3rd ISEE Symposium

ISEE, Nagoya University, Japan
March 8-12, 2021

ABSTRACT BOOK

Chorus waves in the outer radiation belt driven by recurrent solar wind structures
L. R. Alves (INPE), G. B. D. da Silva (INPE), L. A. da Silva (INPE; China-Brazil Joint Lab Space
Weather), Vitor M. Souza (INPE), O. Agapitov (University of California;University of Kyiv), Luis
E. A. Vieira (INPE), M. Virginia Alves (INPE), Paulo R. Jauer (INPE), José P. Marchezi (INPE),
Claudia Medeiros (INPE), David G. Sibeck (NASA Goddard), Shrikanth G. Kanekal (NASA
Goddard), J. Bernard Blake (The Aerospace Corporation), Craig Kletzing (University of Iowa),
Daniel Baker (University of Colorado)

Coronal Holes (CH) are predominant at the solar disk through the descending phase of
the solar cycle. They can persist in the solar disk for several rotations, and thus be often a sourceof high-speed solar wind stream (HSS), which leads to a corotating interaction region (CIR)
generation. At the magnetosphere, the arrival of CIR-HSS increases magnetospheric convection,
triggers the onset of substorms and also transport Alfvénic fluctuations through magnetosphere.
Our results show that these three mechanisms, associated to the source (few keV) and seed (10sto 100s of keV) particles injection may drive changes in the outer radiation belts. In this paper,
we use Van Allen Probes data to investigate the chain of significant magnetospheric events
related to the arrival of CIR followed by HSS, throughout seven recurrences of the same CH,
observed from November 2017 to May 2018. Our results show that the VLF wave activity andchanges in the electron flux parameters occurs in three main periods. First, the arrival of a CIR
causes magnetopause shadowing, enhancement of Alfvénic fluctuations, and oblique Chorus
waves. These events are related to initial relativistic electron flux dropout observed in several
events. Then, as the following HSS comes right after, seed injections are observed simultaneously
to the increase of the magnetospheric disturbance and the persistence of raised solar wind speed.
The conjunction of these latter conditions favored the occurrence of whistler mode chorus waves
to cause acceleration. Otherwise, in the absence of seed injections, the relativistic outer radiation
belt dropout is observed.

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First results from the ELFIN mission and equatorial spacecraft conjunctions.
V. Angelopoulos, E. Tsai, C. Wilkins, R. Caron, A. Runov, X. Zhang, A. Artemyev and the ELFIN
Team, UCLAThe Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving
option (ELFIN-STAR, or ELFIN*) mission, comprised of two identical 3U+ CubeSats, waslaunched in September 2018 to explore the mechanisms responsible for relativistic electron loss
during magnetic storms. All instruments and spacecraft are functioning nominally providing atleast one complete scan of the radiation belt L-shells once per orbit (90 min period) from eachsatellite. Pitch-angle resolved energy spectra of electrons between 50-5000keV are measured at±22.5deg resolution clearly separating trapped, precipitating and backscattered electrons.
Satellite separations from one to tens of minutes along-track enable resolution of spatial andtemporal variations to determine the latitudinal width and temporal evolution of the
precipitation. First results include: A. There is a statistically significant up-going population thatis present both at quiet and active times, likely due to atmospheric scattering. We explain its
dependence on activity, local time, trapped flux and precipitation level. B. There are many cases
where >1MeV particles are observed to have been scattered into the loss-cone at fractions greaterthan at lower energies – these are candidates for EMIC wave scattering. Simultaneous

measurements from equatorial satellites support this hypothesis. C. There are numerous

observations of intense precipitation in the 50-500keV range that qualify for whistler modechorus scattering – these too are consistent with equatorial observations. D. There are routine
nightside observations of broad precipitation across all energies that exhibit energy-latitude
dispersion. These are candidates for field-line curvature scattering. They can be used to adjust
magnetic field models for mapping precipitation boundaries and field-aligned currents to theirdrivers in near-Earth space, and compare those with equatorial spacecraft measurements. Thevery low noise background and high count rates allow for future operational modifications. Thoseare expected to extend observations to the inner radiation belt, and to improve the pitch-angle
resolution of the measurements to <34deg allowing, after some modeling, for better resolution of
the loss-cone gradient.

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Acceleration and loss of the outer radiation belt electrons and auroral processes
E.E.Antonova(1,2), M.V. Stepanova(3), Ovchinnikov(1), N.A. Sotnikov(1), M.O. Riazantseva(2), I.P.
Kirpichev(2), V.G. Vorobjev(4), O.I. Yagodkina(4), V.A. Pinto(5)(1) Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University. Moscow, Russia(2)Space Research Institute RAS, Moscow, Russia(3)Physics Department, Science Faculty, Universidad de Santiago de Chile, Chile(4)Polar Geophysical Institute, Apatity, Murmansk Region, Russia(5)Institute for the Study of Earth, Oceans, and Space, University of New Hampshire Durham,
NH, USA

Outer radiation belt (ORB) relativistic electron fluxes dropouts during storm main
phases, around 45%–50% after storms enhancements, 20%–25% after storms depletion, and
25%–28% almost unchanged continue to be unsolved problems in spite of many researches
including the realization of RBSP/Van Allen mission. Ordinarily discussed mechanisms ofparticle precipitation and magnetopause shadowing can not explain the existence of magnetic
storms when particle fluxes after storm restore till the level of the fluxes before the storm.
Popular “quasilinear” models cannot explain time intervals of great increases of ORB fluxes nearto substorm time intervals. Such situation is explained by the underestimation of the role ofauroral processes in the ORB dynamics. We summarize the latest findings in the ORB andauroral processes connections including outer part of ORB intersection with the region of theauroral oval mapping to the equatorial plane, auroral oval motion to lover latitudes during
magnetic storms, great magnetic field variations at the equatorial plane during storms and anumber of other effects. The dominant role of adiabatic mechanism in the ORB dynamics duringstorm main and recovery phases is demonstrated. The ORB dynamics prediction and plans of
future works including analysis of data of auroral missions are discussed.

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Perpendicular heating of low-energy ions by fast magnetosonic waves observed by Arase (ERG)
satellite
K. Asamura (ISAS/JAXA), Y. Miyoshi(ISEE, Nagoya U.), M. Shoji (ISEE, Nagoya U.), Y. Kasaba(Tohoku U.), Y. Kasahara (Kanazawa U.), and A. Matsuoka (Kyoto U.)

Fast magnetosonic (MS) waves are commonly observed in the equatorial region of theinner magnetosphere. Past numerical simulations show MS waves can accelerate low-energy ionsthrough cyclotron resonance, although the observational evidence is still unclear. Arase (ERG)
satellite found events of perpendicular heating of cold ions simultaneously with plasma wave
activities of the MS waves. We have applied the WPIA (wave-particle interaction analysis)
method to the selected ion heating event with the MS waves. The results show that the MS waves
accelerate the low-energy (< ~10keV) ions with pitch angles near 90 degrees. We also found theseions give their energy to EMIC waves which appears just below the local proton cyclotron
frequency. Since MS waves are considered to be generated by the ring distribution of ions, thisanalysis indicates energy transfer from higher-energy ions to the lower-energy ions in the innermagnetosphere.

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Measurements of geomagnetic pulsations and aurora at Zhigansk and VLF registration at
Maimaga as part of PWING project
Baishev D.G. (SHICRA SB RAS, YaSC SB RAS) Russia), and Shiokawa K. (ISEE, Nagoya
University)
PWING network consist of eight stations at subauroral latitudes (~ 60° geomagnetic
latitude) in the northern hemisphere, distributed longitudinally in Canada, Iceland, Finland,
Russia, and Alaska to obtain the longitudinal distribution of plasmas and waves in the innermagnetosphere. PWING has been developed as a part of the ERG (Arase)-ground coordinatedobservation network. SHICRA SB RAS has long-term and productive scientific relationships withISEE (former STEL), Nagoya University. In the framework of PWING project Nagoya University
provided SHICRA SB RAS scientific equipment, described in [Shiokawa et al., EPS, 2017, DOI
10.1186/s40623-017-0745-9]. At present time, SHICRA SB RAS operate all-sky airglow camera,
64-Hz sampling induction magnetometer and broad-beam riometer at Zhigansk (66.8 N, 123.4
E), and 40-kHz sampling VLF receiver with loop antenna and electronic recorder of low-frequency
electromagnetic radio waves at Maimaga (63.1 N, 129.6 E). We present some results on
interaction of electromagnetic electron and ion-cyclotron waves and with particles in the innermagnetosphere in the sector which manifesting in generation of discrete low-frequency signals
in the Earth’s magnetosphere, such as chorus in VLF emissions, “pearls” in the Pc1 range, andalso irregular pulsations of diminishing period (IPDP).

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Declining solar activity trends during solar cycles 25 and 26
A.Bhargawa and A.K. Singh

We have used the already observed data of solar parameters viz. sunspot numbers, F10.7 cm
index and Lyman alpha index recorded for last seventy years (1947–2017).We have applied the
Hodrick Prescott filtering method to bifurcate each time series into cyclic and trend parts. The
cyclic part of each time series was used to analyse the persistence while the trend part was used
to obtain the input data for the study of future predictions. Further, the cyclic component of eachparameter was analysed by using the rescaled range analysis and the value of Hurst exponent
was obtained for sunspot numbers, F10.7 cm index and Lyman alpha index as 0.90, 0.93 and 0.96
respectively. By using the simplex projection analysis on the values of amplitude and phase of
the trend component of each time series, we have reconstructed the future time series
representing solar cycles 25 and 26. When extrapolated further in time, the reconstructed series
provided the maximum values of sunspot numbers as 89 ± 9 and 78 ± 7; maximum values of F10.7
cm index were 124 ± 11 and 118 ± 9 and Lyman alpha index were 4.61±0.08 and 4.41±0.08
respectively for solar cycles 25 and 26. In our analysis we have found that the solar cycle 25 will
start in the year 2021 (January) and will last till 2031 (February) with its maxima in year 2024
(February) while the solar cycle 26 will start in the year 2031 (March) with its maxima in 2036
(June) and will last till the year 2041 (February).

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Fermi acceleration in Saturn magnetosheath at corotating magnetic reconnection site
Tusharkumar Bhatt1, Rajmal Jain2, Dipali Burud1, Arunkumar Awasthi3, Sneha Chaudhari1,
Andrew Coates4, Dhiren Kataria4
1. Kadi Sarva Vishwavidyalaya, Gandhingar, Gujarat, India
2. Physical Research Laboratory, Navrangpura, Ahmedabad – 380009, India
3. CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary
Sciences, University of Science and Technology of China, Hefei230026, People’s Republic ofChina
4 .Mullard Space Science Laboratory, University College London, Holmbury ST Mary,
Dorking, Surrey, RH 56 NT, UK

We found field aligned electrons (FAE) and anti-parallel electrons (APE) in the ion andelectron diffusion region at corotating magnetic reconnection site in Saturn magnetosphere at
the magnetosheath. The FAE can reach closer to the planet with fermi accelerated electrons while
APE confine at the equator give betatron acceleration. The betatron acceleration is not expected
because total magnetic field value is decreased from 3.45 to 1.11 nT. We found heated electron
peaks which confirms fermi acceleration between 49.3Rs to 48.7Rs at 0.4˚ latitude. The electron
density was between 0.062m^-3 to 0.549m^-3 and temperature was between 10.87eV to 25.55eV.

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ULF wave observations in the ionosphere using the EKB coherent radar
M.A. Chelpanov, O.V. Mager (ISTP)

Ultra low frequency (ULF) waves can be efficiently observed at the ionosphere, where
they map from the magnetosphere. Radars provide steady opportunity to study their structure,
localization, and relations with other phenomena. A midlatitude coherent decameter radar
similar to SuperDARN radars was launched in 2012 near Ekaterinburg (EKB), Russia. During
the experiment conducted in 2013–2015 its three adjacent beams were scanning the ionosphereat high time resolution mode, providing 18 s cadence at each beam. These three beams are
directed approximately towards the magnetic pole. Therefore, they register the poloidal
component of ULF waves. A review of several interesting events studied using the data from theradar are presented. (1) A number of waves with frequencies considerably lower than theappropriate field line resonance (FLR) frequencies were registered. The FLR frequencies for eachcase were inferred from spacecraft data on particle density and magnetic field. It is assumed thatat least a part of the waves observed with the radar should be identified with the drift
compressional mode, whose frequency can be lower than Alfvén frequency. (2) A wave with asynchronous decrease both in frequency and azimuthal number m was observed. Such linear
dependence of frequency on m, together with sub-Alfvénic frequency and westward propagation
is a characteristic of the drift compressional mode. (3) A case of merging of two waves was shown.
Apparently, they represent the drift compressional and Alfvén modes, which can merge at somecritical value of azimuthal wave number m. (4) A wave was registered at the radar and Van Allen
Probe spacecraft simultaneously. It was poloidal and diamagnetic (magnetic and plasma pressure
oscillations are in anti-phase). Its frequency was lower than the FLR fundamental frequency.
Therefore, it was some kind of compressional mode, apparently the drift compressional one.
The study was supported by the Russian Foundation for Basic Research grant 20-55-53009. The
performance of the EKB radar was supported by the Program for Fundamental Research of theRussian Academies of Sciences for 2013–2020 (project II.12.2).

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Detection of auroral kilometer radiation from the northern and southern hemispheres using the
ERG satellite
A. A.Chernyshov, M. M. Mogilevsky, D. V. Chugunin (IKI RAN), V. I. Kolpak (IKI RAN, HSE),
A. Kumamoto (Tohoku University), Y. Kasahara (Kanazawa University)

Auroral Kilometric Radiation (AKR) signals from sources in the auroral regions of thenorthern and southern hemispheres are simultaneously recorded and analyzed using the data of
the ERG satellite. Initially, type III solar radio bursts are applied as a calibration signal and it
is shown that there is no polarization of this signal that is in good agreement with previous
results and indicates the correct calculation of the polarization parameter on board the ERG
satellite. In our study, two sources of AKR spaced apart in frequency are distinguished. Most
likely, this is due to spatial-frequency filtering of sources separated in space. It is noted that there
are differences in the AKR generation in the northern and southern hemispheres. It is shownthat either northern or southern sources of AKR prevail at different times.

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Quantifying the drivers of electron loss from the Earth’s radiation belts
Seth Claudepierre (UCLA/Aerospace Corp), Qianli Ma (Boston U/UCLA), Jacob Bortnik (UCLA)

We use observations from the Van Allen Probes, together with electron lifetime
calculations from quasilinear diffusion modeling, to identify and quantify the drivers of electron
precipitation from the Earths inner radiation belt and slot region. We build on our recent workthat examined the role of ground-based Very Low Frequency (VLF) transmitter waves inprecipitating electrons from the inner belt, which was demonstrated to exhibit a bifurcatedstructure (two-belt inner zone) due to the action of the VLF transmitter waves. We present new
results that explicitly account for the role of lightning-generated whistler (LGW) waves in theelectron lifetime calculations, using a statistical database of LGW waves recently obtained fromthe Van Allen Probes. In addition to these calculations of electron precipitation via quasilinear
wave-particle interactions, we also consider a revised formulation of Coulomb scattering andexamine the role of Coulomb energy drag in reducing the electron lifetimes. The theoretical
calculations and modeling results are compared with observed electron decay rates to identify
the physical processes most relevant for radiation belt electron precipitation.

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Athabasca University, PWING, and Arase
M. Connors (Athabasca University and University of Calgary)

Athabasca University’s cooperation with Japanese scientists began twenty years ago
with the visit of the late Tsuruda-sensei. He taught the value of patience, as a first visit under
two full weeks of cloudy skies led to a second one with amazing aurora viewing. In 2004,
Athabasca began cooperation with the late Hayashi-sensei to maintain the STEP Polar Network,some of whose stations are still operating, and even enhanced. In 2005, Nagoya University
installed equipment at the original Athabasca University Geophysical Observatory (now anequipment test site). Due to early successes, funding was obtained a decade ago for the GeoSpace
Observatory (AUGSO) in a very dark site, and which opened with a visit by a Nagoya University
team in early 2012. This talk will review work done, mainly on subauroral phenomena including
detached proton auroras, SAR Arcs, and STEVE. The focus will be on observations withcomplementary instruments, including those of the AUTUMN East-West magnetic array. The
most recent AUGSO thrust is in time-domain magnetotellurics, in which direct measurements of
induced electric fields is relevant to space weather studies. Athabasca University’s MAMA-MIA
project will link geoelectric measurements and proton auroras, and AUGSO will be a site in the
University of Calgary’s large TREx observatory network project covering much of western
Canada.

Page | 11SafeSpace: Designing Radiation Belt Environmental Indicators for the Safety of Space Assets
Ioannis A. Daglis (National &amp; Kapodistrian University of Athens, Athens, Greece),
Sébastien Bourdarie (ONERA/DESP, Toulouse, France), Stefaan Poedts (Centre for Plasma
Astrophysics - KU Leuven, Leuven, Belgium, Ondrej Santolik (Institute of Atmospheric Physics,
Prague, Czech Republic, Fabien Darrouzet (Belgian Institute for Space Aeronomy, Brussels,
Belgium), Juan Cueto Rodriguez (Thales Alenia Space España , Madrid, Spain), Benoit
Lavraud(CNRS, Toulouse, France), Ingmar Sandberg (SPARC - Space Applications &amp;
Research Consultancy, Athens, Greece)

The SafeSpace project aims at advancing space weather nowcasting and forecasting
capabilities and, consequently, at contributing to the safety of space assets through the transitionof powerful tools from research to operations (R2O). This will be achieved through the synergy offive well established space weather models (CNRS/CDPP solar disturbance propagation tool,
KULeuven EUHFORIA CME evolution model, ONERA Neural Network tool, IASB plasmaspheremodel and ONERA Salammbô radiation belts code), which cover the whole Sun – interplanetary
space – Earth’s magnetosphere chain. The combined use of these models will enable the delivery
of a sophisticated model of the Van Allen electron belt and of a prototype space weather serviceof tailored particle radiation indicators. Moreover, it will enable forecast capabilities with a target
lead time of 2 to 4 days, which is a tremendous advance from current forecasts that are limited
to lead times of a few hours. SafeSpace will improve radiation belt modelling through theincorporation into the Salammbô model of magnetospheric processes and parameters of criticalimportance to radiation belt dynamics. Furthermore, solar and interplanetary conditions will be
used as initial conditions to drive the advanced radiation belt model and to provide the link tothe solar origin and the interplanetary drivers of space weather. This approach will culminate ina prototype early warning system for detrimental space weather events, which will include
indicators of particle radiation of use to space industry and spacecraft operators. Indicator values
will be generated by the advanced radiation belt model and the performance of the prototype
service will be evaluated in collaboration with space industry stakeholders. The work leading tothis paper has received funding from the European Union’s Horizon 2020 research andinnovation programme under grant agreement No 870437 for the SafeSpace (Radiation Belt
Environmental Indicators for the Safety of Space Assets) project.

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Conjugate ground-spacecraft observations of VLF emissions
A.Demekhov, E.E. Titova, A.A. Lubchich, A.S. Nikitenko (Polar Geophysical Institute), J.
Manninen (Sodankula Geophysical Observatory), and D.L. Pasmanik (Institute of Applied
Physics)

A review of recent results on conjugate ground-spacecraft observations of various types
of VLF emissions such as quasi-periodic and chorus emissions will be given. For quasi-periodic
emission, it will be shown that quasi-parallel propagation with respect to the geomagnetic field
and the appopriate Poynting flux direction away from the equator are not sufficient to infer thelocation of a spacecraft within a generation region of such signals. Using the whistler mode
growth rate calculations serve as important tool for identifying the spacecraft passage in aprobable generation region. For chorus emissions we demonstrate a persistence of a discreteelement structure for a two-hop pass from a generation region to the ground and back to themagnetisphere after the reflection from the ionosphere or from the ground. In all cases the useof propagation properties of VLF emissions detected on the ground can greatly help in resolving
ambiguities with respect to the possible location of the signal generation region. Examples ofsimulations of related wave-particle interactions will be given.

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A theoretical study of mirror-point altitude variability due to geomagnetic field variations
Ana G. Elias (1,2), Bruno S. Zossi (1,2), Alvaro R. Gutierrez Falcon (3) and Hagay Amit (4)(1) Laboratorio de Ionosfera, Atmosfera Neutra y Magnetosfera - LIANM, Facultad de Ciencias
Exactas y Tecnologia, Universidad Nacional de Tucuman, Av. Independencia 1800, 4000 Tucumán,
Argentina(2) INFINOA, CONICET-UNT, 4000 Tucuman Argentina(3) Departamento de Física, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de
Tucumán, Av. Independencia 1800, 4000 Tucuman, Argentina(4) CNRS, Universite de Nantes, Nantes Atlantiques Universites, Laboratoire de Planetologie etde Geodynamique, Nantes, France

The Earth’s intrinsic magnetic field has been weakening at ∼5% per century from at least1840 mostly determined by the decrease in the dipolar magnetic moment component. This may
point out an undergoing reversal or excursion, or maybe the possibility of a recovery without any
extreme event. In any case, the global field intensity will very probably continue to decrease in
the near future with a consequent weakening of our planet’s magnetic shield capacity. In thecurrent dipole like geomagnetic field, where the field intensity gets stronger with increasing
magnetic latitude, there exist points in the northern and southern hemisphere, called magnetic
mirror points, where charged particles traveling along a field line bounce between them. This
motion is one of the three cyclic motions of trapped particles in the magnetosphere. The mirror
points altitude depends directly on the magnetic moment, which means that a magnetic decrease
may induce an altitude lowering eventually reaching the atmosphere. A theoretical estimate ofmagnetic mirror points lowering rate due to the current geomagnetic field decrease is estimatedand compared to the shrinking of the upper atmosphere due to greenhouse gases increase during
the last 120 years.

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Electromagnetic ion cyclotron (EMIC) waves in Earth’s magnetosphere: Recent satellite andground-based observations and some future prospects
M. J. Engebretson (Augsburg University)

Observations from the Van Allen Probe, Magnetospheric Multiscale, and ERG spacecraft
missions, often complemented by ground-based observations, have spurred a large number ofstudies of waves in the Pc1-2 band, including especially electromagnetic ion cyclotron (EMIC)
waves, and of their impact on ultrarelativistic radiation belt electrons. This presentation will
review several recent studies of the origins, properties, and impacts of these waves, and will
highlight several continuing issues and new techniques that may attract increased attention in
the next few years.

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A comparison of upper atmospheric Joule heating resulting from CMEs and HSSs using
SWMF/BATS-R-US model
P. Erdemir*, Z. Kaymaz*, E.C. Kalafatoglu Eyiguler*, and L. Rastaeter***Istanbul Technical University, Faculty of Aeronautics and Astronautics, Department ofMeteorology, Maslak, 34450, İstanbul, Turkey**NASA/GSFC, Space Weather Laboratory, CCMC, Greenbelt, MD 20771, Maryland, US

Upper atmospheric Joule heating is an indication of the magnetospheric energy andmomentum downloaded into the upper atmosphere in the ionospheric heights during themagnetospheric substorms.

Both coronal mass ejections (CMEs) and high speed streams (HSSs)

are shown to cause magnetospheric substorms.

They have distinct characteristics in the solar

wind.

Therefore, the response of the magnetosphere is expected to be different during these

events.

In this study, we investigate the Joule heating resulting from these two solar

disturbances.

We chose two geomagnetic storms/magnetospheric substorm events, one that

corresponds to a CME and the other one to HSS, and used SWMF/BATS-R-US MHD model toevaluate the Joule heating in the upper atmosphere.

We determined the Joule heating rates

according to the substorm and storm phases. We showed that the Joule heating rates are higher
during the CME driven storm/substorm when compared to the HSS driven storm/substorm.
Also we found that the Joule heating rate is higher during the main phase of the storm in bothcases.

For the events we studied, we also obtained that Joule heating rate is higher during the

expansion phase of the HSS driven substorm. We quantify the Joule heating in each case. We
will present and discuss the results from our preliminary search in this meeting.

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Modeling the Inner Magnetosphere with the CIMI Model
Mei-Ching Fok (NASA GSFC), Alex Glocer (NASA GSFC), Jonathan Krall (NRL), Joe Huba
(Syntek Technologies), Naomi Maruyama (university of Colorado), and Cristian Ferradas(Catholic University of America)

A Comprehensive Inner Magnetosphere-Ionosphere (CIMI) model was developed to
study the dynamic variations of the radiation belts, ring current, and plasmasphere as well as
the interactions between these populations and with the ionosphere. Recently, the CIMI model
was coupled with two well established models: SAMI3 (Sami3 is Also a Model of the Ionosphere)
and IPE (Ionosphere-Plasmasphere-Electrodynamics) models. Ring current heating to theplasmasphere is calculated in the CIMI model. This heating is added to the electron temperatureequation in SAMI3 in a form of ring current heating function. With this additional heating, a cold(<1 eV) oxygen ion outflow is produced, with O+ density and location similar to observations of
the so-called “oxygen torus”. On the other hand, the electric field calculated in CIMI is used todrive the plasma convection in the IPE model during the storm on 7-9 September 2017. The
severe erosion of the plasmasphere observed by the Van Allen Probes and ERG satellites during
the storm is reproduced by the IPE model. The strongest erosion observed on the dawn side canbe explained by ring current shielding and day-night asymmetry in ionospheric conductance thatare accounted for in the CIMI model. The CIMI model and it predecessors have been coupled with
global MHD models for more than two decades, but just recently the core plasma simulated in
the CIMI model is treated as an additional fluid in the BATSRUS MHD model. The inclusion of
the plasmasphere is found to have a system-wide impact. Specifically, when the plasmaspheredrainage plume reaches the magnetopause, it can reduce the reconnection rate, suppress
ionospheric outflow and change its composition, change the composition in the magnetosphere,
and reduce the ring current intensity. We are working toward to a comprehensive modeling of
the inner magnetosphere considering all the important physical processes and interactions.

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Forecast of energetic electron flux variations of the outer belt using the machine learning
S. Fukuoka(1), Y. Miyoshi(1), S. Kurita(2), I. Park(1), T. Hori(1), S. Imajo(1), T. Mitani(3), T. Takashima(3),N. Higashio(3), I. Shinohara (3), A. Matsuoka(2), D. Shiota(4)(1)ISEE, Nagoya University(2)Kyoto University(3)JAXA(4)NICTThe relativistic/sub-relativistic electron flux variations often cause serious damage on
the satellite operations through the dielectric charging. In order to forecast flux variations ofthese electrons, various forecast methods based on the physical based simulation and empiricalmodeling have been developed. For the physics-based simulation, the SUSANOO that operates
a code-coupling simulation of heliosphere and radiation belt provides MeV electron flux
variations for the next couple of days. For the empirical modeling, the linear prediction filter andthe auto-regressive moving average are popular methods, which have been used for the forecastof MeV electrons at geosynchronous Earth orbit (GEO). Recently, the machine learningtechniques have widely been used for the space weather forecast, for example, ionosphericvariations, the flare prediction, etc. In this study, we have developed the forecast system of
relativistic/sub-relativistic electron flux variations based on long short-term memory recurrent
neural network (LSTM-RNN). As the training data, we use the solar wind data and energetic
electron data observed by Arase/HEP, XEP instruments at different L-shells of the outer belt.
Our developed network provides time variations of the energetic electron flux around L=4,5,6
using the solar wind data as an input parameter. In this presentation, we will present the initial
results of our developed network and discuss effective solar wind parameters to reproduce theobserved flux variations at different L-shells.

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Driving parameters for energetic electron fluxes variation in outer radiation belt
B.Geletaw, M.Negussie, G.D.Reeves, S.Wing

The Earth’s outer radiation belt is highly dynamic and the variations of energetic
electron population in the region depends on solar wind and interplanetary magnetic field (IMF)
parameters. Recently, observations of Van Allen probes have used to analyze the electron flux
variations; however, the causes for different response to electron fluxes are still unclear. The
main objective of this work is to analyze the causal relationship of solar wind and IMF
parameters on the variation of energetic electron fluxes in outer radiation belt using information
theory approach. We attempt to characterize the influence and timing of the solar wind and IMF
parameter activities on the radiation belt environment based on time-shifted cross-correlation,
mutual information and transfer entropy tools. We have used Van Allen probes energetic electron
flux data with energy channels of 3.4, 4.2, 5.2 and 6.3MeV in the period from 01 January 2017 to
31 December 2018. Our analysis applied for three ranges of L-shell which are ∼ 4.0 (3.95 ≤ L<4.05), ∼ 4.5 (4.45 ≤ L<4.55) and ∼ 5.0 (4.95 ≤ L <5.05). The results indicate that the informationtransfer from solar wind and IMF parameters to energetic electron flux in outer radiation belt isdependent on ranges of L-shell, type of driving parameter and energy of electrons in outerradiation belt. We ranked the driving parameters based on transfer information level whilecausing energetic electron flux variation. The results also illustrate that solar wind velocity is
the dominant driving parameter for the variation of energetic electron flux. Moreover, the time
shifted dependency analysis of the variables confirmed that the lag time is decreasing as L-shellincreasing. For instance in the case of Vsw(t) and Je(t + τ) peak correlation functions, we haveobserved that τmax = +7 days for L-shell of 4.95 ≤ L <5.05 and τmax = +10 days for 4.45 ≤ L<4.55. Such dependency analysis can help to select the model parameters that influence thevariation of energetic electron fluxes and to improve the existed models of the dynamical system.

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Multi-event conjugate measurements of the SAR arcs detachments using all-sky camera at
Athabasca, Canada and DMSP satellites (F13-F19)
A. Gololobov (NEFU, Yakutsk), K. Shiokawa (ISEE, Nagoya), D. Baishev (SICRA SBRAS,
Yakutsk), Y. Inaba (ISEE, Nagoya), Y. Otsuka (ISEE, Nagoya) and M. Connors (Athabasca
University, Alberta)

Stable auroral red (SAR) arcs are one of the phenomena of atmospheric emission at 630.0
nm associated with magnetosphere-ionosphere coupling.

It is considered that SAR arc emission

is driven by energy transported from the ring current into the ionosphere at subauroral latitudes
during magnetic storms. The energy deposited in the thermal plasma at high altitudes istransported into the subauroral ionosphere along geomagnetic field lines as a heat flow or lowenergy particles flux (few eV) and leads to electron temperature elevation up to and sometimes
in excess of 3000 K at a height of about 400 km. These temperatures are required for observable
630.0 nm emissions. In the present work we report the first multi-event conjugate measurementsof SAR arc detachment from the auroral oval using DMSP satellites (F13-F19) and ground-based
all-sky imager at Athabasca (Canada) (54.6o W, 246.36o Е, MLAT=61.5o, MLON=308.3o, L=4.4).
We found 86 events of SAR arc detachment conjunctions in the northern hemisphere and 98
events of conjugate pass in the opposite hemisphere from 2006 to 2018. Measurement aboard
DMSP satellites shows that detached SAR arcs are usually associated with electron temperature(Te) enhancement and electron density (ne) trough. We also found that SAR arc detachment
sometimes co-located with localized westward or eastward drift which may be associated with
Subauroral Ion Drift (SAID) or abnormal SAID (ASAID) events, respectively. The Te measured
by DMSP associated with detached SAR arcs positively correlates with F10.7 solar activity index.
The measured values of ne, Te and horizontal ion drift velocity (Vh) have a better correlation
with the AE and PCN index than with the SYM-H index, indicating that SAR arc detachment
related primarily to substorms and solar wind - magnetosphere coupling. The measurements
aboard DMSP satellites in the conjugate point in the southern hemisphere corroborate thepossibility of association of detached SAR arc with localized westward or eastward horizontal
drifts. We speculate that SAR arc detachment may be related to the energization of the ring
current during the substorm process and following energy transfer from the ring current throughthe field lines downward to the ionosphere.

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Atmospheric physics/ external Geophysic
F.O. Grodji (Unuversity of Felix Houphouët Boigny), V.Doumbia (UFHB), K. Boka (UFHB), C.
Amory-Mazaudier (ICTP), Y. Cohen (IPGP), R.Fleury(CNRS)The Equatorial Electrojet (EEJ) is a day-side eastward electric current that flows along
the geomagnetic dip equator in the E-layer the ionosphere at 105 km altitude. The EEJ was
discovered at Huancayo (Peru) in 1922, where the amplitude of the daily regular variation of thegeomagnetic field horizontal component was found to be 2 to 2.5 higher than that observed at
mid-latitudes. Most of the spatial and temporal characteristics of the EEJ, such as its half-width,
position of the center, the current intensity at the center, etc., are usually estimated from its
magnetic effects observed on ground and on board low altitude orbiting satellites. However, theparameters resulting from the electrodynamics processes of the low latitude ionosphere cannot
be estimated from geomagnetic field data. In the present work, the electrodynamics parameters(Ey, EP, JP1, JH2 JEEJ) was estimated from a semi-empirical approach. This method consistedof using the ionosonde data along with models such as the IRI, IGRF, NHPC_421, SAO-Explorer
and MSIS-E-90. In addition, by integrating JEEJ in height, the peak current density (I0) at theEEJ center was estimated. The results were compared with the peak current density (I0) inferredfrom magnetic data in order to evaluate the electrodynamic consistency of the method and theestimated values. Then, we examine the longitude dependence of the equatorial electrojet (EEJ).
In order to understand the background physical process responsible of remarkable feature is the“wave-four” structure of the EEJ longitude profile, we have examined the influence of thegeomagnetic-field intensity and that of migrating thermospheric tides. Then, By means ofsimulation through the National Center for Atmospheric Research (NCAR)’s ThermosphereIonosphere Electrodynamics General Circulation Model (TIEGCM), we have shown that the
combination of the longitudinal inequalities of the main geomagnetic-field intensity and the tidalwave longitudinal structures is necessary to produce the wave-four structure of the EEJ
longitude profile. Finally, we have shown the seasonal variability of the EEJ longitude profiles,
which may be controlled by the seasonal behaviors of the wind system in the thermosphere.

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Geomagnetic Field Variations During Quiet and Disturbed Days Over Iznik, Turkey
E. Gülay, Z. Kaymaz, and E.C. Kalafatoğlu Eyigüler (Istanbul Technical University)

In this study, we investigate the possible effects of the geomagnetic activity on themagnetic field measured on the ground at Iznik geomagnetic station (40.5°N, 29.72°E) in Turkey.
We select two magnetically active days using Dst and AE magnetic indices. We determine thegeomagnetic field deviations occurring during these magnetic storms from the backgroundgeomagnetic field obtained during magnetically quiet days. We evaluate the variations according
to the storm/substorm phases and quantify the differences with respect to the quiet days. In
addition, we study the variations in the time derivatives of the geomagnetic field during theactive and quiet times. Time derivatives of the magnetic field are associated with the electricfield through Maxwell equations, which in turn are related to the currents. We infer thegeomagnetically induced currents (GICs) using these time derivatives and emphasize on the
differences between the active and quiet days. Our results will bring insights in magnetosphereionosphere-ground coupling at mid-latitudes. We will present our preliminary results and discuss
our findings in the context of the available literature.

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Long term features of geomagnetically trapped particles
Alvaro R. Gutierrez Falcon(1), Bruno S. Zossi(2,3), Hagay Amit(4) and Ana G. Elias(2,3)(1) Departamento de Fisica, Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de
Tucumán, Av. Independencia 1800, 4000 Tucuman, Argentina(2) Laboratorio de Ionosfera, Atmosfera Neutra y Magnetosfera - LIANM, Facultad de Ciencias
Exactas y Tecnología, Universidad Nacional de Tucuman, Av. Independencia 1800, 4000 Tucumán,
Argentina(3) INFINOA, CONICET-UNT, 4000 Tucumán Argentina(4) CNRS, Universite de Nantes, Nantes Atlantiques Universites, Laboratoire de Planetologie etde Geodynamique, Nantes, France

The trajectory of energetic particles trapped by the geomagnetic field is usually definedby three cyclic motions: gyration, bounce along field lines, and drift around the earth, which are
all controlled by this field. The geomagnetic field, in turn, has been declining at a rate of ~5%
every hundred years since at least ~1840. A possible future scenario is a steady decrease of thedipole component with a field complexity increase through the relative growth of non-dipolar
components. The expected variations in trapped particle trajectories, which describe an overall
drift shell, is analyzed in the present work through an analytical approach helped by computer
simulations using the Rice Adaptive Particle Tracer (RAPT) that is a Python framework for
tracing relativistic charged particles in general electromagnetic fields. The main results are thedecrease of drift shells mean distance to the Earth, decrease of mirror point altitudes, increaseof conjugate mirror points asymmetry, and the split of radiation belts for pure multipolar
configurations. The idealized and simplified structures here analyzed could shed light on the
study of plausible radiation belt enhancements during polarity transitions which can have widerange implications for man-made technologies that operate in space.

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Inter-Hemispheric Comparisons of the Ground Magnetic Response during Past and Future
Eclipses
M. Hartinger, M. Freeman (British Antarctic Survey), J. Baker (Virginia Tech), J. Weygand(UCLA), T. Edwards (Technical University of Denmark), X. Shi (Virginia Tech), S. Coyle (Virginia
Tech), C.R. Clauer (Virginia Tech), Z. Xu (Virginia Tech), D. Weimer (Virginia Tech)

During a solar eclipse, reductions in solar illumination affect the ionosphericconductivity and can in turn perturb the geomagnetic field and related magnetosphereionosphere current systems. We discuss (1) how expanded networks of ground magnetometers inboth hemispheres can be used to characterize magnetosphere-ionosphere coupling processes, (2)how eclipses serve as unique experiments to test predictions for magnetosphere-ionosphere
coupling processes, and (3) whether past eclipses significantly perturbed the geomagnetic field.
The focus of this presentation is on ground magnetometer and SuperDARN radar observations
in both hemispheres during the 23 November 2003 total solar eclipse event (including
observations at Syowa station and other locations in East Antarctica). We place the observations
from this eclipse in context with other eclipse events. We also use results from past eclipses toinform plans for satellite and ground-based measurements during the upcoming 4 December
2021 Antarctic eclipse.

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Investigating EMIC/IPDP source regions with conjugation ERG-PWING observations
A. Hendry, C. Rodger (University of Otago), A. Matsuoka (Kyoto University), Y. Miyoshi, K.
Shiokawa, S. Imajo, (ISEE, Nagoya University), I. Shinohara (ISAS)

Despite over 60 years of study, there is still much we are yet to fully understand about
Electromagnetic Ion Cyclotron (EMIC) waves. While recent flagship missions such as the Van
Allen probes and Arase have proved invaluable for furthering our knowledge of EMIC waves, thenature of these waves makes it difficult to study them from a single location. It is only throughthe combined effort of in-situ and ground-based instrumentation that we are able to properly
understand and explain fundamental characteristics of EMIC waves.
One such aspect of EMIC waves that is still a matter of considerable inquiry is theinteraction between EMIC wave and radiation belt electrons. In recent years there has been an
increased interest in EMIC-driven electron loss from the radiation belts, with numerous studies
showing electron precipitation occurring at sub-MeV energies, far lower than previously thoughtpossible. Precipitation at these energies has the potential to be important not only for radiation
belt dynamics, but also for upper atmosphere chemical balance and as a driver of ozone loss.
Some studies have suggested that the primary driver of this sub-MeV electron precipitation may
be IPDP waves (intervals of pulsations with decreasing period), a subset of EMIC waves first
identified in the early 1960s, but still fairly poorly understood.
In this talk we will discuss the limitations of our understanding of IPDP-type waves, andhow we can use a combination of in-situ measurements from ERG, PWING, and other data
sources to help fill these gaps in our knowledge, and further our understanding of IPDP waves,and EMIC waves in general.

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Spatial evolution of injected energetic electrons as observed by Arase and Van Allen Probes
T. Hori, Y. Miyoshi (ISEE, Nagoya University), T. Mitani (JAXA/ISAS), S. Kurita (RISH, Kyoto
University), M. Teramoto (Kyutech), T. Takashima, I. Shinohara (JAXA/ISAS), A. Matsuoka(WDC/Kyoto, Kyoto University), S. G. Claudepierre, J. F. Fennell, J. B. Blake (Aerospace
Corporation), C. A. Kletzing (University of Iowa)

In this study, we investigate how drifting energetic electron populations evolve in the
inner magnetosphere, using the Arase and Van Allen Probes (RBSP) satellites. Electrons andions of the plasma sheet origin are energized up to tens to hundreds of keV and abruptly
transported on the night side into geosynchronous distance and even further inward during
substorms, which is referred to as substorm injection. Then injected electrons drift eastward anddisperse along their drift path with azimuthal drift velocities depending on their energies.
Extensive observations with geosynchronous satellites have shown that energy dispersion
signatures can be quantitatively explained by magnetic drift velocities, while its two-dimensional(radial and azimuthal) evolution has not been well examined except for a few case studies where
many satellites were available simultaneously at different radial distances and local times. In
this regard, we examine simultaneous observations by Arase and RBSPs to examine how injectedenergetic electrons spread radially in the course of their eastward drift. A case study in which
the three satellites were located on the dawn side shows that Arase (L ~ 7.7, MLT ~ 10h) and
RBSP-B (L ~ 5.8, MLT ~ 4h) observed an energy-dispersed electron population nearly at the sametime (within a few minutes), despite the large difference in MLT sector. This result strongly
suggests that the leading edge of energetic electrons goes significantly ahead at farther radial
distances even if they have started drifting at the same MLT, forming a spiral-shaped drift front.
Our statistical study shows that such events are frequently found in the dawnsidemagnetosphere, in addition to those showing later arrival of electrons at a later MLT. Based on
many simultaneous observations, we address how the spatial shape of drifting populations looks
like and how it evolves as drifts eastward from night to the dayside.

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Active auroral arc powered by accelerated electrons from very high altitudes
S. Imajo (ISEE, Nagoya University), Y. Miyoshi (ISEE, Nagoya University), Y. Kazama (ASIAA),
K. Asamura (ISAS, JAXA), I. Shinohara (ISAS, JAXA), K. Shiokawa (ISEE, Nagoya University),
Y. Kasahara (Kanazawa University), Y. Kasaba (PPRAC, Tohoku University), A. Matsuoka(DACGSM, Kyoto University), S.-Y. Wang (ASIAA), S. W. Y. Tam (NCKU), T.‑F. Chang (NCKU),
B.‑J. Wang (ASIAA), V. Angelopoulos (UCLA), C.-W. Jun (ISEE, Nagoya University), M. Shoji(ISEE, Nagoya University), S. Nakamura (ISEE, Nagoya University), M. Kitahara (ISEE,
Nagoya University), M. Teramoto (Kyutech), S. Kurita (RISH, Kyoto University), T. Hori (ISEE,
Nagoya University)

Bright, discrete, thin auroral arcs are a typical form of auroras in nightside polar regions.
Their light is produced by magnetospheric electrons, accelerated downward to obtain energies ofseveral kilo electron volts by a quasi-static electric field. These electrons collide with and excite
thermosphere atoms to higher energy states at altitude of ~100 km; relaxation from these states
produces the auroral light. The electric potential accelerating the aurora-producing electrons has
been reported to lie immediately above the ionosphere, at a few altitudes of thousand kilometres.
However, the highest altitude at which the precipitating electron is accelerated by the parallel
potential drop is still unclear. Here, we show that active auroral arcs are powered by electrons
accelerated at altitudes reaching greater than 30,000 km. We employ high-angular resolution
electron observations achieved by the Arase satellite in the magnetosphere and opticalobservations of the aurora from a ground-based all-sky imager. Our observations of electron
properties and dynamics resemble those of electron potential acceleration reported from lowaltitude satellites except that the acceleration region is much higher than previously assumed.
This shows that the dominant auroral acceleration region can extend far above a few thousand
kilometres, well within the magnetospheric plasma proper, suggesting formation of theacceleration region by some unknown magnetospheric mechanisms.

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Computer simulations of precipitating energetic electrons through chorus-wave particle
interactions
Y. Ito(ISEE, Nagoya University), S. Saito(NICT) and Y. Miyoshi(ISEE, Nagoya University)

Whistler mode chorus waves cause scattering and acceleration of energetic electrons in
the inner magnetosphere, and recent Arase observations identified that chorus waves cause thepulsating aurora. The interaction processes have been modeled as diffusions in the velocity space,and it has been supposed that the scattering rate increases with increasing the wave amplitude.
However, the wave-particle interactions with chorus waves are non-linear process, so that it isexpected that the scattering rate does not simply depend on the wave amplitude. In this study,
we investigate chorus wave amplitude dependence of electron scattering using the GEMSIS-RBW
simulation code. The GEMSIS-RBW simulation calculates variations of local pitch angle andenergy of each test particle by the imposed chorus waves. In this simulation, chorus bursts thatconsist of multi rising tone elements are imposed at the equatorial plane, and these waves
propagate along the field line with L= 4 by calculating the Maxwell equations.
We calculate the trajectory of a number of electrons with various energy with various wave
amplitudes. We analyzed the electron motion in the phase space as well as the parameter ρ[Bortnick et al., 2008] that is a proxy of the ratio of the wave-induced and the backgroundinhomogeneity effects for the momentum change of the resonant electron. We identified thatthe phase trapping effect decreases the precipitating flux and generates the butterfly type pitch
angle distributions.

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Overview of the DSX Satellite Mission
W. R. Johnston (AFRL), G. P. Ginet (MITLL), Y.-J. Su, M. J. Starks, J. P. McCollough, and J.
Carilli (AFRL), U. Inan (Koc Univ., Stanford Univ.), D. Lauben and I. Linscott (Stanford Univ.),
P. Song, B. W. Reinisch, I. A. Galkin, and J. Tu (Univ. of Massachusetts-Lowell), Y. Miyoshi (ISEE,
Nagoya Univ.), and the DSX and Arase Science Teams

Launched on 25 June 2019 into a medium-Earth orbit, the Demonstration and Science
Experiments (DSX) satellite is comprised of a number of experimental payloads designed to: (1)validate models of Very Low Frequency (VLF) wave injection, propagation and particle scatteringin the magnetosphere; (2) measure the distribution of energetic particles and plasmas; and (3)investigate radiation effects on advanced spacecraft technologies. The primary mission goal of
DSX is to determine the feasibility of injecting VLF waves into the magnetosphere and explore
the dynamics of magnetospheric wave-particle interactions in a controlled manner. The WaveParticle Interactions Experiment, which includes a VLF transmitter (UMass/Lowell), broadband
receiver (Stanford University) and a magnetometer (UCLA), has been successful in injecting VLF
waves into the far-field. This has been demonstrated through bistatic detection of DSX
transmissions by the Arase satellite and monostatic detection of DSX pulses reflected off thebottom of the magnetosphere. An overview of the DSX mission and highlights of the first year ofoperation will be presented.

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Inner Magnetosphere Plasma and Field Dynamics
V. K. Jordanova

In this lecture, we review the dynamics of energetic particles in the near-Earth spaceenvironment, which are strongly coupled to the variations of the electric and magnetic fields. On
one hand, the electric and magnetic fields guide the particle acceleration and loss as particles
drift through the inner magnetosphere and precipitate into the ionosphere or flow out of thedayside magnetopause. On the other hand, the fields themselves are influenced by the particle
dynamics, since the magnetic field depends on the plasma pressure, while the electric fielddepends on the ionospheric conductance and particle precipitation. In addition, the major
processes that contribute to particle loss such as charge exchange, Coulomb collisions, and waveparticle interactions and their aeronomical effects are discussed.

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The characteristics of EMIC (ElectroMagnetic Ion Cyclotron) waves in the magnetosphere using
the Van Allen Probes and Arase observations
C.-W Jun, Y. Miyoshi, S. Nakamura, S. Imajo, M. Shoji (ISEE, Nagoya University), C. Yue(Peking University), J. Bortnik, L. Lyons (AOS, UCLA), Y. Kasahara (Kanazawa University), Y.
Kasaba, F. Tsuchiya, A. Kumamoto (Tohoku University), S. Matsuda K. Asamura, I. Shinohara(ISAS, JAXA), and A. Matsuoka (Kyoto University)

Electromagnetic ion cyclotron (EMIC) waves have been driven by temperature
anisotropy of energetic ions near the magnetic equator. These waves constitute a significant loss
process of energetic protons and sub-relativistic electrons through pitch-angle scattering by
wave-particle interactions. We investigated the statistical characteristics of EMIC waves in themagnetosphere observed by the Van Allen Probes (RBSP) and Exploration of energization andRadiation in Geospace (Arase) satellite. In our recent studies, we found that EMIC waves show
significantly different characteristics at the different peak occurrence regions depending on
geomagnetic environments. During disturbed geomagnetic conditions, EMIC waves are
predominantly observed in the afternoon sector where cold plasma dominates (L < 6). Thesewaves mainly appear in the morning sector at L > 8 during extremely quiet conditions. On thedayside, EMIC waves have peak occurrence at L~4-8 in the recovery phase of a magnetic storm.
This observational fact suggests that the major driver of EMIC waves depends on geomagnetic
conditions and environments. In this presentation, we show spatial distributions and wave
properties of EMIC waves in the magnetosphere, and discuss possible free energy sources causing
EMIC waves at different regions. We will demonstrate the influence of different generation
processes of EMIC waves on energetic proton distributions using in-situ satellite observations
and theoretical model calculations.

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Study of Phase Relationship of Sunspot Numbers with F 10.7 cm Solar Radio-Flux and Coronal
Index using Wavelet-Transform Technique
S.K. Kasde and D.K. Sondhiya

In this work advanced wavelet based techniques such as Continuous Wavelet transform(CWT), Cross Wavelet Transform (XWT) and Cross-Recurrence Plot’s (CRP) are used to study thephase relationship between Sunspot numbers, solar radio flux at 10.7cm Coronal index. All theparameters were analyzed for complete solar cycle 23 and ascending phase of solar cycle 24 (i.e.
time span 1 January 1996-31 December 2013) on the basis of daily and monthly count. We haveidentified the essential characteristic of solar cycle maxima and found the asynchronous
behaviors between the parameter analyzed. Our results are in agreement with the previous
findings and suggested that the solar activity maxima occur at least twice during a cycle: first,
near the end of the increasing activity phase and then in the early beginning years of thedeclining phase. It was also found that odd and even numbered Solar Cycles(i.e. solar cycle 23
and 24) are essentially not in phase and have a phase difference of two months. The sunspot
number shows significant phase relation of 27 days with solar radio-flux and coronal index (CI)
corresponding to one solar rotation, during the maximum phase of the cycles. It suggests that themagnetic field system originated in the photosphere in form of active regions and theirevaluations are inadequately coupled in the entire solar cycle.

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Auroral substorm events as seen from Syowa-Arase-Tjornes conjugate observations
Ryuho Kataoka, Herbert Akihito Uchida, and Kiyoka Murase (NIPR)

We introduce our recent papers on substorm-related auroral phenomena as obtained
from the event studies of magnetically conjugate observations among Syowa station in the
Antarctic, the Arase satellite, and Tjornes in Iceland. The major topics to be introduced are theconjugacy of breakup auroras and the mesospheric ionization during different phase of substorms.

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Energetic particle precipitation characteristics and its atmospheric impacts derived fromelectron density profile measurements
A. Kero (SGO/OU)

The height-dependent electron density profile, and its time-dependent response tovariable ionising radiation from space, yields information on both the ionisation source processes(solar electromagnetic radiation, energetic particle precipitation, cosmic rays) and theirconsequences on the atmosphere (changes in chemistry, energetics and dynamics).
An inversion technique for determining the EPP characteristics, i.e., precipitation flux
density spectrum and ionisation rate profile is introduced. In addition, potential chemicalconsequences of the energetic particle precipitation are assessed. In this approach, a detailed ion
chemistry model (SIC) is used as a time-dependent forward model in the MCMC based inversion.

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The Role of Injected Ring Current Ions in Generating EMIC Waves and Scattering Radiation
Belt Particles
Hyomin Kim, Sung-Jun Noh, Ilya Kuzichev, Louis Lanzerotti, Andrew Gerrard (New Jersey
Institute of Technology), Quintin Schiller (Space Science Institute), Mark Engebretson (Augsburg
University), Khan-Hyuk Kim (Kyung Hee University), Marc Lessard, Harlan Spence (Universityof New Hampshire), Dae-Young Lee (Chungbuk National University), Jürgen Matzka (GFZ
Potsdam), Tanja Fromm (Alfred-Wegener Institute), Lauren Blum (University of Colorado,
Boulder)

We report on observations of electromagnetic ion cyclotron (EMIC) waves and theirinteractions with injected ring current particles and high energy radiation belt electrons. The
magnetic field experiment aboard the twin Van Allen Probes spacecraft measured EMIC waves
and proton flux data from the spacecraft show that the waves were associated with particle
injections. The wave activity was also observed by a ground-based magnetometer near the
spacecraft geomagnetic footprint over a more extensive temporal range. Phase space density(PSD) profiles, calculated from directional differential electron flux data from Van Allen Probes,
show that there was a significant energy-dependent relativistic electron dropout over a limited
L-shell range during and after the EMIC wave activity. The NOAA spacecraft observed
relativistic electron precipitation associated with the EMIC waves near the footprint of the Van
Allen Probes spacecraft. The observations suggest EMIC wave-induced relativistic electron loss
in the radiation belt. In addition, a statistical survey of EMIC wave occurrences has been
conducted using Van Allen Probes data over the entire mission period (September 2012 to July2019). Approximately 10% of the entire set of EMIC waves were generated or intensified duringring current ion injection events. Injection-associated EMIC waves occurred predominantly overthe noon to dusk sectors and peak occurrences coincided with where the plasmaspheric plume ismost likely to occur. The particle data from the spacecraft positioned in the heart of the ring
current system present complex, energy-dependent hot proton anisotropy variations during mostof the injection-associated EMIC waves. We aim to understand the role of injected ring current
ions in generating EMIC waves and scattering radiation belt particles.

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On the use of three-component ELF/VLF measurements of radio atmospherics in investigationof lightning related phenomena
I. Kolmasova (IAP CAS and Charles University) and O. Santolik (IAP CAS and Charles
University)

We present results of three-component ELF/VLF measurements of radio atmospherics,
which we have recorded in a favorable electromagnetic environment on the summit of La GrandeMontagne (1028 m, 43.94N, 5.48E), Plateau d Albion, France.
These measurements were used to obtain information about properties of causative
lightning strokes of transient luminous events or long-duration whistler echo-trains. We also
analyzed tweek atmospherics to study the properties of the winter-time Earth-ionosphere
waveguide.
To detect radio atmospherics we used a 10-cm spherical electric antenna located 2 mabove the ground and two 12-turn magnetic loop antennas of 4 square meters oriented in E-W
and S-N directions. The sensors were coupled with a receiver sampling at 50 kHz. The 3component measurements allowed us to determine the direction of arrival of recorded
atmospherics. The polarity of causative lightning strokes was derived from the polarity of their
ground wave pulses in the electric field records. Using the Hilbert transform we calculated theanalytical signal and instantaneous frequency of the recorded dispersed tweek atmospherics andestimated their propagation distance. The magnetic field records of these dispersed atmospherics
were examined to obtain their polarization properties.

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Statistical Properties of Auroral Kilometer Radiation
V.I. Kolpak, M.M. Mogilevsky, D.V. Chugunin,A.A. Chernyshov, I.L. Moiseenko (SRI RAS,
Moscow), A. Kumamoto, F. Tsuchiya (Tohoku University), Y. Kasahara (Kanazawa University),
M. Shoji, Y. Miyoshi (Nagoya University), I. Shinohara (ISAS)

In the present study, a detailed statistical analysis of more than 20 months of continuous
AKR measurements on the ERG satellite (also called Arase) is carried out. This made it possible
to confirm the previously obtained results on the location of AKR sources and seasonal changes
in the radiation intensity. Open issues about the processes in the AKR source can be solved using
data on the radiation pattern under various geomagnetic conditions. In order to get answers tothese questions, an estimate is made of cone angle of directional diagrams in the evening andmorning sectors of the Earth’s magnetosphere.

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Evolution of the energetic electron flux observed by ARASE satellite and simultaneous aurora
over Kola Peninsula
B. V. Kozelov, A.V. Roldugin, Z. V. Dashkevich, A. G. Demekhov (PGI, Russia), S. Oyama (Nagoya
University, Japan), Y. Miyoshi (Nagoya University, Japan), S. Kasahara (University of Tokyo,
Japan)The data of simultaneous observation of the energetic electron flux by ARASE satellite
and aurora by ground-based all-sky cameras in Murmansk region (Russia) have been analyzed
for time interval 00:00-01:00 UT, March 31, 2017. The energetic spectra of middle-energy
electrons observed by MEPE detectors in the loss cone have been used for simulation of theaurora emissions in the atmosphere. The temporal evolution of the simulated emission intensity
has been compared with emissions observed near the magnetic field-aligned footprint point forthe satellite. The data from cameras located in Apatity and Lovozero have been used. It was
found that the projection along magnetic field has been distorted by developing disturbance.
These distortions have been analyzed by magnetosphere model simulation.

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Contribution of electron pressure to ring current and ground magnetic depression using RAMSCB simulations and Arase observations during geomagnetic storms
Sandeep Kumar, Y. Miyoshi (ISEE, Nagoya University) V. K. Jordanova, M. Engel (Los Alamos
National Laboratory, Los Alamos, NM, USA) K. Asamura (ISAS/JAXA, Japan), S. Yokota (Osaka
University, Japan), S. Kasahara (University of Tokyo, Japan), Y. Kazama, S-Y. Wang (ASIAA,
Taiwan), T. Mitani (ISAS/JAXA, Japan), K. Keika (University of Tokyo, Japan), T. Hori, C. Jun(ISEE, Nagoya University), and I. Shinohara (ISAS/JAXA, Japan)

Understanding the physical processes that control the dynamics of energetic particles in
the inner magnetosphere is important for both space-borne and ground-based assets essential tothe modern society. The storm time distribution of ring current particles in the innermagnetosphere depends strongly on their transport in evolutions of electric and magnetic fields
along with acceleration and loss. In this study, we investigated the ring current particle
variations using observations and simulations. We compared the ions (H+, He+, and O+) andelectrons flux variations using Arase observations with the self-consistent inner magnetospheremodel: Ring current Atmosphere interactions Model with Self Consistent magnetic field (RAMSCB) during 7-8 November 2017 geomagnetic storm. We investigated the contribution of thedifferent species (ions and electrons) to the magnetic field deformation observed at groundmagnetic stations (09-45° MLat) using RAM-SCB simulations. The results show that the ions are
the major contributor with ~ 88 % and electrons contribute ~ 12% to the ring current pressure.
It is also found that the electrons contribute to ~ 18 % to the ring current in dawn-side during
the main phase of the storm. Thus, electrons contribution to the storm time ring current isimportant and should not be neglected.

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Disturbances of the Subpolar ionosphere over the Asian part of Russia during the geomagnetic
storms of 2017-2020
V. Kurkin, A. Oinats, A. Beletskii, R. Vasilev, Yu. Kalashnikov, R. Marchuk, N. Polekh, N.
Zolotukhina (ISTP SB RAS) and K. Shiokawa, N. Nishitani (ISEE,Nagoya University)

The paper presents the results of a comprehensive analysis of data from optical,
radiophysical and magnetometric instruments during ten weak and moderate geomagnetic
storms of the autumn-winter seasons 2017-2020. We used the measurement data of the ISEE,
Nagoya University instruments (broad-beam riometer system, all-sky airglow imager system,
VLF/ELF loop antenna system) and ISTP SB RAS (three-component induction magnetometer
LEMI-30,wide-angle

RGB-camera,

patrolspectrometerandphotometerwithsiliconphotomultipliers detectors) at the Istok station, the complex of radiophysical instruments of the
ISTP SB RAS located in the Asian part of Russia (the Yekaterinburg HF radar, ionosonde DPS4 in Norilsk, chirp oblique incidence sounding along Norilsk-Irkutsk and Magadan-Irkutsk
paths) and 2 SuperDARN Hokkaido radars (East / West) operated by ISEE, Nagoya University.
The features of spatial distributions and temporal variations of disturbances in this sub-polar
ionospheric region under conditions of low activity at the end of the 24th solar cycle are revealed.
Specific artifacts in ELF/VLF loop antenna system data, which could influence on thedata interpretation, were revealed. We analyze the occurrence rate of the artifacts, discuss their
possible sources and ways of dealing with their interference. The prospects of experimental
studies related to the introduction of the Magadan HF radar are outlined.

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The relationship between substorm-onset related IPDP-type EMIC waves and drift-shell
splittingMarc R. Lessard (Univ of New Hampshire), Michelle Salzano (Univ of New Hampshire), Sungjun
Noh (Univ of New Jersey), Hyomin Kim (Univ of New Jersey), Mark J. Engebretson (Augsburg
University), Richard Horne (British Antarctic Survey), Mark Clilverd (British Antarctic Survey),
Akira Kadokura (National Institute of Polar Research), Yoshimasa Tanaka (National Institute ofPolar Research), Khan-Hyuk Kim (Kyung Hee University), Jürgen Matzka (GFZ Potsdam), Tanja
Fromm (Alfred Wegener Institute) and Colin Waters (University of Newcastle)

The relationship between Pi1B and IPDP-type EMIC waves was first discussed in 1971
by R. R. Heacock, who found that Pi1B and IPDPs occur near-simultaneously in groundobservations, though they are spatially separated; IPDPs appear at lower geomagnetic latitudes(60-65 degrees) than PiBs, which are more prominent at ~70 degrees. It is well understood that
Pi1B waves are correlated with substorm onset, but it is often overlooked that IPDP-type EMIC
waves can be as well; they are thought to be associated with increased fluxes of 40-60 keVsubstorm-injected protons, which was first modeled in 1980 by F. Søraas. Others have postulated
that IPDP waves are excited by protons that undergo gradient-curvature drifting and eventuallyinteract with the cold plasmapause population, but oft-neglected is the important role that driftshell splitting plays in the process. Our research attempts to understand the different pathways
that Pi1B and IPDPs take from their shared origin in substorm onset to their distinct
observations on the ground, including the effects of drift-shell splitting en route. We present twocase studies showcasing data from an array of four ground-based Antarctic magnetometers thatcover the evening sector, as well as in-situ magnetometer data, proton fluxes, and proton pitch
angles from the Van Allen Probes. Our observations corroborate the separation in MLAT between
Pi1B and IPDPs and additionally pinpoint a separation in MLT, with IPDPs occurring roughly
two hours earlier than Pi1B observations. Building from our observations we model the driftshell splitting which injected particles undergo post-onset, with the expectation that this work
will provide an improved model for the process.

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Ionospheric climatology at South American sector using amplitude scintillation index S4
E. Macho, E. Correia (Universidade Mackenzie)

Scintillations are caused by ionospheric irregularities and can affect trans-ionosphericradio signals. One way to understand and predict such irregularities is through ionosphericclimatology using scintillation indexes during different periods of times of solar cycle in different
regions, including the Equatorial Ionospheric Anomaly (EIA) and the South Atlantic Magnetic
Anomaly (SAMA) regions. In this work we are using amplitude scintillation index S4 during thefull solar cycle 24 at South American sector. Preliminary results show a significant intensificationof ionospheric fluctuation at northern and southern crest of EIA, especially during the southernhemisphere’s spring/summer seasons, with a higher increase during solar maximum. In the
SAMA region, where the intensity of field magnetic lines is lower, the fluctuation is much higher
during the spring/summer months of solar maximum.

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Ionosphere Behavior during the Geomagnetic Storms over the different latitude Regions
Bhupendra Malvi1, Sharad C Tripathi2, P. K. Purohit3
1. Department of Electronics, Barkatullah University, Bhopal - 462026
2. Physics Division, School of Advanced Sciences and Languages, VIT Bhopal University, BhopalIndore Highway, Kothri Kalan, Sehore - 466114
3. National Institute of Technical Teachers’ Training and Research, Shamla Hills, Bhopal –462002In the present study, we have done the investigation of the ionospheric perturbations
during geomagnetic storms which are disturbed conditions in earth’s magnetic field.
Geomagnetic storm leads to a number of disruptions in technological applications such as spacevehicle operation, interrupt radio communication, and disrupt power grids. Quantitative analysis
has been done in three different storm criterions, strong, weak and moderate ones and their
response in the ionosphere has been investigated over different latitude. Fair enough results
have been witnessed in different longitudinal and latitudinal regions over the globe. An attempt
has been made to find some qualitative and quantitative relationship between the storm andionospheric perturbations with different latitudinal indices.

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Why it is important to have simultaneous ground-based ELF-VLF observations in every satellite
project?
J. Manninen (SGO, University of Oulu), C. Martinez-Calderon (ISEE, Nagoya University), andT. Turunen (SGO, University of Oulu)

The ERG (Exploration of energization and Radiation in Geospace) project is a mission to
elu-cidate acceleration and loss mechanisms of relativistic electrons around Earth during
geospace storms. The project consists of a satellite observation team, a ground-based network observation team, and integrated data analysis/simulation team. After launch, the ERG satellite
was renamed Arase.
All satellite projects observing geospace also need reliable and high-quality groundbased data in order to explain different kinds of events observed by the satellites. While the Arasesatellite has several particle, plasma waves and magnetic field instruments, it is sometimes
difficult to separate spatial and temporal features in the observations. In such cases, theavailability of ground-based instruments can be very helpful.
It is also important to remember that most of satellites are moving very rapidly. They
are covering several L shells, many longitudes, different MLTs, nightside/dayside, etc. within
hours or even minutes. It means that every single satellite data sample is related to a different
location of the satellite, i.e., such data easily shows the spatial distribution of the observed events.
If we want to study temporal changes of the same events we need ground-based observations.
In this presentation, we will show ground-based ELF-VLF observations made at Kannuslehto(KAN) in northern Finland during the conjugated observation campaigns of Arase.

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Recent characteristics and propagation of unusually high frequency VLF emissions at
Kannuslehto, Finland
C. Martinez-Calderon (ISEE, Nagoya University), J. K. Manninen (SGO, University of Oulu), J.
T. Manninen (SGO, University of Oulu), and T. Turunen (SGO, University of Oulu)

First reported by Manninen et al., 2016, Kannuslehto High-Frequency VLF (KHF-VLF)
waves have been observed at the ground station of Kannuslehto in northern Finland (KAN,
MLAT=64.4°N, L=5.46) since 2006. These VLF emissions are observed above the local electron
gyrofrequency for the L-shell of KAN (fce ~ 5- 6 kHz) where these type of waves should not usually
propagate. KHF-VLF have different spectral features, but are mostly composed of hiss-like bursts
with durations of a few seconds. KHF-VLFs have been observed in at least 60% of the observation
campaign days at KAN, and seem linked with high solar activity.
Using case studies and statistical analysis from the 2017-2020 KAN campaigns, we
present the general properties and propagation characteristics of KHF-VLF waves. We show
examples of KHF-VLF, their occurrence rate as a function of MLT, wave type, periodicity, andnumber of bursts. We found that their occurrence is related to more usual VLF waves suggesting
their generation is not ionospheric in nature. Using observed frequencies combined withconjugated events and ray tracing, we discuss the likely location of the source of these emissions,and the mechanisms allowing for propagation to the L-shells of KAN. Occurrence of KHF-VLF
waves appear positively correlated with AE index, however their detection on the ground iscoupled with a local decrease of the magnetic field.

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Identifying the Physical Mechanisms to Explain the Extreme Plasmaspheric Erosion for the
September 2017 Storm
N. Maruyama (CU & NOAA), C. Ferradas, M.-C. Fok (NASA GSFC), Y. Obana (Osaka ElectroComm. Univ.), K.K. Hashimoto (School of Agriculture, Kibi International Univ.), M. Henderson(LANL), A. Menz, B. Kress, S. Califf (CU &amp; NOAA), S. Thaller (CU LASP), A. Shinbori, M.
Nosé, Y. Otsuka, N. Nishitani, T. Hori, Y. Miyoshi (ISEE, Nagoya Univ.), A. Kumamoto (Tohoku
Univ.), F. Tsuchiya (PPARC, Tohoku Univ.), S. Matsuda, I. Shinohara (ISAS), A. Matsuoka (Kyoto
Univ.), Y. Kasahara (Kanazawa Univ.), A. Yoshikawa (Kyushu Univ.)

An extreme erosion of the plasmasphere (LPP < 2) occurred during the September 2017storm. The cold electron density is identified from the upper limit frequency of upper hybrid
resonance waves observed by the Plasma Wave Experiment instrument onboard the Explorationof energization and Radiation in Geospace/Arase satellite. The electron density profiles revealthat the plasmasphere was severely eroded during the recovery phase of the storm and theplasmapause was located at L = 1.6 at 23 UT 8 September 2017. The degree of the severity ismuch more than what is expected from the relatively moderate value of the SYM‐H minimum(−146 nT). Observations of ground-based magnetometers near the magnetic equator indicate along duration penetration electric field. It is not fully understood why the electric field
disturbance lasted for several hours and whether it was caused by the long duration penetrationelectric field. In this presentation, we will address these questions by using numericalsimulations of a combination of two physics-based models: the Ionosphere-PlasmasphereElectrodynamics (IPE) model and Comprehensive Inner Magnetosphere Ionosphere (CIMI)
model. Furthermore, we will discuss the role of the ionospheric conductance in the electric field
disturbance.

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Experimental observation of the transverse Alfvénic resonator for Pc4 pulsations: a Van Allen
Probes case study
Olga S. Mikhailova, Pavel N. Mager, Olga V. Mager, Dmitri Yu. Klimushkin

A Pc4 ultralow frequency wave was detected nearby the plasmapause by spacecraft Van
Allen Probes B. The strong periodical modulation of the wave was observed that means a beatingof oscillations close in frequency. There were at least two harmonics with frequencies of 15.3 and13.6 mHz. It is shown that these harmonics can be the eigenmodes of the transverse resonator
near the plasmapause at the local maximum of the Alfvén velocity. It was found that the observed
wave was in a drift resonance with energetic 80-keV protons. An unstable bump on taildistribution of protons simultaneously observed with the wave is supposed to be source of the
wave. The estimate of the azimuthal wave number m is about −100, that means a westward
propagating azimuthally small-scale wave.
The work was supported by the Russian Science Foundation under grant 18-17-00021.

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Geomagnetic and solar activity in solar cycles 23 and 24
R. Miteva (IANAO), S. W. Samwel (NRIAG)

We present statistical analysis of geomagnetic storms and accompanied solar activity
events (solar flares, coronal mass ejections and energetic electrons) in solar cycles 23 and 24.
Both directions of associations are explored for each paired phenomena. The results are
summarized and discussed.

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Highlight and future perspective of the ERG/Arase project
Y. Miyoshi (ISEE, Nagoya University)

The ERG project aims to understand variations of gepspace and radiation belts bycomprehensive research teams consist of the satellite, the ground-based observations andsimulations. The Arase satellite has observed dynamical evolutions of geospace since March 2017and is providing new findings from collaborative researches with ground-based observations andother satellite observations. In this lecture, we will present several highlight results from
Arase/ERG project and discuss future perspectives for geospace research.

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Statistical investigation of cross energy coupling during magnetic storms; Arase observations
Y. Miyoshi, S. Kurita, R. Kataoka, T. Mitani, I. Shinohara, M. Teramoto, I. Park, S. Kasahara, S.
Yokota, K. Keika, T. Hori, N. Higashio, S. Imajo, C-W.Jun, A. Matsuoka, F. Tsuchiya, A.
Kumamoto, Y. Kasahara, S. Matsuda, M. Shoji, D. Turner, and J. F. Rippole

The Arase satellite has observed a number of magnetic storms since March 2017, whichcorresponds to the declining phase of the solar cycle 24. We performed the superposed epoch
analysis of energetic electrons and related parameters in the inner magnetosphere using dataobtained by Arase satellite. The electron measurements in the wide energy range are utilized toclarify the cross energy coupling process during storms. The energetic electron flux variations
strongly depend on the storm phase and L-shell as well as the electron energy. Electrons withenergies ranging from tens of keV to ~200 keV largely increase their fluxes in the outer radiation
belt during the main phase, and the electron fluxes gradually decrease during the recovery phase.
The sub-relativistic/relativistic electrons show different flux variations. The electron fluxes
decrease at the outer part of the outer belt during the main phase, and the fluxes gradually
increase from the inner part of the outer belt during the recovery phase. The variations in theenergy spectrum and phase space density indicate that the local accelerations mainly contributeto enhancements of MeV electrons in the outer belt. In this study, we discuss variations in theenergy spectrum by considering different roles of each energy range in the cross energy coupling
process, i.e., source population for generating waves, seed population for subsequent acceleration,and relativistic electrons.

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The ionospheric response to 27 September magnetic storm on 2017 at the equator.
Heba S.Mohamed(CIC) , Ayman M. Mahrous (E-Just)

In this study we monitor the ionospheric response for 26th September magnetic storm
at the magnetic equator over Asia and South America through the magnetic equator using IGS
stations and some magnetic and solar parameters. The used stations are CUSV from Thailand(13.7 lat/100.5 long) and KOUR from French Guiana (5.2 lat/-52.8 long) geographically. We
observed a magnetic disturbance -100 nT in DST due to a south ward Bz component triggered
from a high speed solar wind from coronal hole 32. The solar wind gone beyond 700km/s and the
AE index is 1000nT. The kp index is 7. The ionospheric response (time since the SSC till the
maximum value of DTEC) within 31 hr range in Thailand. The ionospheric response in French
Guiana within the range 26 hr. however it occurs in the nightside. Despite the difference inlocation and local time occurrence of the stations, the both stations show a positive ionosphere
TEC value.

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Kinetic instability driven by using non-Maxwellian kappa (k) and (r, q) distribution function.
Thesis in progress
Electrosatic model basically such as ion-acoustic and dust-acoustic and Langmuir waves
generated in plasma have been usually study by using fuild and Boltzmann kinetic vlasov models.
These studies had assumed Maxwellian velocity distribution function for the plasma particle.
However, with more empirical data becoming available it is realize that the Maxweelian is not arealistic distribution under all situation. Because Maxwellian distribution is applicable to asystem in thermodynamics equillibrium. Howeeve, a realistic system may be far away from thisstate since the plasma may be subject to a whole variety of different effect.
Vasyliunas is the first to apply the general form of the non-Maxwellian (kappa)
distribution. On the basis of theory, application and observation, it is notice that the space andastrophysical environment (plasma) often contain superthermal particle and high energy tails
that the kappa distribution offer a useful fit to there “spectral” distribution. So msotly spaceplasma problem can be moduled more affectively by superposition of kappa distribution fumction
intead of Maxwellaian distribution fuction.
The generalize kappa distribution function is reduce back to Maxweellian behaviour. In
the limit as κ → ∞ , the Kappa distribution approaches the well know Maxweellian
distribution function.The condition κ > 1/2 is necessary for this integral to converge.
The another non-Maxweellian distribution we introduce a three dimenssional
generalized (r, q) distribution. This distribution function is of a more genral form than the above
mentioned kappa distribution and hence better suited to module plasmas exhibiting
characteristic which cannot explain by the kappa distribution function. This distribution function
containing spectral indices r and q. We also note that the spectral indices r and q satisfy theconstraints q>1 and q(1+r)>5/2. The generalized (r, q) distribution function reduce back to the
kappa distribution function if r=0 and q= k+1 and also to the Maxwellian if q→ ∞ and r= 0. If
we fix the value of q and increase the value of r then the contribution of high-energy particle
reduces but the shoulders in the distribution function increase. The same situation also occurs
increase the value of q and keepimg fix the value of r.
We adopt this distribution function because it give a better data fit to the emperical data,
especially when there are shoulder in the profile of distribution function along with a high-energy
tail.
Applying kappa and generalized (r,q) distribution function with a real valued spectral
indices k and (r, q), we determine the disperssion relation for some electrostatic mode in cometry
plasma.
The real and imaginary part of the dielectric response function D(k, w) for these modes
are calculated and then compared with those of the Maxwellian distribution.
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Observations of drifting hole structures in radiation belt electrons induced by EMIC waves
S. Nakamura, Y. Miyoshi, K. Shiokawa, T. Hori, S. Imajo (ISEE, Nagoya Univ.), T. Mitani, T.
Takashima, I. Shinohara(ISAS/JAXA), Y. Omura, A. Matsuoka (Kyoto University)

We present observations of drifting hole structures in radiation belt electrons. The Arasesatellite and Van Allen Probes often detect fine structures in energy spectra of particle fluxes. We
examined time variations of energetic electron fluxes normalized by their averaged fluxes overthe previous 10 minutes. The flux variation shows 1-min scale depressions with clear energy
dispersion, which appear only in the relativistic energy ranges (500 keV - a few MeV) and small
pitch angles. We find that these “drifting hole structures” are frequently observed with EMIC
waves in space or around the ionospheric footprint of a satellite. The energy range and the pitchangle dependency of drifting hole is consistent with nonlinear cyclotron resonances with EMIC
waves. These observational characteristics suggest that EMIC waves cause a strong pitch-angle
scattering, leading to a sharp loss of small pitch-angle electrons. We show some examples ofsimultaneous observations of drifting hole structures and EMIC waves observed by the Arasesatellite and Van Allen Probes, and compare the results with nonlinear resonance theory anddrift periods of relativistic electrons.

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Statistical analysis of spatial distribution of wave spectra observed by PWE/OFA on board theArase
K. Nakashima (Kanazawa Univ.), Y. Kasahara (Kanazawa Univ.), S. Matsuda (ISAS/JAXA), and
A. Matsuoka (Kyoto Univ.)

The Arase satellite was launched in December, 2016 to achieve comprehensive
observations of plasma/particles, fields, and waves. The Plasma Wave Experiment (PWE) is oneof scientific instruments aboard the Arase, and it measures electric field from DC to 10 MHz andmagnetic field from a few Hz to 100 kHz (Kasahara et al., 2018). The OFA (onboard frequency
analyzer) is one of the receivers of the PWE and it continuously measures electric and magnetic
wave spectra in the frequency range from 64 Hz to 20 kHz (Matsuda et al., 2018). This frequency
range is crucial for the plasma wave observation because chorus waves, magnetospheric hiss,lightning whistlers and magnetosonic waves are detected, with a time resolution of 1 second as
a nominal operation mode.
In the present paper, we statistically analyzed the data from OFA in order to clarify thespatial distribution of the electric and magnetic field intensity of the typical emissions observedin the inner magnetosphere. First we compared our result with the previous statistical work
which was done using the spectrum data from the EMFISIS aboard Van Allen Probes (e.g.
Malaspia et al., 2017). Furthermore, we examined the spatial distribution of the wave activities
in the off-equatorial region, as the inclination of the Arase is 31 degrees which is much larger
than the ones of Van Allen Probes (~10 degrees). In the presentation, we will report the global
distribution of various kinds of plasma waves as a function of magnetic latitude, magnetic local
time and L-value.
Kasahara et al., Earth Planets Space, 2018.
Matsuda et al., Earth Planets Space, 2018.
Malaspia et al., J. Geophys. Res., 2017.

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Study of ionospheric plasma dynamics at sub-auroral latitudes using the SuperDARN radars
N. Nishitani (ISEE, Nagoya University)

The sub-auroral ionosphere is the region equatorward of the auroral precipitation region.
Owing to the effect of the polarization electric field in the presence of sub-auroral plasma density
depletion region, a wide variety of phenomena such as intense plasma flows denoted as SubAuroral Polarization Streams (SAPS), as well as their wave variations (SAPS wave variations:
SAPSWS) due to plasma instabilities, are observed. In addition, there are also phenomena
related to the dynamical interactions between the ionosphere and the neutral atmosphere,leading to Traveling Ionospheric Disturbances (TIDs), although they are not limited to the subauroral ionosphere. Since these phenomena contain both temporal and spatial variations, twodimensional observations with high temporal resolution such as mid-latitude Super Dual Auroral
Radar Network (SuperDARN) are crucial for studying them. In this lecture, a brief introductionof the (mid-latitude) SuperDARN, and recent progress of understanding the plasma dynamics inthe sub-auroral ionosphere, will be presented.

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A statistical investigation of magnetospheric and Ionospheric effects on EMIC wave propagation
Sung-Jun Noh (CSTR, NJIT), Hyomin Kim (CSTR, NJIT), Marc Lessard (UNH), MarkEngebretson (Augsburg University), Eun-Hwa Kim (PPPL, Princeton University), Viacheslav
Pilipenko (SPACE Research Institute RAS), Robert Redmon (NCEI, NOAA)Electromagnetic ion cyclotron (EMIC) waves are known to play an important role in
inner magnetospheric dynamics. EMIC waves are generated with L-mode polarization near themagnetic equator where the intensity of the magnetic field is minimum. The generated EMIC
waves propagate along the background magnetic field and can reach the ground. We investigatedpropagation characteristics of EMIC waves using data from a space-ground conjugate pair: aground magnetometer at Sanikiluaq, Canada (56.32°N, 280.86°E) located at a geomagnetic
footprint of the GOES 13 spacecraft (at a geosynchronous orbit, 285°E). This study focuses on
two observational aspects. First, we surveyed EMIC waves observed by GOES 13 to examine
whether the waves were observed both in space and on the ground simultaneously. The wave
properties and geomagnetic conditions were then investigated to address which factors mainly
affect the conjugacy of the EMIC wave. Second, using the simultaneously observed wave events,
we explored the higher frequency (f > 0.5Hz) wave filtering effect related to the ionospheric effect.

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Field-aligned Low-energy Ion Flux Enhancements of H+ and O+ in the Inner Magnetosphere
Observed by Arase
M. Nosé (ISEE, Nagoya University), A. Matsuoka (Kyoto University), Y. Miyoshi (Nagoya
University), K. Asamura (ISAS/JAXA), T. Hori (Nagoya University), M. Teramoto (Kyushu
Institute of Technology), I. Shinohara (ISAS/JAXA), and M. Hirahara (Nagoya University)

The present study examines the low-energy ion flux variations observed by the Arasesatellite in the inner magnetosphere. From the magnetic field and ion flux data obtained by thefluxgate magnetometer (MGF) and the low-energy particle experiments–ion mass analyzer(LEPi) onboard Arase, we find 55 events of the low-energy O+ ion flux enhancement accompaniedwith magnetic field dipolarization in the periods of April 1–October 31, 2017 and July 1, 2018–
January 31, 2019. The low-energy O+ flux enhancements (1) start a few minutes after the
dipolarization onset, (2) have energy-dispersed signatures with decreasing energy from a few keVdown to ~10 eV, (3) can be observed in both storm and non-storm periods, (4) have a field-aligned
distribution (pitch angle ~ 0 deg below the equator and pitch angle ~ 180 deg above the equator),and (5) increase the O+ density and the O+/H+ density ratio by ~8 times and ~3 times,
respectively. We perform numerical simulations to trace ion trajectories backward and forward
in time from the Arase positions. From the backward tracing results, we find that the low-energy
field-aligned ions observed in the inner magnetosphere by Arase are coming from the upper
ionosphere at altitude around 300–2,500 km after acceleration in the perpendicular direction.
The ion acceleration appears to be mass-dependent and take place immediately after the onsetof dipolarization. The forward tracing reveals that both H+ and O+ ions drift eastward and reachthe dawn-to-morning sector without being lost in the ionosphere, when the pitch angle scattering
effect is considered near the equatorial plane. This result suggests that these low-energy fieldaligned ions can contribute to formation of the warm plasma cloak and the oxygen torus.

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Energetic Electron Precipitations Showing ULF Modulation of VLF/LF Transmitter Signals
H. Ohya, T. Miyashita, K. Tanaka (Chiba University), F. Tsuchiya (PPARC, Tohoku University),
M. Ozaki (Kanazawa University), Y. Miyoshi, K. Shiokawa, N. Nishitani, T. Hori (ISEE, Nagoya
University), M. Teramoto (Kyushu Institute of Technology), M. Connors (Athabasca University),
S. G. Shepherd (Dartmouth College), and H. Nakata (Chiba University)

Ultra low frequency (ULF) modulation of energetic electron precipitations has been
observed by satellites, GPS-total electron content (TEC), riometers and X-ray [e.g., Brito et al.,2012]. However, there are few reports for the ULF modulation of the D-region ionosphere using
very low frequency (VLF)/low frequency (LF) transmitter signals which are useful probe toobserve &amp;gt;100keV electron precipitations. In this study, we investigate the D-region
signatures of the modulation due to the ULF waves using a network of VLF/LF transmitter
signals in North America. The transmitter signals from NLK (USA, 24.8 kHz, L = 2.88), NDK(USA, 25.2 kHz, L = 2.98) and WWVB (USA, 60.0 kHz, L = 2.26) were observed by a receiver at
ATH (Athabasca, Canada, L = 4.31). We show oscillations in intensities and phases on the NDKATH and WWVB-ATH paths with periods of 3-6 minutes during a small substorm of 05:25-05:50
UT (22:25-22:50 LT) on 4 June, 2017, and 05:00-05:30 UT on 5 May, 2011 (geomagnetically quietday). As for the event of 2017, the ground-based H-component magnetic field variations andDoppler velocity observed by the SuperDARN (Super Dual Auroral Radar Network) HF (highfrequency, 8-20 MHz here) radars showed the same periodic changes as seen in the VLF/LF
oscillations. Based on ground-based magnetic observations, there were Pi2 pulsations with thesame periods with the VLF/LF oscillations both at high- and low-latitudes. On the other hand,rising tone chorus emissions were observed at ATHA in the frequency range of 4.5-6.5 kHz. Using
Tsyganenko 2001 and 2004 magnetic field models, half of the electron gyrofrequency at themagnetic equator was estimated to be ~4 kHz. If the observed rising-tone emissions were thelower band chorus waves excited at the magnetic equator, the source region was at a lower Lshell than ATHA, where half of the electron gyrofrequency was just above 6.5 kHz and the chorus
waves propagated obliquely to the field line and reached the outer L-shell. Such an obliquely
propagating whistler-mode wave could cause resonant electron pitch angle scattering andprecipitation of energetic electrons into the atmosphere. As for another event of 2011, there weresimilar oscillations in the VLF/LF intensities and phases on the NDK-ATH and WWVB-ATH
paths with periods of 4-6 minutes. During the oscillations, variations in the Doppler velocity
observed by the SuperDARN were detected around the VLF/LF paths. In this presentation, we
will discuss the cause of these VLF/LF oscillations.

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Results from a 3-D electron density model developed from COSMIC radio occultation data using
artificial neural networks
Daniel Okoh (CAR-NASRDA)

A 3-D electron density model is developed from COSMIC radio occultation electron
density profiles. Motivation for this work is based on the fact that the COSMIC radio occultationelectron density profiles usually smear over wide range latitudes/longitudes, and so they are notprecise representations of vertical electron density profiles for particular locations as often
approximated in many research. Artificial neural networks are trained to learn 3-D ionosphericelectron density distribution from numerous COSMIC radio occultation profiles. From thedeveloped model, vertical electron density profiles that compare well with ionosonde verticalprofiles are derived. Additional advantages for the developed model are that the COSMIC profiles
used for the model development include topside measurements that reach about 800 km, andthey also have good spatial coverage. Results from the developed model also enhance ourunderstanding of phenomena like the equatorial ionization anomaly in 3-D space.

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Estimation of ionospheric critical plasma frequencies from GNSS-TEC measurements using
artificial neural networks
Vivian Otugo, Daniel Okoh, Charity Okujagu, Sylvester Onwuneme1, Babatunde Rabiu, Jean
Uwamahoro, John Bosco Habarulema, Mpho Tshisaphungo, Nicholas Ssessanga

This paper describes a new neural network-based approach to estimate ionosphericcritical plasma frequencies (f0F2) from GNSS-VTEC (Global Navigation Satellite System –Vertical Total Electron Content) measurements. The motivation for this work is to provide amethod that is realistic and accurate for using GNSS receivers (which are far more commonly
available than ionosondes) to acquire f0F2 data. Neural networks were employed to train VTEC
and corresponding f0F2 observations respectively obtained from closely located GNSS receivers
and ionosondes in various parts of the globe. Available data from 52 pair of ionosonde-GNSS
receiver stations for the 17-year period from 2000 to 2016 were used. Results from this work
indicate that the relationship between f0F2 and TEC is mostly affected by the seasons, followedby the level of solar activity, and then the local time. Geomagnetic activity was the leastsignificant of the factors investigated. The relationship betweenf0F2 and TEC was also shown to
exhibit spatial variation; the variation is less conspicuous for closely located stations. The results
also show that there is a good correlation between the f0F2 and TEC parameters. The f0F2/TEC
ratio was generally observed to be lower during enhanced ionospheric ionizations in the day time,and higher during reduced ionospheric ionizations in the nights and early mornings. The analysis
of errors show that the model developed in this work (known as the NNT2F2 model) can be used
to estimate the f0F2 from GNSS TEC measurements with accuracies of less than 1 MHz. The
new approach described in this paper to obtain f0F2 based on GNSS TEC data represents animportant contribution in space weather prediction.

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The Effect of Prompt Penetration Electric (PPE) on Total Electron Content during Intense andSuper Geomagnetic Storm Events at Low and Mid Latitude Regions
Owolabi T.P., Ariyibi E.A., Olatunbosun L.G.

This study evaluated the diurnal variations of ionospheric Total Electron Content (TEC)
and determined the dependence of TEC on geomagnetic storms during different geomagnetic
storm events at low- and mid-latitude stations with a view to understanding the effects of prompt
penetration electric (PPE) field during the identified four intense and two super geomagnetic
storm events that occurred between 2013 and 2015.
GPS data from the low-latitude and mid-latitude stations of Cotonou, Benin Republic at
Geomag Lat. 8.71°N, Long. 76.42°E and Marseille, France at Geomag Lat. 44.32°N, Long.
87.25°E for 2013, 2014 and 2015 were obtained from the GPS receiver located at the stations.
The results of the diurnal variation of TEC showed that the maximum daytime TEC
values of ~70 TECu at low latitude station of Cotonou is more than double the values of ~30
TECu at mid-latitude station of Marseille for the years considered. The intense storm event of 1
June, 2013 indicated that the percentage deviation of TEC from the mean TEC for the monthwas 11 and -20% and for Cotonou and Marseille stations respectively. Also, for the super storm
event of 17 March 2015, 26 and 67% were the percentage deviation of diurnal TEC during storm
from the monthly mean TEC for Cotonou and Marseille. The effect of PPE observed during theintense storm of 19 February 2014 revealed a gradual increase in daytime TEC value at low
latitudes and a corresponding fluctuation in TEC values of ~10 TECu at mid-latitudes.

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Event study of the M-I-T coupling in the ionospheric trough region for Kp = 0+
S. Oyama (ISEE, Nagoya U.), A. Aikio (U. Oulu), H. Vanhamäki (U. Oulu), A. Shinbori (ISEE,
Nagoya U.), M. Rietveld (EISCAT), Y. Ogawa (NIPR), M. Kellinsalmi (FMI), T. Raita (SGO, U.
Oulu), K. Shiokawa (ISEE, Nagoya U.), I. Virtanen (U. Oulu), L. Cai (KTH), A. Workayehu (U.
Oulu), M. Pedersen (U. Oulu), K. Kauristie (FMI), B. Kozelov (PGI) and A. Demekhov (PGI)

Ionospheric trough is a low plasma-density area occasionally appeared at subauroral
latitudes, typically seen for period of geomagnetic disturbances. On 20 February 2018, a zonallyelongated ionospheric trough was developed from Fennoscandia to North America. Of notableinterest was the geomagnetic activity, which was considerably quiet level as represented by Kp
index of 0+ for the time interval interested in this study. The ionospheric trough was located at70-71 deg N and the main auroral oval stayed at 74-76 deg N in the Fennoscandia sector. A minor
but obvious auroral enhancement occurred at about 18:35 UT (~21 MLT) near Svalbard
archipelago. We call this “pseudo-breakup” in this study. Coinciding with the pseudo-breakup, a
red arc emerged from a breakup auroral blob appeared at the equator side edge of the auroral
oval. Swarm measurements show a notable enhancement of the electron temperature at thetrough minimum, which is the location of the red arc. This experimental evidence suggests thatthe event has captured a moment of the SAR-arc birth, which is usually masked by brightdynamical aurorae at the substorm expansion phase. Looking at the dynamics in the ionosphereand the thermosphere, westward turning of the ionospheric ion velocity from +200 m/s to -200
m/s was detected with the Dynasonde at Tromsoe, Norway (69.6 deg N), that is, in the ionospherictrough or slightly its equatorward side. At the same time, the collocated Fabry-Perot
interferometer (FPI) also detected westward acceleration of the wind starting from +100 m/s(positive eastward) but without change its direction. The anti-directional velocities lasted for 19
min, and the energy flow for that period may have been from the ionosphere to themagnetosphere. Furthermore, Poynting flux derived from the Swarm measurements revealed
upward energy flow at the trough minimum and Tromsoe latitude. These spatiotemporal sporadic
and local phenomena coinciding with the pseudo breakup may be signatures induced bytransitional processes in the M-I-T coupled system during the substorm expansion phase.

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Flash-type auroral model using chorus-ray tracing analysis
Mitsunori Ozaki, Tomohiro Inoue, Yoshimasa Tanaka, Satoshi Yagitani, Yoshiya Kasahara,Kazuo Shiokawa, Yoshizumi Miyoshi, Kousuke Imamura, Keisuke Hosokawa, Shin-ichiro Oyama,
Ryuho Kataoka, Yusuke Ebihara, Yasunobu Ogawa, and Akira Kadokura

Flash-type aurora is a rapid (less than the duration of 1 s) auroral phenomenon driven
by a single discrete chorus element. Flash aurora is useful for understanding the spatial-time
evolution of wave-particle interaction regions in the magnetosphere. We simulate flash auroral
morphology using chorus-ray tracing analysis to evaluate the effects of wave propagation to theauroral morphology in subauroral latitudes. The initial ray paths were injected at the magnetic
equator from a point source. Then, resonant particles traced the magnetic field lines from thechorus ray paths in the magnetosphere to the ionosphere, and estimated column emissions using
volume emission rate for N2 1st positive bands. The calculated column emissions for flash aurora
showed a clear spatial dependence with respect to the latitudes. In this presentation, we will
present the calculation model of flash aurora using chorus-ray tracing and volume emission rateand discuss the effects of chorus wave propagation on the flash auroral morphology (spatial size,
anistropic spatial evolution etc.) in detail.

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Extracting Plasmaspheric Contributions from Total Electron Content using Digisonde, COSMIC,
and GPS Observations and Model ComparisonsSampad Kumar Panda (KLEF, India), Haris Haralambous (Frederick University, Cyprus), Mefe
Moses (Ahmadu Bello University, Nigeria)

The ionosphere is defined as the layer of the Earth&amp;#39;s atmosphere between 60
to 1,000 km that is ionized predominantly by solar radiation, resulting in the generation of freeelectrons and ions. Free electrons in the ionosphere and its overhead plasmasphere constitute aseriouschallenge

to

space-basedtrans-ionosphericradio

propagationandsatellite

communication by introducing delays in the signals and thereby degrading the positioning
accuracy. It has been a challenging task to develop a reliable model for estimating the accurate
amount of delays introduced with the traversing radio signal in the plasmasphere and ionosphere.
A realistic representation of bottomside (BTEC), topside (TTEC) total electron content, andplasmasphere electron content (PEC) is a crucial task for the accurate representation ofionosphere and plasmasphere model configurations. This is because the complete altitudinal
electron density profile specification is restricted by a synchronised adequacy of data from groundor space-based instruments. In this article, we present sensible assimilation of peak parametersin the topside profiles from the FormoSat-3/COSMIC ionospheric occultations with the autoscaled bottomside profiles from 39 global Digisonde rather than peak to topside extrapolation.
Under a strict space-time collocation criterion, the integral electron content from the assimilated
electron density profiles along with GPS derived TEC demonstrates altitude dependent
contributions. The corresponding estimations from the empirical ionospheric and plasmasphericmodels (IRI-2016, NeQuick-2, and IRI-Plas 2017) are also assessed to realize their discrepancies
with respect to the observed ionospheric parameters. The statistical comparison metrics show
relatively closer ionospheric electron content estimates from IRI with the assimilated results,
followed by NeQuick and IRI-Plas models, with the last two models apparently showing an
opposite behavior between bottomside and topside electron content discrepancies. However,
although the TEC estimations reveal a relatively superior performance of IRI-Plas withsuccessive proficiency of NeQuick and IRI models, the retrieved PEC data does not evident any
clear statistical metrics and dictates further investigation. Nevertheless, this assimilation work
leads towards improving the altitudinal representation of ionospheric models, particularly in thecontext of real-time representation of topside, bottomside, and plasmaspheric electron content
through a reconstruction of the complete electron density profile.

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Comparison of the ionospheric F2 peak height between digisonde measurements and IRI-2016
predictions over Irkutsk, Russia
Nilesh C. Patel (Bhagwan Mahavir College of Science and Technology, Surat-395007, Gujarat,
India), Kamlesh N. Pathak, Sheetal P. Karia (Department of Physics, S. V. National Institute ofTechnology, Surat-395007, Gujarat, India.)

The International Reference Ionosphere (IRI) is the most commonly used community
empirical model. The latest version IRI-2016 provides three options for the F2 peak height hmF2:
AMTB 2013 (AMT), SHU-2015 (SHU), and BSE-1979 (BSE). In this paper, we used the hmF2
data derived by the digisonde at Irkutsk, Russia (52.5°N, 104.3°E) ranging from one year (amoderate solar activity Year: 2012) to assess the performance of these three options in the model.
The results show that the variability of the observed hmF2 versus local time and seasons could
be reproduced similar trends by the three options. However, the SHU-2015 option performs bestat this station, followed by BSE-1979, and the AMTB2013.

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Interaction of magnetospheric Pc1 waves with the ionospheric resonators and waveguides
Pilipenko V.A. (IPE)The following topics are to be discussed:-High-latitude Pc1 emissions as observed in Arctic and Antarctic;-Filtering of magnetospheric waves upon transmission though the ionosphere;-Distant Pc1 signal propagation along the ionosphere;-Ionospheric ULF-ELF electromagnetic response to ground transmitters and lightning
discharges;-Man-made excitation of Pc1 emissions;-New stations and databases for Pc1 studies.

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EMIC wave induced proton precipitation during the 27-28 May 2017 storm: Comparison of
BATSRUS+RAM-SCB simulations with ground/space based observations
Shreedevi P.R, Yiqun Yu, Yoshizumi Miyoshi, Xingbin Tian, Chae-Woo Jun, Kazuo Shiokawa,
Vania Jordanova

Electro Magnetic Ion Cyclotron (EMIC) waves are known to initiate the ion precipitation
into the mid latitude ionosphere during geomagnetic storms. Recent studies have shown that the
EMIC wave induced ion precipitation can contribute significantly to the total energy flux
deposition into the ionosphere and severely affect the magnetosphere-ionosphere coupling. In
this study, the temporal and spatial evolution of the proton precipitation into the ionosphere andits correspondence to the EMIC wave activity in the inner magnetosphere is examined using
simulations from the BATSRUS+RAM-SCB model. During the geomagnetic storm of 27-28 May
2017, the Van Allen Probes satellite observed typical signatures of EMIC waves in the innermagnetosphere i.e., at 4 to 6 Re in the evening sector. Ground magnetometers at high latitude
stations also showed the presence of PC1/EMIC waves after 1600 UT on 27 May 2017. During
the main phase of the storm, the DMSP satellites observed enhanced proton precipitation at
locations where the ground/space based magnetic field measurements showed the presence ofenhanced EMIC wave activity. The plasma source and distributions of associated temperature
anisotropy in the equatorial plane are investigated to understand the excitation of the waves. A
comparison of the precipitating proton fluxes obtained from the simulations with the particle
measurements from the DMSP satellites show that EMIC wave scattering can account for the 30
keV proton precipitation at sub auroral latitudes. This study shows that the EMIC wave-particle
interaction plays a significant role in the spatio-temporal evolution of the ion precipitation in the
mid latitude ionosphere.

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Analysis of Relativistic Electron Fluxes in the Outer Radiation Belt during an Intense and a
Moderate Storm:S. Rathi, M.V.S. Krishna (IIT Roorkee)

We have analyzed the Radiation Belts Electrons(E~2.0 MeV) fluxes for two magnetic
storms, an intense storm from 25-Aug-2018 to 30 Aug-2018 and a moderate storm 6-Nov-2017 to
10-Nov-2017, using the Van Allen A & B-REPT and ARASE-XEP data. Both the storms result in
the increase of electron fluxes in the radiation belts. Enhancement is also observed using the
GOES 15 data.
During the Intense storm recovery phase, the electron flux increases throughout theouter belt by more than one order of magnitude, and the peak shifts inward towards lower L(Re).
A similar pattern is observed in all three satellite data. We also observed that these satellites
show the flux enhanced only in dawn and dusk region and dawn-dusk asymmetry is seen. The
flux enhancement is more in the dawn than dusk by one order of magnitude for L<5.6Re. For
REPT A & B, the dawn-dusk flux ratio increases with L<4.29Re and decreases for higher L(<6Re).
But ARASE shows an increasing dawn-dusk enhancement ratio with L(L<6Re).
The moderate storm results in order of magnitude enhancement of electrons for L<3.8Re
but a slight decrease for 3.8Re<L>3Re and the peak of outer belt flux shits slightly outward
towards high L, for both REPT and ARASE. The REPT shows enhancement in the dawn andnoon sector whereas ARASE in noon and dusk sector. A dawn-dusk flux ratio is calculated using
the REPT dawn and ARASE dusk data.
In both the storms, the dusk side flux decreases faster than the dawn side withincreasing L suggesting a faster acceleration in the dawn sector by chorus waves(local
acceleration) or the dusk losses are fast.

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Geoeffectiveness of CME Clusters
J. M. Rodriguez Gomez (Skolkovo Institute of Science and Technology (Skoltech))Rodriguez Gomez et al. 2020 shows that clusters of fast CMEs are statisticallyassociating with the disturbance storm time index at Earth. It suggests that fast CMEs occurringin clusters tend to produce larger geomagnetic storms than isolated fast CMEs. In this work, theplanetary K index were explored to find their relationship with clusters of fast CMEs duringsolar cycles 23 and 24.

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Global observation of poloidal Pc4-5 waves in the magnetosphere before and during substorm
A.V. Rubtsov (ISTP SB RAS; API ISU), O.S. Mikhailova, D.Yu. Klimushkin (ISTP SB RAS), J.
Ren, Q.G. Zong (SESS PKU)

We present a preliminary analysis of global observation of the first harmonic poloidal
Pc4-5 waves observed on the dayside of the magnetosphere. Waves were observed for ~15 hours
by widely spaced satellites of three missions (Van Allen Probes, THEMIS, GOES): 7–17 MLT and
L = 4.5–8 RE. The first appearance of the waves was ~20 minutes before the substorm injection
on the nightside (observed by GOES15) and ~30 minutes before AE index increase. Note that thesolar wind conditions were quiet and there were no magnetic storm or substorm activities within
at least 12 hours before. The combined observations demonstrate discrete frequency dependenceon L-shell and no specific azimuthal frequency distribution. The observations at the same L-shellat different time show frequency increase with time. Some oscillations in energy range 25–100
keV were observed in both ion and electron data. The azimuthal wave number were preliminary
calculated using finite gyroradius effect and equals –(20-80).
The reported study was funded by RFBR and NSFC according to the research project 2055-53009.

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On the influence of the orientation of pulsating auroral structure on associated geomagnetic
pulsations in 3±1 Hz frequency range
V. Safargaleev (PGI), T. Sergienko (IRF), K. Hosokawa (UEC), Y. Ogawa (NiPR), Y. Miyoshi,
Nagoya University, Sh-I. Oyama (ISEE, University of Oulu, NiPR), S. Kurita (RISH), R. Fujii(ROIS)

Two situations in pulsating auroras have been analyzed, in which the orientation ofpulsating quasi-arcs was different - along and across the meridian. In both cases, geomagnetic
pulsations associated with high-frequency pulsations of luminosity were more pronounced in themagnetic component perpendicular to the pulsating arc than in the component along the arc.
This makes it possible to associate geomagnetic pulsations of this frequency range with themodulation of the ionospheric current along the arc, rather than with the arrival of a modulating
wave in the ionosphere. The result should be taken into account in searching for the causes ofhigh-frequency modulation of the flux of precipitating electrons.

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Spacecraft measurements of whistler mode waves as a tool for investigation of the innermagnetosphere
Ondrej Santolik

In-situ observations of the whistler mode waves continue to play an important role in
the investigation of the inner magnetosphere. These experimental results provide us withvaluable feedback on how well the existing theories describe interactions of electromagnetic
waves with inner magnetospheric plasmas and energetic particles. Multicomponent andmultipoint measurements of recent scientific missions, such as Arase, Van Allen Probes, Themis
and Cluster, also stimulate development of novel theories and numerical simulations, especiallyconcerning nonlinear emissions of whistler mode chorus but also other types of electromagnetic
waves occurring in the inner magnetosphere. The lecture will be devoted to a review of thesemeasurements, with selected examples of results.

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Relationship between the locations of the mid-latitude trough and plasmapause using GNSSTEC and Arase satellite observation data
A. Shinbori, Y. Otsuka (ISEE, Nagoya University, T. Tsugawa, M. Nishioka (NICT), A. Kumamoto,
F. Tsuchiya (PPARC, Tohoku University), S. Matsuda (ISAS/JAXA), Y. Kasahara (Kanazawa
University), and A. Matsuoka (WDC, Kyoto University)

Relationship between the locations of the mid-latitude trough minimum in theionosphere and plasmapause in the inner magnetosphere has been statistically investigatedusing global navigation satellite system (GNSS) – total electron content (TEC) and electron
density data obtained from the Arase satellite from March 23 2017 to May 31 2020. In thisanalysis, we identify the mid-latitude trough minimum as a minimum value of GNSS-TEC at
sub-auroral and mid-latitude regions, and determine the plasmapause as an electron density
decrease by a factor of 5 or more within L <0.5 in the inner magnetosphere. As a result, theplasmapause does not always coincide with the mid-latitude trough minimum in all magnetic
local time (MLT) sectors under all geomagnetic conditions. During the geomagnetically quiet
periods, the mid-latitude trough minimum is located at higher and lower geomagnetic latitudes(GMLAT) of the plasmapause in the MLT ranges of 5–21 and 21-5 h, respectively. This implies
that both the features could not be on the same magnetic field line. On the other hand, during
the storm main phase, the mid-latitude trough minimum and plasmapause move toward a lowlatitude region with day-night and dawn-dusk asymmetries and the correlation becomes highest,
compared with that under other geomagnetic conditions. Both the features are located at almost
the near GMLAT in the afternoon-midnight sectors. This suggests that the formation of the midlatitude trough and erosion of the plasmasphere occur on almost the near magnetic field line due
to an enhanced sub-auroral polarization stream during the storm main phase.

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Ground-based observation of aurora and plasma waves for investigation of the innermagnetosphere
Kazuo Shiokawa (ISEE, Nagoya University)

Ground-based instruments take important role for measurements of plasma dynamics
in the inner magnetosphere. The plasma and waves tend to move along geomagnetic filed lines
and make it possible to monitor them from the ground. Ground-based stations at subauroral
latitudes can monitor various phenomena occurring in the inner magnetosphere continuously ata fixed point. Aurora and airglow imagers and multi-point GNSS receivers can provide twodimensional distribution of plasma structures in the ionosphere. In this lecture, we review
various ground-based instruments with their advantages for investigation of the plasma
dynamics in the inner magnetosphere.

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Arase observation of the source region of auroral arcs and diffuse auroras in the innermagnetosphere
K. Shiokawa (ISEE, Nagoya Univ.), M. Nose (ISEE, Nagoya Univ.), S. Imajo (ISEE, Nagoya Univ.),
Y. Tanaka (NIPR), Y. Miyoshi (ISEE, Nagoya Univ.), K. Hosokawa (Univ. of ElectroCommunications), M. Connors (Athabasca Univ.), M. Engebretson (Augusburg Univ.), Y. Kazama(NCKU), S.-Y. Wang (NCKU), S. W. Y. Tam (NCKU), Tzu-Fang Chang (NCKU), Bo-Jhou Wang
(Academia Sinica), K. Asamura (ISAS/JAXA), S. Kasahara (Univ. Tokyo), S. Yokota (Osaka Univ.),
T. Hori (ISEE, Nagoya Univ.), K. Keika (Univ. Tokyo), Y. Kasaba (Tohoku Univ.), M. Shoji (ISEE,
Nagoya Univ.), Y. Kasahara (Kanazawa Univ.), A. Matsuoka (Kyoto Univ.) and I. Shinohara(ISAS/JAXA)

Auroral arcs and diffuse auroras are common phenomena at high latitudes, thoughcharacteristics of their source plasma and fields have not been well understood.

In thispresentation, we report the first observation of fields and particles including their pitch-angle
distributions in the source region of auroral arcs and diffuse auroras, using data from the Arasesatellite at L~6.0-6.5, based on the report by Shiokawa et al. [2020]. The auroral arcs appeared
and expanded both poleward and equatorward at local midnight from ~0308 UT on 11 September
2018 at Nain (magnetic latitude: 66o), Canada, during the expansion phase of a substorm, while
diffuse auroras covered the whole sky after 0348 UT. The top part of auroral arcs wascharacterized by purple/blue emissions. Bi-directional field-aligned electrons with structured
energy-time spectra were observed in the source region of auroral arcs, while source electrons
became isotropic and less structured in the diffuse auroral region afterwards. We suggest thatstructured bi-directional electrons at energies below a few keV were caused by upward fieldaligned potential differences (upward electric field along geomagnetic field) reaching highaltitudes (~30,000 km) above Arase.

The bi-directional electrons above a few keV were probably

caused by Fermi acceleration associated with the observed field dipolarization. Strong electricfield fluctuations and earthward Poynting flux were observed at the arc crossing, and areprobably also caused by the field dipolarization.

The ions showed time-pitch-angle dispersion

caused by mirror reflection. These results indicate a clear contrast between auroral arcs anddiffuse auroras in terms of source plasma and fields, and generation mechanisms of auroral arcs
in the inner magnetosphere.
Reference: Shiokawa, K. et al., Arase observation of the source region of auroral arcs and diffuse
auroras in the inner magnetosphere. Journal of Geophysical Research: Space Physics, 125,e2019JA027310. https://doi.org/10.1029/2019JA027310, 2020.

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Statistical analyses on low energy ion heating by electromagnetic ion cyclotron waves via waveparticle interaction analyses: Arase observations

M. Shoji, Y. Miyoshi (ISEE, Nagoya University), L. M. Kistler (ISEE, Nagoya University,
University of New Hampshire), K. Asamura (ISAS), Y. Kasaba (Tohoku University), A. Matsuoka(Kyoto University), Y. Kasahara (Kanazawa University), S. Matsuda (ISAS), F. Tsuchiya, A.
Kumamoto (Tohoku University)

Electromagnetic ion cyclotron (EMIC) waves are generated through the cyclotron waveparticle interaction, affecting the plasma environment in the magnetosphere. Heating of the ionsby EMIC waves in the inner magnetosphere has also been investigated by spacecraft
observations by comparing the pitch angle distribution of the ions and the wave emissions. We
can directly detect the energy transfer between the plasma waves and the ions via the waveparticle interaction analysis (WPIA) method which calculates the inner product between the
wave electric fields and the ion velocities. We adapt the WPIA method to the Arase spacecraft
data and investigate the spatial distribution of the positive qV∙E region in the innermagnetosphere. From March 21st 2017 to September 27th 2019, we select 149 EMIC wave events
associating flux enhancement between 10 eV to 100 eV which are suitable dataset for the WPIA
method observed by PWE/EFD, MGF, and LEP-i onboard the Arase satellite. The peaks of the
proton heating appear in the dayside and post noon regions. Typical EMIC waves inside theplasma plume contribute to the peak in the afternoon sector in both quiet and active times. On
the other hand, in the dayside region, the proton heating takes place during quiet times. It
suggests that the protons in the region are energized by the EMIC waves generated by the EMIC
waves generated by compression of the magnetic field. We also discuss the heavy ion heating.

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Study of the polarization jet using satellite data
A.A. Sinevich, A.A. Chernyshov, D.V. Chugunin (IKI RAS)

The subauroral region of the ionosphere is currently a hot topic for research, since manyof the phenomena occurring in it are not fully understood. One of such phenomena is apolarization jet. A polarization jet is a narrow jet of fast ionic drifts to the west near the projectionof the plasmapause at the heights of the F-layer ionosphere, which appears during increased
geomagnetic activity. The mechanism of the formation of a polarization jet, as well as the
structure of small-scale irregularities in the parameters of the ionosphere within it are open
questions. To study small-scale plasma density inhomogeneities, devices are needed thatmeasure plasma characteristics at a high frequency. Until recently, the average frequency of
instrument measurements on satellites was 2–5 Hz, until the NorSat-1 satellite was launched,equipped with 4 Langmuir probes and capable of measuring the parameters of the ionospherewith a frequency of up to 1 kHz. The presented work is to study small-scale polarization jet
inhomogeneities using satellite data.

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Statistical (ANOVA) analysis of variations in Solar and Geomagnetic Parameters for Solar Cycle
24
D.K. Sondhiya
School of Sciences, SAGE University, Bhopal, India

Analysis of plages and spots on the photosphere is very important to study the magnetic
field of the sun and dynamic processes associated with Sun and other stars. It also influences themagnetic field of earth and other planets. Sunspot numbers are considering as prime indicatorof solar activity prominent feature of 11 year cycle known Schwabe cycle. Schwabe cycle shows
the long term variation in interplanetary and geomagnetic parameters. In the present work, wehave analyzed the sunspot number and their interrelationship with other solar activity
parameters using statistical ANOVA method. The observed irregularities in the relationshipbetween sunspot number and other solar activity parameter have been discussed. Also develop asuitable regression based model to explain the various long-term characteristics of solar activity.
Keywords: Schwabe cycle, ANOVA, Interplanetary magnetic field, Dst Index

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Simultaneous observations of a low-altitude ion upflow by the EISCAT radar and molecular ionsin the ring current by the Arase (ERG) satellite
M. Takada (Graduate School of Science, Tokyo University), K. Seki (Graduate School of Science,
Tokyo University), Y. Ogawa (National Institute of Polar Research), K. Keika (Graduate Schoolof Science, Tokyo University), S. Kasahara (Graduate School of Science, Tokyo University), S.
Yokota (Graduate School of Science, Osaka University), T. Hori (Institute for Space-EarthEnvironmental Research, Nagoya University), K. Asamura (Institute of Space and Astronautical
Science, Japan Aerospace Exploration Agency), Y. Miyoshi (Institute for Space-EarthEnvironmental Research, Nagoya University), I. Shinohara (Institute of Space and Astronautical
Science, Japan Aerospace Exploration Agency)
Molecular ions (O2+/NO+/N2+) originating from the ionosphere have been observed in
the magnetosphere during the magnetic storms [e.g., Klecker et al., 1986; Christon et al., 1994]
and also recently observed by Arase satellite even during weak geomagnetic disturbance periods[Seki et al., 2019]. It suggests that the molecular ions are commonly supplied from the ionosphere.
However, it is not revealed how these molecular ions are transported from the low-altitude(&amp;lt;300 km) ionosphere where molecular ions usually exist. These molecular ions are
considered to be transported upward by some heating mechanisms such as ion frictional heating,particle precipitations and local plasma instabilities. However, previous observations indicatethat those mechanisms are not efficient enough to transport molecular ions by overcoming loss
due to the dissociative recombination [Peterson et al., 1994].
In this study, we aim at quantitative assessment of the ion upflow process for themolecular ions from the low-altitude ionosphere based on the simultaneous observations by the
EISCAT radar and the Arase (ERG) satellite on September 8, 2017. During the magnetic storm
started from September 7, 2017, the Arase (ERG) satellite observed molecular ions(O2+/NO+/N2+) in the ring current. The EISCAT radar simultaneously observed the ion upflow(~50-150 m/s) in the low-altitude (250-350 km) ionosphere together with strong ion heating(&amp;gt;2000 K) during the main phase around the second Dst minimum of the storm. The
convective electric field derived from the electron heating observed by EISCAT around 110 km
altitude was also enhanced by a factor of 2. The observations suggest that the additional ion
heating at the low-altitude ionosphere helped to cause the fast upflow and transport molecularions upward. We also estimated flux decrease of molecular ions (O2+/NO+) from 280 to 350 km
altitudes due to the dissociative recombination. It was about two orders of magnitude without
any production processes. But we could not directory compare with the molecular ions observed
by Arase and EISCAT in this case. However, these results suggest the possibility that the lowaltitude ion upflow caused by the ion frictional heating enables molecular ions to escape to spaceagainst rapid loss by the dissociative recombination.
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Relative Contribution of ULF Waves and Whistler-mode Chorus to the Radiation Belt Variation
during the May 2017 Storm
N. Takahashi, K. Seki (Univ. Tokyo), M.-C. Fok, Y. Zheng (NASA GSFC), Y. Miyoshi (ISEE,
Nagoya Univ.), S. Kasahara, K. Keika (Univ. Tokyo), D. Hartley (Univ. Iowa), Y. Kasahara(Kanazawa Univ.), Y. Kasaba (Tohoku Univ.), N. Higashio (JAXA), A. Matsuoka (Kyoto Univ.), S.
Yokota (Osaka Univ.), T. Hori, M. Shoji, S. Nakamura, S. Imajo (ISEE, Nagoya Univ.), I.
Shinohara (ISAS, JAXA)The Earth’s radiation belt exhibits a dramatic variation during the active condition of
the magnetosphere such as magnetic storms. The dynamic variation of the radiation belt is, inpart, contributed by various wave-particle interactions, including: (1) the radial diffusion ofelectrons driven by ultra-low-frequency (ULF) waves in Pc5 frequency ranges (2-7 mHz), and (2)the local acceleration caused by wave-particle interactions between whistler-mode chorus andradiation belt particles. Over the past decade, multi-point observations and numericalsimulations have separately demonstrated evidence for the contribution of ULF waves andwhistler-mode chorus to the relativistic electron flux enhancement. However, comparison of thecontribution of ULF waves and whistler-mode chorus has not been extensively studied yet. To
our best knowledge, there are few papers that have demonstrated the global picture of wave
contribution to the total radiation belt content with relative comparison.
We investigate when and where ultra-low-frequency (ULF) waves and whistler-mode
chorus contribute to the net flux of relativistic electrons during the May 2017 storm. During theearly recovery phase, ULF waves mainly contribute to the global enhancement of relativistic
electron flux in the dusk. In the nightside, both waves are related to the flux variation. During
the late recovery phase, both Van Allen Probe (RBSP)-B and Arase show that whistler-mode
chorus contributes to the flux enhancement confined in L-value. The Comprehensive Ring
Current Model (CRCM) coupled with Block-Adaptive-Tree Solar-Wind Roe-Type Upwind Scheme(BATS-R-US) simulation qualitatively reproduces the global evolution of ULF waves. The
estimated region where the anisotropy of hot electrons is large shifts toward dusk during therecovery phase. In addition, the estimated magnetic field curvature at dayside is small during
the recovery phase. We also investigate what controls the wave evolution. Both observations andsimulation suggest that observed ULF waves are excited by the enhancement of the solar winddynamic pressure. Observations also indicate that whistler-mode chorus in the nightside ispredominantly excited by the anisotropic distribution of hot electrons, whereas dayside chorus isaffected by the magnetic field line configuration. Estimated spatial distributions of electron
anisotropy and magnetic field curvature give an explanation for observational results thatenhanced whistler-mode chorus exists in the dusk, which is far from the ordinary location of wave
generation.
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A Direction finding Method Considering Different Signal to Noise Ratio among Sensors
Y. Tanaka, Y. Kasahara (Kanazawa University), and M. Ota (Toyama Prefectural University)

The analysis of plasma waves obtained from in-situ observations by scientific satellites
is an effective method to investigate the plasma environment in the inner magnetosphere.
Direction finding of plasma waves provides important information for understanding not only
local plasma environment but also the global features of the inner magnetosphere.
One of the methods about direction finding is the wave distribution function (WDF)
method, which derives directional distribution of wave energy density using a priori informationsuch as the propagation mode, plasma density and geomagnetic field intensity. The WDF method
is attracting attention as a method to realize detailed propagation analysis of plasma waves, as
this method can be applied when multiple waves are superimposed or the wave source is widelydistributed.
Among the solutions of the WDF methods, the Markov random field model (MRF) is
known as a robust model that provides accurate estimation results even in noisy environments.
The MRF takes into account an integration kernel corresponding to white noise (noise integration
kernel) used for the estimation, which improves the robustness. The noise integration kernel isconventionally designed under the assumption that the noise levels of all electromagnetic fieldsensors are equal. However, the noise levels of the electromagnetic field sensors on board ascientific satellite often change due to the degradation of the sensors during long-term operation
period of the instruments.
In this study, the estimation accuracy of MRF with different noise levels ofelectromagnetic field sensors was verified by simulation. We also propose a design method of thenoise integration kernel to improve the estimation accuracy and verify its effectiveness.

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Statistical survey of Energetic Electron Precipitation events using coordinate observations from
Arase and ground Riometer network
Neethal Thomas (SGO,University of Oulu), Antti Kero (SGO,University of Oulu), Miikka Hyötylä
(SGO), Kazuo Shiokawa (ISEE,Nagoya University), Yoshizumi Miyoshi (ISEE,Nagoya
University), Yoshiya Kasahara (Kanazawa University), Satoshi Kasahara (The University ofTokyo), Shoichiro Yokota (Osaka University), Kunihiro Keika (The University of Tokyo), Tomo
Hori (The University of Tokyo), Shiang-Yu Wang (Academia Sinica Institute of Astronomy andAstrophysics), Yoichi Kazama (Academia Sinica Institute of Astronomy and Astrophysics), C-W.
Jun (ISEE,Nagoya University), Sunny Wing-Yee Tam (National Cheng Kung University), TzuFang Chang (National Cheng Kung University), Bo-Jhou Wang (Academia Sinica Institute of
Astronomy and Astrophysics), Kazushi Asamura (ISAS), Ayako Matsuoka (JAXA), and Iku
Shinohara (JAXA)The energetic electrons present in the radiation belt and that injected into the nightside
magnetosphere in association with substorm intervals are known to accelerate and precipitate
into the Earth’s atmosphere under favorable conditions. In this study, the Energetic Electron
Precipitation (EEP) events are investigated using coordinate observations from the groundriometer network and inner-magnetospheric satellite mission, Arase. We have analyzed one anda half years of data between March 2017 to September 2018. EEP events are firstly identified
using the Finnish ground riometer network (located between Geographic Latitude: 60°N to 77°N
and Geographic longitude: 15°E to 28°E) by estimating the cosmic noise absorption (CNA). The
Arase conjunctions with the ground riometer stations during the study period are considered.
Based

on

the

riometerabsorption

values,theeventsarecategorized

as

CNA

(absorption&amp;gt;0.5 dB) and non-CNA (absorption&amp;lt;0.5 dB) periods. The riometer
observations are then compared with the comprehensive dataset of plasma waves and flux
observations from Arase satellite. The relation between the plasma flux/waves observed at thesatellite with the ground riometer absorptions are investigated by performing statistical analysisof the spectra measured by the Arase during CNA and non-CNA periods separately. During CNA
period, the plasma flux/wave measured by Arase is found to be highly correlating with theriometer absorption in certain parts (energy/frequency range) of the spectra. Our study provides
an estimate of the statistical dependence of the plasma flux observations at satellites with theground reality of actual precipitating electron flux and also the contribution of plasma waves on
it. The statistical results along with representative events will be presented and discussed.

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Spatio-temporal characteristics of the precipitating electron energy of pulsating aurora derived
from multi-wavelength optical measurements
K. Toyama, S. Kurita(Kyoto University), Y, Miyoshi (ISEE,Nagoya University), K. Hosokawa(University of Electro-Communications), Y. Ogawa (National Institute of Polar Research), S.
Oyama (ISEE,Nagoya University), S. Nozawa (ISEE,Nagoya University), T. Kawabata(ISEE,Nagoya University), S. Saito (National Institute of Information and Communications
Technology), and Y. Ito (ISEE,Nagoya University)

Pulsating aurora (PsA) is characterized by quasi-periodic intensity modulations with aperiod of 2-20 s which is known as the main modulation. Electrostatic Cyclotron Harmonic waves
and whistler-mode waves are known to cause the pitch angle scattering of energetic electrons in
the magnetosphere. In particular, whistler-mode chorus waves play a crucial role in the pitch
angle scattering of the electrons. The lower-band chorus causes precipitation of electrons whoseenergy is greater than several keV [Miyoshi et al., 2015]. The energy of precipitating electrons
causing PsA may be estimated from ground-based optical observations. Ono et al. [1993] observed
the emission intensities of PsAs at wavelengths of 427.8 and 844.6 nm using a photometer in
Antarctica, and estimated the energy of the precipitating electrons by combining the ratio of thetwo emission intensities and the model calculation. However, Ono[1993] conducted observations
using the instrument with a narrow field-of-view, and the energy estimation using all-sky
imagers has not yet been performed. In Tromsoe, Norway, several highly-sensitive EMCCD
cameras have been operated, which have simultaneously observed all-sky images of the emission
intensity at the two wavelengths (427.8 and 844.6 nm) with a sampling frequency of 10 Hz. In
this study, we investigate the spatio-temporal variations of precipitating electron energy using
these EMCCD cameras. We estimated the precipitating electron energy of PsA by comparing theemission intensity ratio of the two emission lines using the all-sky image and the emission
intensity calculation results obtained by the Global airglOW (GLOW) model [Solomon, 2017]. In
the presentation, we show the spatio-temporal characteristics of the precipitating electron energyof PsA and discuss energy spectrum of precipitating electrons.

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Energetic electron precipitations associated with pulsating aurora: statistical analysis of low
altitude satellite and VLF subionospheric propagation
F. Tsuchiya, A. Hirai, Y. Miyoshi, K. Shiokawa, H. Ohya, M. Ozaki, Y. Kasahara, A. Kumamoto,
M. Connors, T. Obara, H. Misawa, I. Shinohara

Whistler mode chorus wave is one of candidate plasma waves which causes pitch angle
scattering of relativistic electron trapped in the radiation belt and precipitation of the electrons
into the atmosphere. The energetic electron precipitation (EEP) caused by the chorus wave could
influence significantly on chemistry in the mesosphere and lower thermosphere. Observational
evidence of the EEP associated with pulsating aurora (PsA) which is also caused by the chorus
wave have been reported. However, these results were based on case studies. Here, we used along-term data set of VLF subionospheric propagation in subauroral latitude to investigate
statistical property of the EEP with energy >100keV. We used 25.2 kHz VLF radio signal which
is transmitted at North Dakota (L=3.0) and received at Athabasca University GeoSpace
Observatory (L=4.3) to identify occurrence of EEP in the subauroral latitude. We identified quasiperiodic change in the VLF amplitude whose time scales are similar with PsA and assumed thatpower spectrum density of the amplitude changes integrated from 4 to 20 sec range reflects
occurrence of EEP associated with PsA. We surveyed the EEP from October 2016 to December
2017 and found occurrence distribution of the EEP with respect to magnetic local time (MLT) and
its dependence on AE and Dst indices. The result shows that the EEP occurrence show strong
dependences on MLT and geomagnetic activities. The EEP preferentially occurs in the postmidnight sector during high AE period (the occurrence rate reaches 7% around 2 MLT for
AE>300nT). EEP does not occur when AE<100nT (below 1%). It is worth to note that theoccurrence rate reaches 20% around 1-2MLT for Dst<-40nT while the occurrences are smaller
than 3% for -40nT<Dst<0nT and almost zero % for Dst>0nT. This means that occurrences of the
EEP in subauroral latitude is significant during magnetic storms. We also found 24 EEP events
which had good conjunction with POES /NOAA 19 satellite during the period of the statisticalanalysis. NOAA 19 satellite observed short lived spikes of EEP when the satellite passed overPsA regions or closed to the VLF radio propagation which was detecting the EEP. Among them,
22 and 12 events accountancies >100keV and >300keV EEP, respectively, and 6 events include>800 keV EEP. These results suggest that the chorus wave is responsible for EEP with energy>100keV and the energy of EEP extents up to relativistic energy.

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Efficient particle acceleration in Earths magnetotail and injection of energetic particles into theradiation belts and ring current
D. L. Turner, I. J. Cohen, A. Michael, K. Sorathia, A. Ukhorskiy (APL), J. F. Fennell, J. B. Blake(Aerospace), A. Jaynes (U. Iowa), and G. D. Reeves (LANL)

Earth’s magnetosphere operates as a very effective particle accelerator. Seed populationsof solar wind protons, electrons, and heavier ions initially gain entry along the magnetopause
and via open field lines in the magnetotail, and can then be accelerated up to significantly highenergies (100s keV to > 1 MeV) via a number of acceleration mechanisms active in the central
plasma sheet throughout the magnetotail and the inner magnetosphere. Here, we briefly
summarize details of the latest theory and understanding of those acceleration mechanisms, witha particular focus on relativistic electrons. We show new evidence from a combination of Van
Allen Probes and MMS data supporting the tremendous efficiency of electron acceleration locallywithin Earth’s magnetotail and the significance and implications of such acceleration to theradiation belts in the inner magnetosphere and more generally to solar, planetary magnetosphere,
and other astrophysical systems. We show that: 1) the plasma sheet is at times capable of serving
as a source of relativistic (>500 keV) electrons directly into the radiation belt via substormrelated injections; 2) those relativistic electrons are accelerated locally in the central plasma
sheet, possibly through several different acceleration processes acting in concert; and 3)
injections of MeV electrons directly into the outer radiation belt are possible, though rare despite
there frequently being sufficient sources of those electrons in the plasma sheet. We will alsopresent details and results from test-particle simulations in high-resolution, global MHD fields,
which provide further insight and global context for understanding particle acceleration andsources the energetic particle populations in Earth’s inner magnetosphere.

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High-energy particles - atmosphere interaction
E. Turunen (SGO, University of Oulu)

The Earth is continuously bombarded by energetic charged particles coming from Sun
and outer space. In addition, the geospace environment includes populations of various highenergy particles, a fraction of which is known to precipitate into atmosphere, both driven by solar
wind conditions and intrinsic magnetospheric processes. The multitude of related processes andtheir dynamical variability leads to high variations in spatial, temporal, flux and energy
distributions of the precipitating particles. Interestingly, the precipitation of these high-energy
particles may affect the chemical composition of the atmosphere.
In this lecture we review shortly the processes related to the precipitation of the highenergy particles into the atmosphere, specially the ionization of the atmosphere caused by thehigh-energy particle precipitation and show how related chemical changes appear and my evenaffect the dynamical variability of the atmosphere.
As ability to forecast of the effects by extreme individual space weather events andknowledge of space climate related coupling features in the geospace environment andatmosphere are a must in the future modern society, we need to pay attention to integrated
studies utilizing space-based measurements, modeling and ground-based measurements. We alsoemphasize the integrated studies using satellite measurements, ground-based observations ofvarious types and theoretical modeling efforts.

Page | 86

Van Allen Probes Mission: a Remarkable Journey and Discoveries in Earth’s Radiation Belts
A. Ukhorskiy (JHU/APL)

The morning of 30 August 2012 saw an Atlas 5 rocket launch of the twin Van Allen
Probes, the second spacecraft mission in NASA’s Living with a Star program. The Probes settled
into an elliptic orbit that cut through Earth’s radiation belts, home to highly variable populationsof energetic particles dangerous to astronauts’ health and spacecraft operation. The twin
spacecraft were equipped with instruments designed to determine how these high-energy
particles form, respond to solar variations, and evolve in space environments. Twentieth century
observations of space and astrophysical systems throughout the solar system and out into theobservable universe show the universality of processes that generate intense particle radiation
within magnetized environments such as Earth’s. In this talk we will briefly overview the mission
goals and designs, and discuss a wide rage of fundamental science results and unexpecteddiscoveries made by the Probes over 7 years of the mission that shed light on the particle
energization processes that operate across the universe.

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Simulations of the Relativistic Radiation Belt Electrons Using the VERB-3D CodeD. Wang (GFZ), Y. Shprits (GFZ, UP, UCLA), A. Drozdov (UCLA), I. Zhelavskaya (GFZ), F.
Effenberger (GFZ), A. Castilo (GFZ)

Using the three-dimensional Versatile Electron Radiation Belt (VERB-3D) code, we
perform simulations to investigate the dynamic evolution of relativistic electrons in the Earth’s
outer radiation belt. In our simulations, we use data from the Geostationary Operational
Environmental Satellites (GOES) to set up the outer boundary condition, which is the only data
input for simulations. The magnetopause shadowing effect is included by using last closed drift
shell (LCDS), and it is shown to significantly contribute to the dropouts of relativistic electrons
at high L*. We validate our simulation results against measurements from Van Allen Probes. In
long-term simulations, we test how the latitudinal dependence of chorus waves can affect the
dynamics of the radiation belt electrons. Results show that the variability of chorus waves athigh latitudes is critical for modeling of megaelectron volt (MeV) electrons. We show that,
depending on the latitudinal distribution of chorus waves under different geomagnetic conditions,they cannot only produce a net acceleration but also a net loss of MeV electrons. Decrease inhigh ‐ latitude chorus waves can tip the balance between acceleration and loss toward
acceleration, or alternatively, the increase in high‐latitude waves can result in a net loss of MeV
electrons. Variations in high‐latitude chorus may account for some of the variability of MeV
electrons.
Our simulation results for the NSF GEM Challenge Events show that the position of theplasmapause plays a significant role in the dynamic evolution of relativistic electrons. We also
perform simulations for the COSPAR International Space Weather Action Team (ISWAT)
Challenge for the year 2017. The COSPAR ISWAT is a global hub for collaborations addressing
challenges across the field of space weather. One of the objectives of the G3-04 team “Internal
Charging Effects and the Relevant Space Environment” is model performance assessment andimprovement. One of the expected outputs is a more systematic assessment of model performance
under different conditions. The G3-04 team proposed performing benchmarking challenge runs.
We ‘fly’ a virtual satellite through our simulation results and compare the simulated differential
electron fluxes at 0.9 MeV and 57.27 degrees local pitch-angle with the fluxes measured by the
Van Allen Probes. In general, our simulation results show good agreement with observations. We
calculated several different matrices to validate our simulation results against satellite
observations.

Page | 88

Inter-hemispheric asymmetries in the ground magnetic response and interplanetary shocks
inclination
Zhonghua Xu (Virginia Tech), M.D. Hartinger(SSI), D. M. Oliveira(UMBC), V.A. Pilipenko(SRIR),S. Coyle(Virginia Tech), C.R. Clauer(Virginia Tech)

Interplanetary (IP) shocks drive magnetosphere-ionosphere (MI) current systems thatin turn are associated with ground magnetic perturbations. Previous modelling work has shownthat IP shock impact angle plays a significant role in controlling the subsequent geomagnetic
activity and magnetic perturbations. In this research work, the main question is investigated:
How does the IP shock impact the response time and intensity of the ground magnetic variations
and perturbations in high latitude regions? When the inclined shock strikes one of thehemispheres, will this hemisphere have the most intense ground magnetic response? Will thishemisphere have the first ground magnetic response? In order to answer these questions, we use
data from a chain of Antarctic magnetometers, combined with magnetically conjugate stations
on the west coast of Greenland, to investigate the impacts from these inclined shock conditions
from 2009 to 2017. The statistical results show that interhemispheric asymmetries of the groundmagnetic variations and waves are strongly related to the IP shocks’ impact angles. However, theresults suggest that several factors affect the intensity of ground magnetic response, including
not only the IP shock impact angle, but also local time of the observation, ionospheric conductivity,and other underlying ionospheric conditions.

Page | 89

On the origin of equatorward detachment of auroral arc inferred from conjugate space‐groundobservations and the BATS-R-US – CIMI model
S. Yadav, K. Shiokawa, S. Oyama, Y. Inaba, T. Hori, M. Shoji, C.-W. Jun, S. Imajo, Y. Miyoshi(ISEE, Nagoya University), N. Takahashi, K. Seki, K. Keika, S. Kasahara (The University ofTokyo), T.-F. Chang, S. W. Y. Tam (National Cheng Kung University), B.-J. Wang, Y. Kazama, S.Y Wang (Academia Sinica Institute of Astronomy and Astrophysics), S. Yokota (Osaka
University), Y. Kasaba, F. Tsuchiya, A. Kumamoto(Tohoku University), Y. Kasahara(Kanazawa University), K. Asamura, A. Matsuoka, S. Matsuda, I. Shinohara (Japan Aerospace
Exploration Agency)

One of the key questions in understanding the origin of detached auroral arcs is to
identify the magnetospheric domain and changes therein that lead to the equatorward
detachment of the arc from the main auroral oval. The coordinated ground‐ and space-based
measurement at the time of arc detachment might shed some light on the series of processes
occurring in the magnetosphere that causes the detachment. In this context, we present
observations of an equatorward detachment of auroral arc from the main oval and magneticallyconjugate measurements made by the Arase satellite in the inner magnetosphere. The all-sky
imager at Gakona (magnetic latitude = 63.6°N), Alaska, shows the detachment of auroral arc inboth red- and green-line at local midnight (~01-02 MLT) on 30 March 2017. The electron density
derived from the Arase in-situ observations shows that this arc occurred outside the plasmapause.
Associated with a substorm, the electron flux of energies ~0.1-10 keV locally enhanced at L~4.1
at the arc crossing. We estimated auroral intensities for both red- and green-line by using theArase low-energy electron (0.1-19 keV) flux data. The peak latitude of the estimated intensity
shows reasonably good correspondence with the observed intensity mapped at the ionosphericfootprints of the Arase satellite. Further, we employ the simulation results of the Community
Coordinated Modeling Center (CCMC), the BATS-R-US–CIMI 3D MHD code to understand theconnection between magnetospheric dynamics and the auroral arc detachment. Simulations
successfully show the substorm triggered earthward injection of plasma and the buildup of lower
energy electrons (<20 keV) at the lower radial distance (R) (R ≤ 4) around the time of arc
detachment. These findings indicate that the observed arc detachment at Gakona was associatedwith the substorm induced localized enhancement of 0.1-10 keV electron flux at the inner edgeof the electron plasma sheet.

Page | 90

Evening side EMIC waves and related proton precipitation induced by a substorm
A. G. Yahnin, T. A. Popova, A. G. Demekhov, A. A. Lubchich (PGI), A. Matsuoka, K. Asamura, I.
Shinohara (JAXA), Y. Miyoshi, T. Hori, M. Shoji (ISEE, Nagoya University), S. Yokota (Osaka
University), S. Kasahara, K. Keika (University of Tokyo), , F. Tsuchiya, A. Kumamoto (Tohoku
University), Y. Kasahara (Kanazawa University), H. Kim, S. Noh (NJIT)

We present the results of a multi-point and multi-instrument study of EMIC waves andrelated energetic proton precipitation during a substorm. We analyze the data from Arase (ERG)
and Van Allen Probes (VAP) A and B spacecraft for an event of 16-17 UT on 01 December 2018.
VAP-A detected an almost dispersionless injection of energetic protons related to the substorm
onset in the night sector. Then the proton injection was detected by VAP-B and further by Arase,
as a dispersive enhancement of energetic proton flux. The proton flux enhancement at every
spacecraft coincided with the EMIC wave enhancement or appearance at the same spacecraft.
This data shows the excitation of EMIC waves first inside an expanding substorm wedge andthen by a drifting cloud of injected protons. Low-orbiting NOAA/POES and MetOp satellites
observed precipitation of energetic protons nearly conjugate with the EMIC wave observationsin the magnetosphere. The coefficient of proton pitch-angle diffusion and the strong diffusion
regime index were calculated based on the observed wave, plasma and magnetic field parameters.
The diffusion coefficient maximum corresponded well to the energy range of the observed proton
precipitation. The diffusion coefficient values indicated the strong diffusion regime, in agreementwith the equality of the trapped and precipitating proton flux at the low-Earth orbit. The growthrate calculations based on the plasma and magnetic field data from both VAP and Arase
spacecraft indicated that the detected EMIC waves could be generated in the region of theirobservation or in its close vicinity.

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Excitation mechanisms of the storm-time Pc5 ULF waves by the drift-bounce resonance withring current ions based on the drift-kinetic model
T. Yamakawa(1), K. Seki(1), T. Amano(1), N. Takahashi(1), and Y. Miyoshi(2)(1)Graduate School of Science, University of Tokyo.
(2)Institute for Space-Earth Environmental Research, Nagoya University.

Storm-time Pc5 ULF waves can be excited by ring current ions injected from themagnetotail during substorms. The excitation mechanism of Pc5 waves is a key to understanddynamic variation of radiation belt, since they can drive radial diffusion of radiation belt
electrons [e.g. Elkington et al., 2003]. The drift-bounce resonance [Southwood, 1976] is considered
to be the candidate excitation mechanism. However, the excitation mechanism and global
distribution of storm-time Pc5 waves are far from understood due to the difficulty of non-linear
global simulations. This study aims to investigate the excitation of internally driven ULF waves
based on the global drift-kinetic model.
We performed a kinetic simulation for ring current ions using GEMSIS-RC model [Amano etal., 2011], in which 5D drift-kinetic equation for PSD of ions and Maxwell equations are solved
self-consistently. In order to simulate ion injection from the plasma sheet, we set a localized
high pressure region around midnight consisting of protons. We compare two cases of the initial
velocity distribution; the Maxwellian distribution with the temperature of 16 keV (Case a) andthe butterfly-like velocity distribution with asymmetry in pitch angle direction (Case b). In
Case a, the simulation results show the drift resonance excitation of poloidal and toroidal Pc5
waves in the dayside dusk sector. Global distribution of the excited Pc5 waves indicates thatthey are excited where the local growth rate resultant from the positive PSD gradient in energy
is positive [Yamakawa et al., 2019]. In Case b, excitation of the 2nd harmonic poloidal Pc3 ULF
waves due to the drift-bounce resonance was also identified in addition to Pc5 ULF waves. Ions
contributing to the growth of poloidal mode ULF waves tend to have the pitch angle of about 90
degrees for Pc5 waves and oblique pitch angle for Pc3 waves [Yamakawa et al., 2020]. We will
also report on characteristics of excited ULF waves with a focus of the relative contribution of
the drift and drift-bounce resonances.

Page | 92

Multiple Boris integrators for particle-in-cell simulation
S. Zenitani (Kobe U) and T. N. Kato (NAOJ)

We propose a family of numerical schemes for integrating the motion of charged particles
in particle-in-cell (PIC) simulation. It subcycles the Boris-type 2-step procedure arbitrary n times.
Numerical tests of the new solvers are presented.

Page | 93

Stormer regions in paleomagnetospheres
Bruno S. Zossi, Alvaro R. Gutierrez Falcón, and Ana G. Elias

Determining charged particle’s motion in a magnetic field is an old and challenging
problem due, mainly, to the equations which describe this motion that are generally nonlinear
and an analytical solution is not possible. Stormer, at the beginning of the 20th century, describedglobal aspects of charged particle motion in a dipole field looking at qualitative solutions,whereby space was partitioned into allowed and forbidden regions. Based on the results of twoworks, one by Shebalin in 2004 and the other by Tsareva in 2019, and analyzing Stormer’s twodimensional topological solutions, instead of finding particles trajectories, allowed regions fornon-dipolar magnetic fields are analyzed. We consider these idealized field configurations asplausible plaeomagnetospheres during a polarity transition, which are periods of drastic
consequences for the Earth’s magnetosphere and its shielding capacity.

Page | 94

The 3rd ISEE Symposium

PWING-ERG conference and school on the innermagnetosphere

Main Coveners
Kazuo Shiokawa, Yoshizumi Miyoshi, and Iku Shinohara

Organizing Committee
Tomoaki Hori
Ryuho Kataoka
Satoshi Kurita
Claudia Martinez-Calderon
Yoshizumi Miyoshi
Tsutomu Nagatsuma
Satoko Nakamura
Nozomu Nishitani
Masahito Nose
Yuki Obana
Yuichi Otsuka
Kaori Sakaguchi

Takeshi Sakanoi
Kanako Seki
Atsuki Shinbori
Iku Shinohara
Kazuo Shiokawa
Shin Suzuki
Naoko Takahashi
Yoshimasa Tanaka
Fuminori TsuchiyShin-Ichiro Oyama
Mitsunori Ozaki
Miho Sugiyama (secretary)

Sponsored by