
 
 
       Принята к публикации 29.03.2019 

 
АЛЬФВЕНОВСКИЕ ВОЛНЫ, ВОЗБУЖДАЕМЫЕ В МАГНИТОСФЕРЕ 
ПРИ ВЗАИМОДЕЙСТВИИ УДАРНОЙ ВОЛНЫ С ПЛАЗМОПАУЗОЙ 

ALFVÉN WAVES IN THE MAGNETOSPHERE 
GENERATED BY SHOCK WAVE / PLASMAPAUSE INTERACTION 
 
А.С. Леонович 
Институт солнечно-земной физики СО РАН, 
Иркутск, Россия, leon@iszf.irk.ru 
Цюган Цзун 
Институт космической физики и прикладных технологий, 
Пекинский университет, 
Пекин, Китай, qgzong@pku.edu.cn 
Д.А. Козлов 
Институт солнечно-земной физики СО РАН, 
Иркутск, Россия, kozlov-da@iszf.irk.ru 
Юнфу Ван 
Институт космической физики и прикладных технологий, 
Пекинский университет, 
Пекин, Китай, wyffrank@gmail.com 

A.S. Leonovich 
Institute of Solar-Terrestrial Physics SB RAS, 
Irkutsk, Russia, leon@iszf.irk.ru 
Quigang Zong 
Institute of Space Physics and Applied Technology, 
Peking University, 
Beijing, China, qgzong@pku.edu.cn 
D.A. Kozlov 
Institute of Solar-Terrestrial Physics SB RAS, 
Irkutsk, Russia, kozlov-da@iszf.irk.ru 
Yongfu Wang 
Institute of Space Physics and Applied Technology, 
Peking University, 
Beijing, China, wyffrank@gmail.com 

 
Аннотация. Исследованы альфвеновские волны, 
генерируемые в магнитосфере при прохождении 
межпланетной ударной волны. После прохождения 
были зарегистрированы колебания с дисперсией, 
типичной для альфвеновских волн. Чаще всего 
наблюдаются колебания с тороидальной поляризацией, пространственная структура которых хорошо 
описывается теорией резонанса магнитных силовых 
линий (FLR). Однако иногда после прохождения ударной волны наблюдаются колебания и с полоидальной 
поляризацией. Они не могли быть сгенерированы в 
результате FLR, но они также не могли быть вызваны 
и неустойчивостями потоков высокоэнергичных 
частиц, которые не наблюдались в это время. Мы 
обсуждаем альтернативную гипотезу, предполагающую, что резонансные альфвеновские волны могут 
возбуждаться вторичным источником — сильно локализованным импульсом быстрых магнитозвуковых 
волн, который генерируется в области контакта 
ударной волны с плазмопаузой. Спектр такого источника содержит гармоники колебаний, которые 
могут возбуждать как тороидальные, так и полоидальные резонансные альфвеновские волны. 
Ключевые слова: магнитосфера, плазмопаузы, 
ударный фронт, альфвеновские волны. 

Abstract. We study Alfvén waves generated in the 
magnetosphere during the passage of an interplanetary 
shock wave. After shock wave passage, the oscillations 
with typical Alfvén wave dispersion have been detected 
in spacecraft observations inside the magnetosphere. 
The most frequently observed oscillations are those with 
toroidal polarization; their spatial structure is described 
well by the field line resonance (FLR) theory. The oscillations with poloidal polarization are observed after 
shock wave passage as well. They cannot be generated 
by FLR and cannot result from instability of highenergy particle fluxes because no such fluxes were detected at that time. We discuss an alternative hypothesis 
suggesting that resonant Alfvén waves are excited by a 
secondary source: a highly localized pulse of fast magnetosonic waves, which is generated in the shock 
wave/plasmapause contact region. The spectrum of such 
a source contains oscillation harmonics capable of exciting both the toroidal and poloidal resonant Alfvén 
waves. 
Keywords: magnetosphere, plasmapause, shock 
front, Alfvén waves. 
 
 
 

 
INTRODUCTION 

A considerable part of geomagnetic pulsations observable in Earth’s magnetosphere are related to the 
generation mechanism known as “field line resonance” 
(FLR). In particular, resonant Alfvén oscillations can be 
generated by fast magnetosonic (FMS) wave pulses 
caused by interplanetary shock waves propagating in the 
magnetosphere [Allan et al., 1986]. 
This interpretation explains well the generation of 
Alfvén waves with toroidal polarization in the magneto
sphere [Leonovich, Mazur, 1989; Kozlov, 2010]. If the 
magnetospheric plasma in such a model is inhomogeneous in the meridional plane (along the magnetic field 
lines and across the magnetic shells), but homogeneous 
in the azimuthal direction, then all its oscillations can be 
regarded as an expansion in harmonics of the form 
~exp(imφ–iωt), where m=0, ±1, ±2, … is the azimuthal wave number, φ is the azimuthal angle, ω is the 
wave frequency.  
Toroidal Alfvén oscillations are excited by azimuthally large-scale FMS waves (with m~1). These FMS 

А.С. Леонович, Цюган Цзун, Д.А. Козлов, Юнфу Ван 
 
   A.S. Leonovich, Quigang Zong, D.A. Kozlov, Yongfu Wang 

12

waves can penetrate deep into the magnetosphere from 
the solar wind. Poloidal Alfvén waves are azimuthally 
small-scale (m≫1). The azimuthally small-scale FMS 
waves incident on the magnetosphere from the solar 
wind are reflected by the magnetopause, thus failing to 
penetrate into the magnetosphere [Leonovich, Mazur, 
2000; Cheremnykh et al., 2016]. The FMS waves that 
do penetrate into the magnetosphere are therefore believed to be likely to excite only toroidal Alfvén waves 
in it [Leonovich, 2001; Chelpanov et al., 2018]. 
After interplanetary shock wave passage, Alfvén 
waves with toroidal polarization are often observed inside the magnetosphere [Potapov, 2013]. They are generated by the field line resonance mechanism. A number 
of studies based on spacecraft observations have 
demonstrated, however, that Alfvén waves with poloidal 
polarization can also be excited inside the magnetosphere after shock wave passage [Zong et al., 2009; Liu 
et al., 2013]. Poloidal waves inside the magnetosphere 
are most often generated by unstable high-energy particle 
fluxes [Dai et al., 2013]. Sometimes (in 10–15 % of 
cases), however, Alfvén waves with both the toroidal 
and poloidal polarization are excited near the plasmapause, after an interplanetary shock wave front passes 
through the magnetosphere. In the preceding time interval, high-energy particle fluxes, which could be considered as a potential source of the poloidal waves, are 
absent from the observation region [Zong et al., 2017]. 
In this paper, we propose a new concept for the poloidal Alfvén wave generation in the magnetosphere by 
an interplanetary shock wave front. We suggest that the 
shock wave front penetrates the magnetosphere and 
interacts with the plasmapause. In their contact region, 
a fast magnetosonic wave packet arises which then generates Alfvén waves at resonance magnetic surfaces. We 
calculate the total field of Alfvén oscillations in the vicinity of the plasmapause using a cylindrical model of 
the magnetosphere. 
 
1. 
OBSERVATIONS 
AND POSSIBLE SCENARIO 

An example of such observations is shown in Figure 1. 
The measurements were carried out by the CLUSTER C3 
spacecraft, which was in the vicinity of the plasmapause 
at that time. Figure 1 contains 5 panels (a–e). The top (a) 
panel illustrates the behavior of the integral flux of highenergy (E>50 keV) electrons before and after the shock 
front passage. The behavior of the electric and magnetic 
components of the Alfvén oscillation field is presented on 
two panels (b, c): (b) for the poloidal (Br, Ea) and (c) for 
the toroidal (Ba, Er) modes. Panel (d) shows the behavior 
of the magnetic field z-component. The magnetic and 
electric fields are projected onto a local mean-fieldaligned (MFA) coordinate system, in which the parallel 
direction p is determined by the 15-min sliding averaged 
magnetic field, the azimuthal direction a is parallel to the 
cross product of the p and the spacecraft position vector, 
and the r completes the triad. Panel (e) of Figure 1 shows 
the cold plasma density deduced from the potential as 
measured by CLUSTER C1, C2, and C4. There was a 
gap in the C3 spacecraft potential data, but all the four 
spacecraft are quite close to each other in this case. We 
use the method proposed by Moullard et al. [2002] to cal- 

 

Figure 1. CLUSTER C3 measurements of ULF waves and 
energetic electron flux perturbations induced by an interplanetary shock on November 7, 2004: the integral flux of energetic 
electrons (E>50 keV) measured by RAPID onboard C3 (a); 
the toroidal mode wave magnetic field Ba and electric field Er 
(b); the poloidal mode wave magnetic field Br and electric 
field Ea (c); the magnetic field Bz component from C3 (d); the 
cold plasma density Ne deduced from spacecraft potential 
measured by CLUSTER C1, C2, and C4 (e). The position in 
GSM, L value, invariant latitude (ILat) and magnetic local 
time (MLT) for C3 are shown at the bottom. The vertical 
dashed line shows the arrival time of the interplanetary shock 

culate the density from the spacecraft potential. We can 
see that the cold plasma density is ~20 cm–3, the typical 
value near the plasmapause. 
It is evident from Figure 1 that after the shock front 
passage both modes of Alfvén oscillations are excited: 
poloidal and toroidal. After that, the poloidal component 
amplitude of the oscillation field decays rather quickly, 
while the toroidal component amplitude remains almost 
unchanged. At the same time, the high-energy electron 
flux begins to increase. Zong et al. [2017] suggested 
that poloidal Alfvén waves interact with the plasma 
electrons, transferring their energy to them. 
The question remains as to the source of the poloidal 
Alfvén waves themselves. We suggest the following 
generation scenario for such poloidal Alfvén oscillations 
generated by shock wave passage through the magnetosphere. When the shock wave front interacts with the 
plasmapause, a localized perturbation arises in their 
intersection region. A narrowly localized FMS wave 
packet contains harmonics capable of effectively exciting both toroidal and poloidal Alfvén waves. Using the 
cylindrical model of the magnetosphere, we calculate 
the field of Alfvén oscillations generated in the magnetosphere by such a secondary source and determine sectors, where the poloidal magnetic field component dominates in the generated Alfvén oscillations. 
 
2. 
MEDIUM MODEL 

We consider the generation of Alfvén waves by an 
FMS wave packet in the near-equatorial region of the real