COMMISSION H : Waves in Plasmas (Nov. '2001 - Oct.
'2004)
Edited by Toshimi Okada and Yoshiharu Omura

Based on the papers published from November of 2001 to October of 2004, we have compiled
major achievements in the field of plasma waves and related studies made by Japanese scientists andtheir collaborators. We have categorized the studies into two groups. One is based on observations
and experiments, and the other is theories and computer simulations. Studies in each category arefurther divided into several sections. Each section provides a specific summary of importantscientific achievements rather than a comprehensive report of the whole research activities ofJapanese Commission H. On the other hand, the reference list attached at the end is intended to be
used as a database of all papers we have collected from the Japanese Commission H members.

H1. Space Observation and Experiments of Plasma Waves

H1.1 Hydromagnetic and ULF Wave Phenomena
The three years covered by this report mark the start and growth of the ground-based
remote-sensing of the magnetospheric plasma mass density by using ULF waves; from a
geomagnetic field-line eigen-frequency, that is identified by applying method(s) in a group of
methods called "gradient methods" to the data from two ground magnetometers separated in latitude
by about 1 degree, one can estimate the plasma mass density at the equatorial point along the field
line that runs through the midpoint of the two magnetometer sites. By applying this procedure to achain of ground magnetometers, one can remote-sense the L-dependence of the magnetosphericequatorial plasma mass density.

Kyushu University, Japan, having CPMN (Circum-pan Pacific

Magnetometer Network; previously called 210MM), has been working along this line of research.
Kawano et al. [2002] applied an improved method, called the "amplitude-phase gradient method"(APGM), to actually observed data for the first time, and proved its usefulness; they further
improved APGM so that it can be applied to a chain of ground stations at once.
There exist papers on Pc pulsations: Matsuoka et al. [2002] studied high-latitude narrow-band Pc3
pulsations by using ground magnetometer arrays, SuperDARN radars, and the GEOTAIL satellite.
As a result they found that, at times, there existed high coherence between the pulsations in the dawn
magnetosheath and on the ground, from which fact they suggested that the driving source was
located in the magnetosheath. Tanaka et al. [2004] statistically examined the longitudinal structures

of coherence, amplitude, and phase of the Pc-3 H component by using three longitudinally separated
sub-equatorial stations, and reported for the first time a nearly in-phase structure in the 0730-1700
LT sector and a nearly 180-deg phase jump across 0730 LT.

Motoba et al. [2002; 2003; 2004]

reported the existence of, and studied, Pc5-range magnetic-field oscillations on the ground that wereactually caused by oscillations of a DP2-type current system.
Electric and magnetic field variations inside the plasmasphere associated with suddencommencements (SCs) are analyzed based on the Akebono satellite observations. Shinbori et al.
[2004] showed that intense electric field disturbances with a bi-polar waveform associated with SCs
are followed by a dumping oscillation with a period of Pc3-4 ranges. The dumping oscillation
persisted for about 3-7 minutes in the equatorial region of the plasmasphere. The phase relation of
Ex and Bz components of the oscillation reveals that there is a phase lag of about 90 degrees withcompression nature. From this result, they concluded that the dumping oscillation generated by SC
disturbances may be fast mode waves propagating in the plasmasphere.
The Hall-induced inductive shielding effect (ISE) of the ionosphere affects currents and electricfields that have impinged into the ionosphere from the magnetosphere.

Yoshikawa et al. [2002]

developed

of

a

new

formuladescribing

theinductive

behaviorthemagnetosphere-

ionosphere-atmosphere-Earth system, and by using it, they investigated the ISE on geomagnetic
pulsations. As a result, they found that dayside Pc 3-4 pulsations may be frequently affected by the
ISE.
Many scientists worked on Pi2 pulsations: Yamaguchi et al. [2002] presented a case study inwhich a bursty bulk flow (BBF) in the plasma sheet started prior to the corresponding ground Pi2
onset, but was preceded by the corresponding Pi2 onset at GOES8. From this and another feature
they suggested that the BBF was not the cause of the low-latitude Pi2. Shiokawa et al. [2002]
examined 10s-resolution ground-observed auroral images at the times of Pi2s, but did not find an
oscillation of the auroral luminosity synchronized with the oscillation of Pi2.

Higuchi et al. [2002]

presented a new method to identify the Pi2 onset time; the method is based on statistical science anduses, e.g., Akaike Information Criterion (AIC). Saka et al. [2002; 2004] suggested, mainly based on
observations at the synchronous orbit, that impulsive dusk-to-dawn current near the nightside
synchronous orbit, which current is closed by field-aligned currents, is a source of Pi2.
Nose et al. [2003] investigated a morning-side Pi2 using ground stations and the ETS-VI and
EXOS-D satellites; from the dependence on (L,LT) of the observed waveform, period and phase,they concluded that the Pi2 was caused by the plasmaspheric cavity mode resonance and that its
longitudinal structure was rather uniform.

Uozumi et al. [2004] investigated propagations ofhigh-latitude Pi2s observed by CPMN ground stations.

With the aid of POLAR/UVI auroral

images, they found that Pi2 was observed earlier (by about35s) in the polar cap than in the auroral
region; thus, Pi2 in the polar cap is to be used to determine the substorm onset time.

They also

found the starting MLT of Pi2 to be 22.5 hr.
Fujita et al. [2001] numerically calculated how a Pi2 pulsation propagates in the magnetosphereionosphere system. They also showed its relation with the substorm current wedge [Fujita et al.,2002]. In recent years, a cavity resonance mode has been widely believed as the main mechanism of
low-latitude Pi2 pulsations. Although it has been implicitly assumed that the frequency should be thesame throughout different local time zones for cavity resonance mode, Kosaka et al. [2002] and Han
et al. [2003] found a local time dependence of the dominant frequency.

To explain their results,

Fujita and Itonaga [2003] made a numerical simulation and showed that the frequency can be local
time dependent in the longitudinally non-uniform plasmasphere. The propagation mechanism of Pi2
pulsations has also been investigated using satellite data by and Han et al. [2004]: They confirmedthat the cavity resonance mode is the most plausible mechanism in low latitudes.
As regards Sudden Commencements/Impulses (SC/SI), Takeuchi et al. [2002a] reported thatnegative SIs are not caused by reverse shocks but by varied structures such as tangential
discontinuities at high-low speed stream interfaces, front boundaries of interplanetary magnetic
clouds, and trailing edges of heliospheric plasma sheets.

Takeuchi et al. [2002b] reported that, for

an SC with long rise time (30 min), the corresponding interplanetary shock, observed in the solar
wind, was as sharp as usual SCs, but its normal was highly inclined duskward. Araki et al. [2004]
statistically analyzed SCs, and reported that the rise time is essentially determined by time for aninterplanetary shock to sweep geoeffective magnetopause length L, which they estimated to be about
30 Re.
Nakagawa et al. [2003] reported left-handed ULF waves with frequency of 0.3-1.1 Hz detected by
GEOTAIL at 27 lunar radii upstream of the moon when GEOTAIL was located on field lines that ran
through the lunar wake.

They explained the observation by polarization-reversal of right-handed,sunward-propagating electron whistler waves with frequencies above 1.4 Hz in the solar wind rest
frame, and suggested that the waves were excited by electron beams that had field-aligned-flowed
anti-sunward through the lunar wake.

H1.2 Generation and Propagation of ELF/VLF Waves
The GEOTAIL spacecraft has observed Lobe Trapped Continuum Radiation (LTCR) in the Earth's
distant magnetotail in the frequency range from several hundreds of Hz up to 8 kHz. Takano et al.
[2001, 2004] have estimated the generation region of the LTCR by means of direction finding andthree-dimensional ray tracing analyses. The direction finding analysis with the wave form data of the
LTCR has shown that most of the LTCR propagates along the dawn-dusk direction. Comparing thisresult with the three-dimensional ray tracing analysis, the generation region of the LTCR has been
estimated to be located around the plasma sheet boundary layer and the low latitude boundary layerof the distant magnetotail.

The low latitude boundary layer (LLBL) is a region where solar wind momentum and energy istransferred to the magnetosphere. Enhanced “broadband” electric plasma waves from <5 Hz to 105
Hz and magnetic waves from <5 Hz to the electron cyclotron frequency are characteristic of the
LLBL. Tsurutani et al. [2003] reviewed wave-particle interactions, with focus on cross-diffusion
rates and the contributions of such interactions toward the formation of the boundary layer andpresented a scenario where the global solar wind-magnetosphere interaction is responsible for theauroral zone particle beams, the generation of plasma waves, and the formation of the boundary
layer.
Shinbori et al. [2002] reported that plasma wave phenomena associated with suddencommencements (SCs) are analyzed by using the Akebono satellite observation data which havebeen carried out for more than 13 years since March 1989. The 719 cases of SC events showed anenhancement of plasma waves with one-to-one correspondence to the SC onsets measured at
Kakioka in the inner magnetosphere, plasmasphere, and polar ionosphere. In the middle latitude andin the equatorial region of plasmasphere, electromagnetic whistler, LHR, and ion cyclotron mode
waves are generated, while in the high latitude region, clear enhancements of electrostatic whistler
mode waves with broad-banded spectra are observed.
From time difference between the onset times of SC on the ground and the plasma wave
enhancements, Shinbori et al. [2003b] verified that the propagation nature of the SC disturbances
deduced from these observations has shown two folding signatures; one route is crossing the equator
regions with an average speed of 389.5 km/s, and the other route is passing the polar regions
entering from the cusp region and propagating from the dayside to the nightside polar ionospherewith an average speed of 47 km/s.
Higashi et al. [2004] estimated the impedance of the wire dipole antennas onboard the Akebono
satellite by using the electromagnetic field observations for Omega navigational signals.

Theestimated capacitance and resistance exhibit specific spin variation, which would be caused by theplasma sheath formation around the antenna wires depending on the angle between the antenna
direction and the geomagnetic field line.
Imachi et al. [2004] studied the effective lengths of a wire dipole antenna onboard spacecraft andfound the frequency dependence from DC (static) to AC (wave) electric fields by a “rheometry”
experiment, where a scale model of the antenna is immersed in a water tank with two electrodes
creating a quasi-static electric field in it.
The SS-520-2 rocket experiment was carried out over Ny-alesund, Svalbard, Norway, on Dec. 4,
2000, in the dayside polar region. With the onboard Plasma Wave Analyzer (PWA), Ueda et al.
[2003] have observed impulsive packet-like waveforms with frequencies around 3 to 4 kHz as well
as auroral hiss emissions. The packet-like waveforms were linearly polarized, and appeared for theduration of 100-500 ms, with their spectral peaks well below the lower cutoff of the auroral hiss

emissions. The cross correlation obtained with the PWA interferometry system has estimated thephase velocity of the packet-like waves to be about 60 km/s. With the linear dispersion analysis they
have shown that the most plausible wave mode for the packet-like waveforms is the lower hybrid
wave excited by electron beams. On the other hand, the Electric Field Detector (EFD) onboard theSS-520-2 rocket was designed to observe DC electric fields and plasma waves with frequencies up
to 50 Hz. Miyake et al. [2003] have analyzed EFD data, especially on natural DC electric fields
observed in the noon polar region, by eliminating inductive electric fields with estimating several
parameters. They have shown that natural DC electric fields were observed around the apogee anddescending period of the rocket's trajectory, with their magnitudes of 20 - 40 mV/m, and with almost
south-westward directions.
Two large scientific balloons (PPB: Polar Patrol Balloon) were launched on Jan. 13th, 2003 at
Syowa Station in Antarctica. The balloons reached the altitude of 33 km, and observed importantscientific data for about two weeks. Miyake et al. [2004] have participated in this project for
observation of ELF/VLF electromagnetic waves. They developed a wide-band electromagnetic wave
receiver EMW (ElectroMagnetic Wave receiver) onboard PPB, which can observe waveforms of
ELF waves and power spectra of VLF waves. This EMW receiver worked properly, and succeededin observing clear electromagnetic wave data.
Singh and Hayakawa [2001, 2003] examined the relative merits of ducted and non-ducted
propagations of low-latitude whistlers critically in the light of works done mostly in the Asian
countries. They found a growing consensus in favor of the non-ducted pro-longitudinal mode ofpropagation for nighttime whistlers, and ducted propagation for daytime whistlers. Hayakawa andOhta, [2003] reviewed the direction finding systems and suggested the importance of the use of
direction finding in VLF studies with a few experimental examples.
In an attempt to monitor subsurface VLF electric field changes associated with earthquakes, aborehole antenna has been installed at Agra, India. Some preliminary data analysis by Singh et al.
[2003] has indicated penetration of ionospheric/magnetospheric VLF signals to large depths in thecrustal region and caution for careful identification of seismogenic VLF signals.
Hayakawa and Nickolaenko [2001] reviewed lightning effects onto the mesosphere and lower
ionosphere extensively in relation to the generation of sprites and elves and the associated ELF
transients. Hobara et al., [2001, 2003] and Hayakawa et al, [2004b] have carried out the observationof sprites for the winter lightning in the Hokuriku area of Japan and found that sprites are reallytriggered mainly by +CGs whose charge moment change is exceeding the threshold of 200 ~ 300
C·km.
Otsuyama et al. [2002, 2003a, 2004a, 2004b] studied the VLF signature of ionosphericperturbations (Trimpis) associated with winter lightnings in the Hokuriku area. They found that there
is no significant difference in the Trimpi occurrence rate between – and + CGs. Otsuyama et al.

[2002] also performed an FDTD computer simulation for VLF scattering in the Earth-ionosphere
waveguide. Molchanov et al. [2001] investigated the modulation in the amplitude and/or phase of
subionospheric VLF propagation. The result indicated the significant power in the frequency rangeof atmospheric gravity waves.
Hayakawa et al. [2004a] have presented the long-term observational results on the ionospheric
Alfven resonance at middle latitudes on the basis of observation at Kamchatka and introduced a lotof resonance properties. Nickolaenko et al. [2004c] suggested an alternative mechanism due to thewave interference in the ionosphere and magnetosphere.
Ando et al. [2002] have theoretically investigated the penetrations of power line harmonics andcompared with the previous satellite VLF observation. Soloviev and Hayakawa [2002, 2004] haveproposed an algorithm to study the VLF scattering with taken into account a 3D local ionosphericirregularity over the ground of the solar terminator transition on the basis of a mathematical model,
an asymptotic theory and an appropriate numerical method.
Hayakawa and Otsuyama [2002], Otsuyama et al. [2003b] and Otsuyama and Hayakawa[2004]
have applied the FDTD method to the global Schumann resonances. They demonstrated that thisapplication is expected to be very useful for the complicated ionospheric models (day/night
asymmetry, local ionospheric perturbation etc.). Ando and Hayakawa [2004] have studied theinverse problem extensively for the Schumann resonance data observed at a few stations in the world
and deduced the global distribution of background lightning activity.

Nickolaenko et al., [2004a,

2004b] have developed an algorithm to accelerate the convergence of the time domain formal
solution for the natural ELF transient pulses in the Earth-ionosphere waveguide.

H1.3 Electrostatic Waves Excited by Electrons
Electrostatic waves associated with reconnection phenomena in the dayside magnetosphere region,
were reported by Matsumoto et al. [2003] using the observation results by GEOTAIL skimmed along
the dayside magnetopause. They confirmed the 3-dimensional multiple x-line magnetic
reconnections take place in the same time period. The observed electrostatic waves are Electrostatic
Solitary Waves (ESW) and Amplitude Modulated Electrostatic Waves (AMEW). They showed thatthe enhanced broadband electrostatic emissions associated with reconnection are not random noises
but are nonlinear coherent structures which may provide important dissipation in the electron
diffusion region during reconnection.
In the auroral zone and polar cap region outside the plasmapause, Shinbori et al. [2002, 2003b]
reported that electrostatic whistler mode waves with broad-banded spectra suddenly appear below
the local electron cyclotron frequency associated with SC onsets measured at Kakioka in the plasma
wave data of the Akebono satellite. The ratio (E/H) of electric and magnetic field intensity of theplasma waves at 17.8 kHz obtained by the VLF instruments onboard the Akebono satellite is muchlarger than that of electromagnetic waves in vacuum. This result suggested electrostatic nature of thewhistler mode waves. From simultaneous observation of low energy electrons by the Akebono
satellite, Shinbori et al. [2003b] showed that the electrostatic whistler mode waves are excited byelectron beams with an energy range of less than 100 eV.
Shin et al. [2004] showed the waveforms of the intense electrostatic waves observed in thedownstream

regionarequasi-monochromatic.

They

named

their

waves

Electrostatic

Quasi-Monochromatic (EQM) waves. By comparing the plasma wave data with electron data, theyfound the good correlation of the observations of EQM waves with beam-like cold electrons. Theysuggested that the EQM waves are electron acoustic mode waves based on the preliminary linear
dispersion analyses.

H1.4 Electromagnetic Waves Excited by Electrons
Using the Plasma Wave Instrument (PWI) data from the GEOTAIL satellite, Nagano et al.
[2003a] showed that the angular intensity distribution of the Continuum Radiation (CR) received in
the magnetotail regions changes from isotropic to anisotropic above a specific frequency. Theyinterpret the transition as evidence of the magnetosheath cavity trapping of terrestrial radiation andthat the magnetosheath plasma relaxes at the local Alfven speed, rather than the solar windconvection speed.
Kilometric continuum (KC) radiation was first identified from GEOTAIL plasma wave
observations. This emission has a frequency range that overlaps that of the auroral kilometricradiation (AKR) but is characterized by a fine structure of narrow bandwidth with nearly constant ordrifting frequency. Its source region is probably associated with the low-latitude innermagnetosphere. Menietti et al. [2003] reported new high-resolution electric and magnetic fieldobservations of KC obtained by the Polar plasma wave instrument in the near-source region. Theseobservations show intense electrostatic and less intense electromagnetic emissions near the magnetic
equator at the plasmapause. Simultaneously, GEOTAIL, located at 20 to 30 RE in radial distance,
observes KC in the same frequency range. These data support a possible mode-conversion source
mechanism near a region of high-density gradient.
Green et al. [2004] compared a year's worth of observations of kilometric continuum (KC) fromthe plasma wave instrument (PWI) on GEOTAIL and extreme ultraviolet (EUV) images of theplasmasphere from IMAGE.

KC was observed to be associated with density depletions or notch

structures in the plasmasphere.

IMAGE observations from the radio plasma imager (RPI) during

passage through a plasmaspheric notch structure found that KC was generated in or very near themagnetic equator at steep gradients in density.
GEOTAIL and POLAR Plasma Wave (PWI) and WIND Radio Science (WAVES) experiments’detections from typically widely separated positions of emissions are compared and contrasted byAnderson et al. [2001] in order to study the plasma characteristics near the sources and thegeneration mechanisms for 2fpe emissions, AKR, and other terrestrial wave phenomena.

The

GEOTAIL and POLAR Plasma Wave Instruments (PWI) both included sweep frequency receivers
that had an upper frequency limit of 800 kHz and the WlND WAVES Thermal Noise Receiver(TNR) and Radio Receiver Band I (RAD1) went to 256 kHz and 1024 kHz, respectively. Anderson
et al. [2004] have been able to observe the majority of the AKR spectrum in better detail than withearlier instrumentation and have made many important new discoveries concerning Terrestrial low
frequency (LF) bursts, which are a part of AKR observed during strong substorms. Data from bothsatellite and ground-based experiments show that the LF bursts are well correlated with expansive
phase onsets and occur during very geomagnetically-disturbed periods.
Imhof et al. [2003] compared simultaneous observations of bremsstrahlung X-rays above 2 keVfrom the Polar Ionospheric X-ray Imaging Experiment (PIXIE) on the POLAR satellite with thefrequency distributions of AKR waves measured with the Plasma Wave Instrument (PWI) on the
GEOTAIL satellite. Various AKR characteristics such as the low- and high- frequency cutoffs andthe frequencies at peak intensity are compared with various X-ray parameters such as the magnetic
local times of emission, the total intensities, and the spectral shapes. Imhof et al. [2004] further madecomparisons between X-ray (>2 keV) emissions emanating from the Earth's Northern Hemisphereaurora observed on the Polar satellite and auroral kilometric radiation (AKR) plasma wave
intensities detected on the GEOTAIL satellite. It is found that short time-scale variations of the
LF-AKR activity often correspond to the temporal fine structure of the intensity (5-10 min) of X-ray
auroral emissions. HF-AKR intensity enhancements generally precede enhancements of the X-ray
emissions, while the LF-AKR intensity enhancements generally lag the X-ray enhancements.
The propagation characteristics of auroral kilometric radiation (AKR), the propagation mode,
power flux as well as propagation direction, have been analyzed by applying the wave distributionfunction method to the Poynting flux measurement data of the Akebono satellite. Hosotani et al.
[2001] showed that the power flux of O-mode waves was about 10% of the X-mode wave intensity
in strong AKR emissions. The X-mode AKR waves tend to fill inside the radiation cone of an auroral
field line, while the O-mode AKR waves showed two different propagation directions: one was
directed to almost 90 degree with respect to the local magnetic field and the other showed the
propagation angle of about 40 degree. From the above results, they concluded that the source
locations of the O-mode AKR waves with the above propagation angle located close to the source of
the intense X-mode AKR waves.
It is well known that auroral kilometric radiation (AKR) is intensified during substorms and has agood correlation with AE index. In the case of the magnetic storms, however, AKR characteristics
have not been investigated. Morioka et al. [2003] report unexpected behavior of the storm-time AKR
and its related particle precipitation: (1) AKR often disappears in the initial and main phases of themagnetic storms in spite of the large enhancement of AE index and field-aligned current, (2) At thattime, the energy spectra of precipitating electrons do not show signature of the field- aligned
acceleration but hot electron injection, (3) The radiation activates strongly in the recovery phase, and(4) AKR tends to disappear in larger storms. These results suggest that the field-aligned electric field
which accelerates precipitating electrons and drives field-aligned currents is not formed in the initialand main phases of magnetic storms.
Kumamoto et al. [2001] studied the seasonal variations of AKR activities and up-flowing ion(UFI) events based on long-term plasma wave and particle data obtained by the Akebono satellite.
The analysis results suggested that field-aligned potential drops vary depending on the seasons andcause AKR seasonal variations. Furthermore, Kumamoto et al. [2003a] have investigated seasonaland solar cycle variations of AKR and UFI. In the summer polar region, the peak of the vertical
distribution of the occurrence probability of AKR sources is at an altitude higher than 5000 km witha value of 10% in the solar maximum period and at an altitude of 5000-6000 km with a value of 40%
in the solar minimum period. The AKR and UFI occurrence probabilities decrease with increasing
solar EUV ionization in the ionosphere. Kumamoto et al. [2003b] have derived long-term variationsof ambient plasma density in the auroral regions from whistler wave data, and discussed as a control
factor of solar cycle variations of field-aligned potential drops and AKR sources. AKR occurrence
maximum coincides not with solar wind dynamic pressure peak, but with sunspot number and F10.7
minimum. UFI events and ambient plasma density also show similar behavior.
Shinbori et al. [2003a] showed that the plasma wave data from 263 satellite passages covering the
SC onsets included 85 cases of AKR enhancement within a frequency range from 100 kHz to 1.2
MHz. The start time of the AKR enhancements tended to occur after the SC onsets determined byusing the geomagnetic records of the Kakioka Magnetic Observatory within a time range from 3 to 8
minutes. The averaged time is about 5.26 minutes. Based on the delay time feature, the magnetic
disturbances associated with SCs were thought to propagate from the dayside magnetosphere to thenightside tail region where they compressed the plasma sheet.
The second harmonic wave properties of AKR were investigated by using the plasma wave data of
the Akebono satellite. The statistical analysis results by Hosotani et al. [2003] showed that theprobability of a harmonic event occurrence is more than 60% of all AKR events, whose relationshipbetween the frequencies of the fundamentals and the second harmonics is exactly two times for theupper and lower cut-off frequencies of the spectra as well as the fine structures. They showed thatthe intensity ratio of the second harmonics to the fundamentals exhibits a two-fold nature, with botha linear and a quadratic relationship. Furthermore, the second harmonic waves of the X-mode of
AKR are generated from a source which is identical to that of fundamental waves of the O-mode.
These data analysis results suggest that possible generation mechanism of AKR harmonic structure
should allow the coexistence of different AKR emission processes.

Characteristics of type III solar radio bursts are studied by Kasahara et al. [2001] using
high-frequency resolution of the SFA of the PWI instrument on board the GEOTAIL spacecraft.
Abnormal type III bursts which have separated frequency bands or have prolonged tails at particularfrequencies are often observed. These observations provide observational clues to detect density
inhomogeneities in the upstream interplanetary medium. They propose possible models ofinterplanetary density structures which can account for some type III structures observed.
Murata et al. [2004a] studied the Auroral kilometric radiation(AKR) occultations in the vicinity of
the Earth using two observations by GEOTAIL and POLAR. They compared the dynamic spectra ofboth satellites for eight months paying attention to times and frequencies at which AKR is observed
simultaneously. Then, we carefully examined the AKR illumination regions using the POLAR
two-month orbit data. Two distinct regions where the AKR is occulted are found during the period.
One is the region on the night side of the Earth, where the AKR does not propagate at frequencies >400 kHz. The other region is in the vicinity of the plasmapause, on both the day and night side of the
Earth.
Long-term data analysis results of the seasonal variations of AKR activity by Kumamoto et al.
[2001] suggested that field-aligned potential drops varies depending on the seasons. The idea was
supported by Kumamoto et al. [2001], which clarified the similar seasonal variations of upflowingion (UFI) events. Furthermore, Kumamoto et al. [2003a] have discovered the solar cycle dependenceof vertical distribution of AKR sources and UFI events: AKR and UFI are quiet during solar
maximum while they become active during solar minimum. By Kumamoto et al. [2003b], long-term
variations of ambient plasma density in the auroral regions has been derived from whistler wave data,
and discussed as a control factor of solar cycle variations of field-aligned potential drops and AKR
sources.
By using their model to explain the production of modulation lanes in the dynamic spectra of
Jupiter's decametric emission and the analysis of the curvature of the modulation lanes, Imai et al.
[2001] have obtained the cone half-angle of the emission for the Io-B source. Their results show thatthe value of the cone half-angle remains at a fixed value of 60 degrees for each of the storms
analyzed and that the longitude of the intersection of the active magnetic flux tube with theequatorial plane increased linearly with time. Imai et al. [2002] used the model with newly available
data to test the model and to measure emission source and beam parameters. This measurement is
consistent with the long-held idea that the sources Io-B, Io-A, and non-Io-A are due to the samerotating hollow-cone beam and that the only difference between the latter two is the intensificationof Io-A radiation by the connection with Io in comparison with that of non-Io-A.
The characteristics of the Jovian Anomalous Continuum (JAC) in interplanetary space and in themagnetosheath are investigated using Ulysses observation. Morioka et al. [2004] obtained some newsource characteristics of JAC in addition to those found in previous works. They also evaluatepossible sources of JAC and hypothesize that its origin is Langmuir waves excited at themagnetopause by energetic particles such as QP bursts ejected from the polar magnetosphere. The
relation of magnetospheric disturbances to the generation of JAC is also discussed.
Morioka et al. [2002] investigated the persistence of the most intense Jovian decameter bursts
observed during 17 consecutive years (1974 - 1990). The results showed that even the most intensegroup of decametric storms lasted only one-earth-day or less. When it is assumed that the persistenceof the Jovian decametric radio storms indicate the duration of the Jovian magnetospheric disturbance,
the result implies that even the large Jovian magnetospheric disturbance appears in a major singular
event without sequential activities. From this argument, it would be supposed that the Jovian
magnetosphere unloads the stored magnetospheric energy in a burst and has no geomagnetic
storm-like disturbance.
The dynamic behavior of electrons with energies from a few tens keV to a few MeV and its
relation to plasma waves were examined, using the data from the NOAA and EXOS-D satellites
during the November 3, 1993 magnetic storm [Miyoshi et al., 2003]. After the late main phase,
relativistic electron flux started to recover from the heart of the outer radiation belt, where the cold
plasma density was extremely low and intense whistler mode chorus emissions were detected. The
phase space density showed a peak in the outer belt, and the peak increased gradually. The
simulation of the inward radial diffusion process could not reproduce the observed energy spectrum
and phase space density variation. On the other hand, the simulated energy diffusion due to thegyroresonant electron-whistler mode wave interactions, under the assumption of the Kolmogorov
turbulence spectra, could generate the relativistic electrons without the transport from the outerregion.
Krasovsky et al. [2002] studied the dynamics of high energy electrons in gyroresonance with aquasi-monochromatic circularly polarized whistler mode tracing a geomagnetic field line are studied
numerically.

The space-time dependence of the electromagnetic field manifests itself in theexistence of an approximate invariant of the electron motion.

Under the conditions characteristic of

the magnetosphere, this invariant is found to be conserved with very high accuracy even in theprocess of resonant wave-particle interaction, whereas the constancy of the electron magnetic
moment is strongly violated in the resonance.

H1.5 Observational and Experimental Techniques
Ishisaka et al., [2004] investigated that the relationship between the GEOTAIL spacecraft potential
and the electron number density determined by the plasma wave observations in the solar wind andbroader magnetosphere (except for the high-density plasmasphere) and obtained an empiricalformula shown by the relation between them. Using this empirical formula and plasma particle
measurements, they have shown the distribution of low-energy plasma in the magnetosphere.

Goto et al., [2002] proposed a method to determine the global plasma profile in the plasmaspherefrom the satellite observation data. They adopted a stochastic model to represent the distribution ofplasma. In the model, the parameters were determined by ABIC (Akaike Baysian Information
Criterion) deduced from observed wave data. The validity of our method was evaluated using
simulated data and it was found that the given distributions were successfully reconstructed bysmoothing the observation data appropriately.
A determination method of plasmaspheric electron density profile has been developed by using
OMEGA signals observed by the Akebono satellite. The wave parameters of the signals reflect thedensity along the propagation paths and can be calculated theoretically by ray tracing if the density
profile is given. Thus the profile is reconstructed by model fitting so that the observed andtheoretical wave parameters are consistent with each other. A novel algorithm based on this method
was proposed, in which stochastic factors were taken into account. Goto et al., [2003] proposed atechnique to separate the effects of ionosphere and plasmasphere to the wave parameters in thisalgorithm and apply it to some observational data of Akebono. The result for a recovery phase of ageomagnetic storm reveals the global compression and refilling clearly. In the other example, themethod is applied to examine the symmetry of the plasmaspheric profile. Then Goto et al., [2004]
have improved the method in order to deal with nonducted whistlers which are one of the mosttypical VLF wave in the plasmasphere. The nonducted whistlers originate from atmospherics, andthe occurrence probability at an observational satellite is higher than that of Omega signals.
In order to determine the propagation mode of Jovian decametric radiation (DAM), Nakajo et al.
[2001] instrumented the long range baseline interferometer and examined the stability of the phase
information to the interferometry system. In the long baseline interferometer observation, it has been
well known that the observed fringe phases are fluctuated by the temporary variation of TEC (Total
Electron Contents). The dual frequency interferometer method is a powerful method to eliminate theinfluence of TEC; however, the problem caused by the dependence of the linear equations must be
considered in the case of the observation of Jovian decametric radiation.
S-burst phenomena of DAM are investigated by Oya et al. [2001a], who reported that dynamic
spectra of the S-bursts are obtained by using a high time resolution radio spectrograph with a time
resolution of 2 ms and a bandwidth of 2 MHz. Within the occurrence feature of 65 S-burst events
observed in the period from 1983 to 1999, 26 events have been identified as the S-N burst events,
which are characterized by the interaction between the S-burst emissions and the Narrow band
emissions.
Oya et al. [2001b] have developed array antenna system and multi-frequency interferometer
network to investigate the electromagnetic radiation process in the Jovian magnetosphere. To
understand the energy source and the radiation process of DAM with correlation to the Jovian
auroras, ionosphere-magnetosphere couplings and interactions with satellite Io, it is important toobtain the information on the source location and the polarization of DAMs. The array antenna
system consists of 9 antennas covering a frequency range from 20 MHz to 30 MHz. The new long
baseline interferometer system employs the multi-frequency interferometer method by which
ionosphere scintillation effect can be largely reduced.
In the dynamic spectra of the S-N burst, Oya et al. [2002] found the trend of emissions withnegative and slower frequency drift named as "Trailing Edge Emission (TEE)", which are often
observed shortly after the appearance of the S-burst. Detailed analyses of these phenomena revealed
that the TEE is not a manifestation of S-burst with slower drift rate but a variation of N-burst. The
results suggested that S-burst and the associated TEE are formed simultaneously started from acommon region with different drift rates.
Oya and Iizima [2003] proposed a new method for detecting the phase difference of cesium
frequency standards facilitated at coupling stations of an interferometer of 100km range baselines forobservations of decameter wavelength radio waves. The feasibility of the proposed method has beenverified by applying the method to observations of a 100km range baseline interferometer for
decameter wavelength radio waves at Tohoku University selecting the radio-wave sources in the
Cassiopeia A supernova remnant as the objective.
Hashimoto et al., [2003] developed a software wave receiver utilizing a programmable down
converter (HSP50214B) and a digital data processor (TMS320C31) to obtain the spectra andwaveform of plasma waves in wide frequency ranges of ELF, VLF and LF bands with highfrequency and time resolution. They reported the successful flight test by using the SS520-2 rocket
experiment on Dec. 2000 launched from Ny-Alesund in Svalbard in Norway, which indicates thatthe new plasma wave receiver to be used for future planet explorers and space observation missions.
Tsutsui [2002] developed a newly developed system for measuring electromagnetic (EM)environment in the earth to detect the earth-origin electric pulses which were leaking out of theground. The author reported that intensity of the electric pulses detected above the ground was
weaker than those in the earth.

H2. Theory and Computer Experiments on Plasma Waves

H2.1 Wave Instabilities
Computer simulations of the self-consistent nonlinear evolution of electrostatic andelectromagnetic 2fp waves excited by electron beams with electromagnetic particle code have been
carried out by Kasaba et al. [2001]. Their results showed that in both one- and two-dimensional
periodic systems an electrostatic 2fp wave is generated at twice the wave number of forward
propagating Langmuir waves by wave-wave, while the electromagnetic 2fp wave is only excited in
two-dimensional systems.

Kasaba et al. [2004] studied several topics related to the 2fp radiation generated in the terrestrial
electron foreshock. They present a summary of the generation mechanism of electrostatic andelectromagnetic 2fp waves and the electron acceleration at the quasi-perpendicular shock.
Omura et al. [2003] have studied the response of thermal plasmas to an induction electric field via
one-dimensional particle simulations. Because of acceleration of electrons and ions in the opposite
directions, there arise counter streaming electrons and ions that cause the Buneman instability. hey
found that the induction electric field can form an electron beam along the magnetic field line.
Matsukiyo et al. [2004] succeeded in reproducing the high-frequency electric wave spectra
observed in the auroral upward current region by one-dimensional particle-in-cell simulations. Using
distribution functions suggested by the measurements, they found that in the nonlinear state, ion
acoustic waves and electron two-stream (Langmuir) waves dominate the spectrum. In the absence ofcold electrons, electron acoustic waves are not excited initially but appear only at a late time. This isdue to the result of the formation of a two-temperature electron plasma by nonlinear interactions
when all other instabilities have saturated.
Deng et al. [2004] have provided possible evidence of multiple X lines collisionless reconnectionin the magnetotail at the microscopic level by combining the observations of plasma, magnetic field,
particles, and waves. On 11 December 1994 the GEOTAIL spacecraft encountered an active
reconnection diffusion region around the X line in the Earth's magnetotail. Three interesting features
were observed. One is quadrupole pattern of the out-of-plane By magnetic field component during
the passage of magnetic islands and the crossing of the neutral sheet. The second is a direction
reversal of the electron beams in the vicinity of the separatrix of the magnetic topology ofreconnection. The third is a clear plasma flow reversal.
Whistler-mode wave-electron interactions constitute an important physical mechanism in the
Earth’s magnetosphere and the radiation belts of the magnetized planets.

Omura and Summers[2004] performed an electromagnetic particle simulation to confirm analytical results for the growthrate of whistler-mode waves in a relativistic bi-Maxwellian plasma with given temperature
anisotropy.

H2.2 Wave Propagations
Okada et al. [2001] evaluated the propagation characteristics of ELF and VLF electromagnetic
waves in the Martian ionosphere, and discussed the possibility for the detection of Martian
atmospherics by NBOZOMI observation.
To investigate the occultation of auroral kilometric radiation (AKR) in the vicinity of the Earth,the dynamic spectra from GEOTAIL and POLAR satellites are compared by Murata et al. [2004a].
They reported two distinct regions of AKR occultation, where are the night side of the Earth andvicinity of the plasmapause.

In collision-free magnetized plasma the solution of the wave equation becomes singular andunstable. To cope with this problem, Takano et al. [2003] developed an integral approximation
method. By applying this technique to the mode coupling from a Z mode to an L-O mode in spaceplasma, they evaluated the mechanism of wave energy absorption at the resonance point.
In order to investigate detailed space and time evolution of elves, Nagano et al. [2003b] computed
rigorously propagation in a magnetized ionosphere of EM pulses radiated by lightning current
strokes, by using a full-wave analysis. Computed results showed that an optical ring is created at thealtitudes of 85-100 km above the lightning, quickly expanding horizontally over 200 km within < 1
ms, which is consistent with the actual observation of elves.
Ozaki et al. [2004] computed rigorous wave intensities on the ground surface and in theionosphere caused by earthquakes, by using the full-wave analysis. The computed results in thefrequency range from 10 Hz to 10 kHz showed the difference in spatial distributions of the wave
intensities due to the whistler-mode propagation in the ionosphere.
Hikishima et al. [2004] investigated the cyclotron resonance and pitch-angle diffusion of theresonant electrons, to analyze the generation mechanism of the chorus emissions. Their results
indicated that the initially large pitch-angle anisotropy of the resonant electrons is rapidly
pitch-angle diffused by a generated whistler mode wave, and the pitch-angle anisotropy decreases
down to the small anisotropy which saturates wave growth.
Ikeda [2002] examined the possibility of the sideband wave generation in whistler-mode via a
non-linear Doppler-shifted cyclotron resonant interaction between untrapped electrons and thewhistler mode carrier signal by using a new equation system. The untrapped electrons resonant with
the quasi-monochromatic whistler mode signal are phase-bunched with the trajectory gap, justoutside the separatrix, on the phase space in the frame of electron of the Doppler-shifted cyclotron
resonance with the carrier. Then, they may be able to radiate the whistler mode sideband waves withfrequencies of fundamental, second and third harmonics, whose currents may never be zero becauseof strong non-linear interaction. It is imagined that, at the same time, two kinds of plasma may
interact with the carrier signal to form the broadening, and with the sideband waves showing
frequencies of fundamental, second and third harmonics. The fundamental, second and third
harmonics sideband wave frequencies may be related to the saturated amplitude of the carrier signal.

H2.3 Shocks and Particle Acceleration
Nishimura et al. [2002] studied the acceleration and heating of electrons at quasi-parallel shockwaves by means of a one-dimensional full particle computer simulation. Their simulation shows thatthe ion beam instability due to the anomalous cyclotron resonance excites whistler mode waves in
the upstream region.

The electron acceleration parallel to the magnetic field results from theparallel electric fields caused by both the whistler mode waves and the electrostatic shock potential.

They found that the contribution of the whistler waves to the parallel acceleration is as important asthat of the electrostatic shock potential below the critical Mach number.
The properties of reformation in perpendicular collisionless shocks were investigated by
Nishimura et al. [2003] using one-dimensional particle-in-cell simulation. The reformation is known
to be associated with ion reflection at the shock ramp and subsequent ion gyromotion in the
upstream region.

However, it is also known that the shock reforms intermittently at sufficiently

high Mach number if ions are reflected continuously at the ramp.

The simulations were performed

to investigate this issue and they found that the shock potential changes dramatically through there-formation cycle, so that the potential variation leads to the intermittent response of the shock.
Hada et al. [2003] analyzed the shock front nonstationarity of perpendicular shocks insuper-critical regime by examining the coupling between "incoming'' and "reflected'' ion populations.
For a given set of parameters including the upstream Mach number and the fraction alpha ofreflected to incoming ions, a self-consistent, time-stationary solution of the coupling between ion
streams and the electromagnetic field was sought. The analytic results were in good agreementwith full particle simulations for low beta case.
Futaana et al. [2003] studied the nonthermal ions which were measured by Particle Spectrum
Analyzer/Ion Spectrum Analyzer (PSA/ISA) on board the Nozomi when the spacecraft was very
close to the Moon. It was found that the nonthermal ions were protons and had a partial ring
structure in the phase space.

By conducting particle tracing calculation, their source location was

found to be the dayside of the Moon, and the nonthermal ions seem to have large velocities when
they were generated. It was proposed that the electromagnetic field in the vicinity of the Moon musthave a dynamic structure, possibly a miniature bow shock associated with a local magnetic anomaly,
where some of the solar wind protons are deflected to forms a partial ring structure in the velocity
phase space.
Cross field diffusion of energetic particles (cosmic rays) in a two-dimensional static magnetic
field turbulence is studied by Otsuka and Hada [2003] by performing test particle simulations.
Qualitatively different diffusion processes were observed depending on the ratio of Larmor radius tothe correlation length of the magnetic field fluctuations. The diffusion was found to be composed ofseveral regimes with distinct statistical properties, which can be characterized using Levy statistics.
Lembege et al. [2004] published a review to address a subset of unresolved problems incollisionless shock physics from a theoretical and/or numerical modeling point of view. The topics
are the nonstationarity of the shock front, the heating and dynamics of electrons through the shock
layer, particle diffusion in turbulent electric and magnetic fields, particle acceleration, and theinteraction of pickup ions with collisionless shocks.
Supra-thermal particle acceleration for a perpendicular magnetosonic shock was discussed by
Hoshino [2001] by focusing on the interaction of particles with a large amplitude solitary wave

formed in the shock front region/shock transition layer. The author showed that the shock surfing
acceleration in a relativistic electron-positron shock occurs under the interaction of the trapped
particles by the magnetosonic solitary wave with the shock motional electric field, and that thetrapped particle can be efficiently accelerated up to the shock potential energy determined by aglobal shock size.
Hoshino and Shimada [2002] studied the suprathermal electron acceleration mechanism in aperpendicular magnetosonic shock wave in a high Mach number regime by using a particle-in-cellsimulation, and found that shock surfing/surfatron acceleration producing suprathermal electrons
occurs in the shock transition region, where a series of large-amplitude electrostatic solitary waves( ESWs) are excited by Buneman instability under the interaction between the reflected ions and theincoming electrons.
Hoshino and Mukai [2002] found that the energy spectrum of electrons in magnetic reconnection
has a suprathermal population above a few keV, and more importantly the higher energy spectrum
can be fitted by exp(-αv). A simple model to explain the suprathermal electrons based on a Fermi
acceleration process was proposed.
Shimada and Hoshino [2003] investigated the electron-ion coupling process under Buneman
instability between inflow electrons and reflected ions in the shock transition region. The study
examined how electron holes affect the ions and interact with them. This study may provide a firstindication of what regulates strong electron heating in the shock transition region through thecoupling process between the electrons and ions.

Shimada and Hoshino [2004] evaluated the effectof the frequency ratio omega(pe)/Omega(ce) on the electron energization in the shock transition
region by using periodic simulations with realistic mass ratio. Their results showed that whenomega(pe)/Omega(ce) is less than or equal to 1 no electron phase space hole is generated and whenomega(pe)/Omega(ce) is greater than or equal to 10 a clear series of electron phase space holes isgenerated.
Trakhtengerts et al. [2002] developed the kinetic theory for runaway electrons in a stochastic
electric field. The general kinetic equation for the isotropic part of the electron distribution function
was derived and was simplified to the differential form for a particular case of electric field spectral
intensity. The stationary analytical solution and numerical dynamic solutions were obtained and werediscussed in connection with the problem of energetic electrons in a thunderstorm cloud.
Electron acceleration by a stochastic (in space) electric field in the atmosphere was considered by
Trakhtengerts et al. [2003a] taking into account limited scales of the acceleration layer. Stationary
solutions of the kinetic equation in a finite layer were analyzed numerically in the presence of sourceof energetic electrons. These solutions were discussed in connection with γ- and x-ray emissions
observed inside thunderclouds.
A role of the second-order cyclotron resonance effect in the self-consistent approach to theproblem of triggered ELF/VLF emissions was estimated by Trakhtengerts et al. [2001].The main andgeneral conclusions are: (1) The second-order cyclotron resonance effects give an important
contribution to triggered ELF/VLF emissions. (2) The short pump whistler wave packets generate
fallers, while the long packets generate predominantly rising tones. (3) There are critical maximaland minimal values for the pump wave pulse duration.
Trakhtengerts et al. [2003b] considered the effect of initial phase bunching of energetic electrons
on the generation of triggered ELF/VLF emissions in the magnetosphere. They focused on aphase-bunched beam in the velocity space, which serves as a traveling-wave antenna emitting
secondary waves, and showed that the antenna field is significant as the seed wave which is further
amplified by the same beam via the cyclotron resonant mechanism.
Electron accelerations in the outer radiation belt was investigated based on the Akebono
observations by Obara et al. [2001]. Increase of the electron flux occurred in low L region and in low
energy. Phase space density for MeV electrons had a peak around the center of the outer radiation
belt. This means the internal acceleration took place in the outer radiation belt during the storm
recovery phase.
Obara and Li [2003] showed that MeV electrons moved Earthward quickly with a suddencommencement, filling the so-called the slot region, and that the electron flux decayed slowly,
forming the slot structure again. Time constant of the decay was studied.
Miyoshi et al. [2003] examined the dynamic behavior of electrons with energies from a few tens
keV to a few MeV and its relation to plasma waves, using the data from the NOAA and EXOS-D
satellites during the November 3, 1993 magnetic storm, and then numerically investigated theelectron acceleration process at the storm. Their study suggested that the acceleration by whistler
mode chorus via gyroresonant wave-particle interactions outside the plasmapause could play animportant role to generate the storm-time relativistic electrons.
Katoh et al. [2003] studied particle acceleration processes due to wave particle interactions by
employing numerical simulations based on a hybrid algorithm in order to investigate the merging
process of cometary oxygen ions into the solar wind and verify a elementary process of energizing
mechanism of relativistic electrons in the outer radiation belt during a geomagnetic storm recovery
phase.

H2.4 Nonlinear Effects
Krasovsky et al. [2003] studied the electrostatic pulses recorded by the GEOTAIL spacecraft andlabeled electrostatic solitary waves (ESW) within the framework of Bernstein-Greene-Kruskal(BGK) solitons. The general approach developed in the article applies to arbitrary particle
distributions of the background plasma, velocities of the BGK solitons and wide variety of therecorded ESW waveforms. The new models and physical interrelations reveal universal features ofthe BGK soliton structure and allow a direct juxtaposition with the observations. The establishedinterconnections between the physical characteristics of the waves agree well with the GEOTAIL
data on ESW waveforms.

Krasovsky et al. [2004] clarified the qualitative differences between theactual three-dimensional (3-D) perturbations and the well-known 1-D Bernstein-Greene-Kruskal(BGK) modes of the electron hole type. They showed that the anisotropy caused by the geomagnetic
field is a decisive factor and the hole-like structures is closely connected with thequasi-one-dimensional nature of the electron motion, predominantly along the external magnetic
field.
The formation process of ESW was studied by Umeda et al. [2002]. They conducted one- andtwo-dimensional electrostatic particle simulations with open boundaries. In the open system, spatial
structures of electron holes vary depending on the distance from the source of the electron beam. A
lower hybrid mode is excited locally in the region close to the source of the electron beam throughcoupling with electron holes at the same parallel phase velocity. The lower hybrid mode modulates
electron holes excited in later phases, resulting in formation of modulated one-dimensional
potentials.
Umeda et al. [2004] extended the previous electrostatic particle model to an electromagnetic
particle model. In the present two-dimensional simulations of an electron beam instability,
electromagnetic field components are enhanced around two-dimensional electron holes. They foundthat the enhancement of electromagnetic fields is due to a current formed by electrons undergoing
the E × B 0 drift, where the electric field is a perpendicular electrostatic field at the edge of a
two-dimensional electron hole. An electromagnetic beam mode is excited by the current due to thedrifting electrons moving with the electron hole.
Generation of electrostatic multiple harmonic Langmuir modes during beam-plasma interaction
process has been observed in laboratory and spaceborne active experiments, as well as in computer
simulation experiments. Despite earlier efforts, such a phenomenon has not been completely
characterized both theoretically and in terms of numerical simulations. Yoon et al. [2003] foundanalytic expressions for harmonic Langmuir mode dispersion relations and compared their resultswith numerical simulation results.
theory in which

Gaelzer et al. [2003] developed generalized weak turbulence

multiharmonic Langmuir modes were included and the self-consistent particle andwave kinetic equations were solved. The result shows that harmonic Langmuir mode spectra exhibit
a quasi-power-law feature, implying multiscale structure in both frequency and wave number spacespanning several orders of magnitude. The generation of harmonic Langmuir modes during beam
plasma interaction was studied by Umeda et al. [2003] with nonlinear theoretical calculations andcomputer simulations. In their Vlasov simulation code, multiple harmonic Langmuir modes up to
12th harmonics can be included in contrast to previously available simulations which were restricted
to the second harmonic only. The frequency-wave-number spectrum obtained by taking the Fourier

transformation of simulated electric field both in time and space showed an excellent agreement withthe theoretical nonlinear dispersion relations for harmonic Langmuir waves. The saturated wave
amplitude features a quasi-power-law spectrum which reveals that the harmonic generation process
is an integral part of the Langmuir turbulence.
A linear analysis and 2-1/2dimensional electromagnetic full-particle simulations were performed
by Fujimoto and Machida [2003] to investigate mechanisms of an electron heating due to an intenseHall current, which is caused by a large velocity difference between electrons and ions in theoutflow region inside the diffusion region of the magnetic reconnection.
Shklyar and Matsumoto [2002] studied the initial problem of plasma wave dynamics in thepresence of a sharp density jump that divides the space into transparent and opaque regions. A wave
packet was assumed to be initially localized in the transparent region. The transient process of field
penetration beyond the density barrier during the wave packet reflection from the density jump wasinvestigated.
In order to self-consistently study the kinetic processes at the Venus ionopause, Terada et al.
[2002] calculated the Venus ionopause-solar wind interaction region kinetically, including theionosphere, ionopause transition layer, magnetosheath, and solar wind, by applying boundary-fitted
coordinates to the particle-in-cell code. They found that the distribution of ionopause surface waves
generated by the Kelvin-Helmholtz (K-H) instability exhibits a clear asymmetry between
hemispheres of upward and downward solar wind motional electric fields. Accordingly, theasymmetrical momentum transport across the ionopause yields an asymmetrical convection patternof the ionosphere. Terada et al. [2004] extended their work to study a viscous process associatedwith the K-H instability around the ionopause, which is less well understood compared to the pickup
process of exsospheric ions and electrons. They studied the relative importance of the escapeprocesses for the case of low solar wind dynamic pressure as well as for the high dynamic pressurecase, and showed the viscous removal process occurring at the ionopause plays a significant role in
the ion escape from Venus.
A merging process of cometary oxygen ions into the solar wind particle was studied by Katoh et al.
[2003] employing numerical simulations based on a hybrid algorithm.

The results of

one-dimensional hybrid simulation shows that a spatial extent of interaction region surrounding
comet nucleus is deeply related to the ion beam instability driven by a field aligned motion ofpicked-up ions.

Katoh and Omura [2004] studied resonant interaction between relativistic electrons

and whistler mode waves excited by a temperature anisotropy using the hybrid simulation. The
simulation shows that selected resonant electrons are effectively accelerated in a homogeneous
system where both forward and backward traveling waves interact with the relativistic electrons.
Matsukiyo and Hada [2002] studied a long time evolution of cyclotron maser instability at nullwave number (k=0) which is destabilized by relativistic ring distribution of plasma through thecyclotron resonance.

They performed particle simulations using a plasma which consists ofgyrotropic or nongyrotropic relativistic ring electrons, background positrons, and backgroundelectrons. The linear theory predicts that, when the initial ring energy is strongly relativistic, there
appears a critical initial ring momentum at which the system is marginally stable. Numericalsimulations show, however, that the system is nonlinearly unstable even when the initial ring
momentum exceeds the critical momentum.
Matsukiyo and Hada [2003] examined the dispersion relation and nonlinear evolution of theparametric instabilities of circularly polarized Alfven waves in a relativistic electron-positron plasma.
First, the nonlinear dispersion was solved in a nonrelativistic limit, then the weakly relativistic effectwas examined. The one-dimensional full particle simulation and bicoherence analysis of thesimulation result suggest that successive decay via the interaction between the parallel propagating
Langmuir-like wave and antiparallel propagating Alfven-like wave can efficiently generate acontinuum of low frequency electromagnetic waves, which can interact with energetic particles.

H2.5 Active Experiment and Spacecraft-Environment Interaction
Using topside sounder data obtained by the Ohzora (EXOS-C) satellite, Uemoto et al. [2004]
investigated the structure and dynamics of the ionization ledge in the equatorial topside ionosphere.
They found that the ionization ledge observed in the local noon time period shows similar nature as
it has been theoretically predicted for the F3 layer. Also they indicated that the seasonal dependenceof the occurrence probability of the ionization ledge has a tendency contrary to that of the F3 layer.
Usui et al. [2004a, 2004b] for the first time applied electromagnetic PIC (Particle-In-Cell)computer simulations to analyze the antenna characteristics in magnetized plasma. They particularly
examined the electron kinetic effects on the antenna impedance. It is confirmed that the mostobvious resonance point is the local Upper Hybrid Resonance frequency. As the electron temperature
increases, the resonance frequency also increases in accordance with the modification of dispersion
relation for the UHR branch.
Numerical simulations on active perturbation of space environment by microwave powertransmission (MPT) and plasma beam emission for the spacecraft charging control have been
performed. Usui et al. [2002] studied a three-wave coupling process occurring in an active
experiment of MPT in the ionospheric plasma by performing one dimensional electromagnetic PIC(Particle-In-Cell) simulations. Continuous emission of intense electromagnetic waves from anantenna located at a simulation boundary excites a low-frequency electrostatic wave as the result of anonlinear three-wave coupling.

Usui et al. [2004c] also studied the basic process of the spacecraft

charging and its neutralization using dense plasma emission by performing PIC simulations.

They

particularly examined the electron/ion flux to the charged body and the corresponding potential
variation. It is shown that the negatively charged body is neutralized mainly by the enhancement of

ion flux of the emitted plasma In the transient process of the charge neutralization, they found very
turbulent current variation at the emitted plasma cloud region, which may cause electromagnetic
perturbation in the vicinity of the body.

H2.6 Techniques of Data Analysis and Computer Experiments
One of the most important methods for the studies of plasma waves observed by spacecraft is tocompare them with other observations either with same spacecraft or with other spacecraft.
Simultaneous ground-based observations also help our understandings of the plasma wave
generation mechanisms. Murata [2003] and Murata et al. [2002a] have constructed a softwaresystem (STARS) to gather observation data files individually managed at several organizations. It
also provides a variety of functions to plot and analyze the data. For 3-dimensional data analyses ofthe observation data, a virtual Earth’s magnetosphere system (VEMS) is produced by Murata et al.
[2004b]. Murata et al. [2002b], Murata et al. [2002c], Murata [2002d] and Murata et al. [2002e] havedeveloped systems to achieve high-performance computing and to support computer simulations forplasma particle simulations.
Akimoto et al. [2003] developed a new general-purpose computational technique for classifying
the plasma waves in a systematic way from database of scientific satellite. Firstly, they propose a
two-step cluster analysis for the classification. Applying this cluster analysis to the key parameters of
the Akebono wave data, they could make some representative classes of wave phenomena with asmall amount of calculation time. In order to determine the suitable number of representative class,they propose an evaluation function with AIC.

Finally, they discriminated to the representativeclasses and exception.
Kasahara et al. [2002] introduced new computational techniques for extracting the attributes
and/or characteristics of the plasma waves and particles from the enormous scientific database.
These techniques enable us to represent the characteristics of complicated phenomena using a few
key-parameters, and also to analyze large amount of datasets in a systematic way. These techniques
are applied to the observational data of the ion heating/acceleration phenomena in the auroral region
obtained by the Akebono satellite.
Tanaka et al. [2004] developed a general-purpose system which manages and provides various
kinds of information accumulated in their university. One of the most important points in the designof the system is management of the enormous amount of data, which comes up to several tera-bytes
in the field of natural science in some cases. They constructed a database system on the geospace
radio environment obtained by the Akebono satellite.
The lunar radar sounder (LRS) experiment onboard SELENE (SELenological and ENgineering
Explorer) has been planned for observation of the lunar surface and subsurface structures. The
computer simulation of the LRS observations and development of data analysis method have been

performed by Kobayashi et al. [2002a] using newly developed simulation code, Kirchhoff
approximation sounder simulation (KiSS) code. It has been shown by the simulation that thesubsurface echoes are detectable by using data stacking technique. Kobayashi et al. [2002b] has also
performed the simulation of the LRS observations in the lunar highland regions, where subsurface
echoes are severely masked by confusing surface echoes. The application of the synthetic apertureradar (SAR) method for subsurface echo analysis in the lunar highland region has been proposed
based on the simulation results.
As for the effective method for EMC of spacecrafts in space plasma, Okada et al. [2004]
demonstrated the sheilding effects of the conductive hood covering the solar sensor onboard
NOZOMI spacecraft by performing a series of FDTD simulations with different configurations of aconductive hood.

References

Akimoto, Y., Y. Goto, Y. Kasahara, T. Sato [2003], “Automatic classification of electromagnetic
waves from database obtained by the Akebono satellite (in Japanese)”, Transcations of IEICE,
J86-D2(5), pp.598-607.

Anderson, R. R., H. Matsumoto, K. Hashimoto, H. Kojima, I. Nagano, Y. Kasaba, M. L. Kaiser, J.-L.
Bougeret, and J.-L. Steinberg [2001], “Using Geotail, Wind, and Polar observations of solar,interplanetary, and terrestrial plasma wave and radio emissions to identify source characteristics”
Planetary Radio Emissions V, edited by H.O. Rucker, M.L. Kaiser and Y. Leblanc, Austrian
Academy of Science Press, Vienna, Austria, pp.297-310.

Anderson, R. R., H. Matsumoto, K. Hashimoto, H. Kojima, Y. Kasaba, M. L. Kaiser, J-L. Bougeret,
J-L. Steinberg, and G. Rostoker [2004], "Geotail, Polar, and wind observations of auroral kilometricradiation", Frontiers of Magnetospheric Plasma Physics, COSPAR Colloquia Series, vol.16,
pp.205-219.

Ando, Y., M. Hayakawa, and O. A. Molchanov [2002], “Theoretical analysis on the penetration of
power line harmonic radiation into the ionosphere”, Radio Sci., vol.37, No.6, 1093, doi:
10.1029/2001RS002486.

Ando, A. and M. Hayakawa [2004], “2-D finite difference analyses of Schumann resonance andidentification of lightning distribution”, IEEJ Trans. Fundamentals and Materials, vol.124, No.12, pp.

1225-1231.

Araki, T., T. Takeuchi and Y. Araki [2004], "Rise time of geomagnetic sudden commencements Statistical analysis of ground geomagnetic data", EARTH PLANETS AND SPACE 56 (2): 289-293
2004.

Deng, X. H., H. Matsumoto, H. Kojima, T. Murata, R. R. Anderson, W. Baumjohann, and R.
Nakamura [2004], “Geotail encounter with reconnection diffusion region in the Earth's magnetotail:Evidence of multiple X lines collisionless reconnection?”, J. Geophys. Res., vol.109,
pp.A05206-1-A05206-9.

Fujimoto, K., and S. Machida [2003],

An electron heating mechanism in the outflow region fromthe X-type neutral line , J. Geophys. Res., vol. 108, No. A9, 1349, 10.1029/2002JA009810.

Fujita, F., T. Mizuta, M. Itonaga, A. Yoshikawa, H. Nakata [2001],

Propagation property oftransient MHD impulses in the magnetosphere?ionosphere system: The 2D model of the Pi2
pulsation , Geophys. Res. Lett., Vol28(11), pp.2161-2164.

Fujita, S., H. Nakata, M. Itonaga, A. Yoshikawa, T. Mizuta [2002], “A numerical simulation of thePi2 pulsations associated with the substorm current wedge”, J. Geophys.Res., vol.107, No.A3,
1034,doi:10.1029/2001JA900137.

Fujita, S., and M. Itonaga [2003], “A plasmaspheric cavity resonance in a longitudinally
non-uniform plasmasphere”, Earth Planets Space, 55, 219-222, 2003. Res. Lett., vol.30, 1326,
doi:10.1029/2002GL016319.

Futaana. Y., S. Machida, Y. Saito, A. Matsuoka, and H. Hayakawa [2003], “Moon-related nonthermal
ions observed by Nozomi: Species, sources, and generation mechanisms”, J. Geophys. Res., vol.108,
No. A1, 10.1029/2002JA009366.

Gaelzer, R., P. H. Yoon, T. Umeda, Y. Omura, and H. Matsumoto [2003], "Harmonic Langmuir
waves: II. Turbulence spectrum", Physics of Plasmas, vol.10, pp.373-381.

Green, J. L., S. Boardsen, S. F. Fung, H. Matsumoto, K. Hashimoto, R. R. Anderson, B. R. Sandel,
and B. W. Reinisch [2004], "Association of kilometric continuum radiation with plasmasphericstructures", J. Geophys. Res., vol.109, pp.A03203-1-A03203-7.

Goto Y., Y. Kasahara, and T. Sato [2002], A Flexible Modeling of Global Plasma Profile Deduced
from Wave Data Progress in Discovery Science, LNCS, Springer, 2281, pp.438-448.

Goto Y., Y. Kasahara, and T. Sato [2003], Determination of Plasmaspheric Electron Density Profile
by a Stochastic Approach, Radio Sci., vol. 38, no. 3, 1060, doi:10.1029/2002RS002603.

Goto Y., Y. Kasahara, and T. Sato [2004], An Inversion Technique of the Plasmaspheric Electron
Density Estimation Based on Propagation Characteristics of Whistler Mode Wave, Proceedings of2004 International Symposium on Antennas and Propagation (ISAP 2004), 1E2-2, 245-248.

Hada T., M. oonishi, B. Lembege, and P. Savoini [2003], “Shock front nonstationarity ofsupercritical perpendicular shocks”, J. Geophys. Res., vol.108 (A6), Art. No. 1233.

Han, D., T. Iyemori, Y. Gao, Y. Sano, F. Yang, W. Li, M. Nose [2003], “Local time dependence ofthe frequency of Pi2 waves simultaneously observed at 5 low-latitude stations”, Earth Planets Space,
55, pp.601-612.

Han, D.-S., T. Iyemori, M. Nose, H. McCreadie, Y. Gao, F. Yang, S. Yamashita, P. Stauning [2004],“A comparative analysis of low-latitude Pi2 pulsations observed by Orsted and ground stations”, J.
Geophys. Res.,.vol.109, A10209, doi:10.1029/2004JA010576.

Hashimoto, K., H. Iwai, Y. Ueda, H. Kojima, and H. Matsumoto [2003], “Software wave receiver for
the SS-520-2 rocket experiment”, IEEE Trans. Geosci. Remote Sensing, Vol. 41, No. 11,
pp.2638-2647.

Hayakawa, M. and A. P. Nickolaenko [2001], “Lightning effects in mesosphere and associated ELF
radio signals”, Proc. Indian Nat'l Science Academy, 67, A, No.4 & 5, pp.509-529.

Hayakawa, M. and T. Otsuyama [2002], “FDTD analysis of ELF wave propagation in
inhomogeneous subionospheric waveguide models”, Appl. Computational Electromagnetics Soc. J.,
vol.17, No.3, pp.239-244.

Hayakawa, M. and K. Ohta [2003], “The importance of direction finding technique in general VLF
studies, in “Very Low Frequency (VLF) Phenomena” ”, Ed. by A.R.W. Hughes, C. Ferencz and A.K.
Gwal, pp.22-35, Narosa Pub. House, New Delhi.

Hayakawa, M., O. A. Molchanov, A. Y. Schekotov, and E. Fedorov [2004a], “Observation ofionospheric Alfven resonance at a middle latitude station”, Adv. Polar Upper Atmos. Res., No.18,
pp.65-76.

Hayakawa, M., T. Nakamura, Y. Hobara and E. Williams [2004b], “Observation of sprites over the
Sea of Japan and conditions for lightning-induced sprites in winter”, J. Geophys. Res., vol. 109,
A01312, doi:10.1029/2003JA009905.

Hayakawa, H., Y. Kasaba, H. Yamakawa, H. Ogawa, and T. Mukai [2004],“The

BepiColombo/MMO model payload and operation plan”, Adv. in Space Research, 33, 12,2142-2146.

Higashi, R., T. Imachi, S. Yagitani, and I. Nagano [2004], “Estimation of impedance of wire
antennas onboard the Akebono satellite”, Proceedings of 2004 International Symposium on Antennas
and Propagation (ISAP 2004), Vol.1, pp.269-272, Sendai (Japan).

Higuchi, T., S. I. Ohtani, T. Uozumi, and K. Yumoto [2002], "Pi2 onset time determination withinformation criterion", J. Geophys. Res. 107 (A7): Art. No. 1107.

Hikishima, M., S. Yagitani, I. Nagano, Y. Omura, and H. Matsumoto [2004], “Computer experimentof cyclotron interaction for chorus generation”, 2004 Asia-Pacific Radio Science Conference(AP-RASC 2004), pp.563-566, Qingdao (China).

Hobara, Y., N. Iwasaki, T. Hayashida, M. Hayakawa, K. Ohta, and H. Fukunishi [2001],“Interrelation between ELF transients and ionospheric disturbances in association with sprites andelves”, Geophys. Res. Lett., vol.28, No.5, pp.935-938.

Hobara, Y., M. Hayakawa, K. Ohta and H. Fukunishi [2003], “Lightning discharges in association
with mesospheric optical phenomena in Japan and their effect on the lower ionosphere”, Adv. Polar
Upper Atmos. Res., No.17, pp.30-47.

Hoshino, M. [2001], “Nonthermal particle acceleration in shock front region: Shock surfing
acceleration”, Prog. Theor. Phys. Suppl., 143, pp. 149-181.

Hoshino, M., and N. Shimada [2002], “Nonthermal Electrons at High Mach Number Shocks:

Electron Shock Surfing Acceleration”, Astrophys. J., 572, pp. 880-887.

Hoshino, M., and T. Mukai [2002], “Suprathermal Electons during Magnetic Reconnection: Fermi
Model”, Adv. Space Res., 30, pp.1639-1644.

Hosotani, A., T. Ono, A. Kumamoto, H. Oya [2001], “Propagation modes and source locations of theauroral kilometric radiation (AKR) identified by using the wave distribution function method”,
Advances in Polar Upper Atmosphere Research,, 15, pp.117-127.

Hosotani, A., T. Ono, M. Iizima, A. Kumamoto [2003], “Second harmonics of auroral kilometricradiation observed by the Akebono satellite”, Adv. Polar Upper Atmos. Res., 17, pp.146-154.

Ikeda. M. [2002], “Approximate derivation of self-exciting whistler-mode sideband wave
frequencies”, Indian Journal of Radio & Space Physics, 31, pp. 121-129.

Imachi, T., S. Yagitani, I. Nagano, S. Esaki, R. Higashi, M. Tsutsui, and H. Matsumoto [2004],“Characteristics of electric wire antennas onboard scientific spacecraft”, 2004 Asia-Pacific Radio
Science Conference (AP-RASC 2004), pp.558-561, Qingdao (China).

Imai, K., F. Reyesy, and T. D. Carry [2001], “Modulation lane measurement of Jupiter's Io-b source
parameters”, Planetary Radio Emissions V, edited by H.O. Rucker, M.L. Kaiser and Y. Leblanc,
Austrian Academy of Science Press, Vienna, Austria, pp.119-126,.

Imai, K., J. J. Riihimaa, F. Reyes, and T. D. Carr [2002], “Measurement of Jupiter’s decametricradio source parameters by the modulation lane method”, J. Geophys. Res., 107, NO. A6,
10.1029/2001JA007555

Imhof, W. L., R. R. Anderson, M. Walt, J. D. Hawley, S. M. Petrinec, J. Mobilia, and H. Matsumoto[2003], The dependence of AKR production on the intensity and energy spectra of auroral
bremsstrahlung, J. Geophys. Res., 108(A3), 1099, doi:10.1029/2002JA009274.

Imhof, W. L., S. M. Petrinec, R. R. Anderson, M. Walt, J. Mobilia, and H. Matsumoto[2004],"Correlations between low-frequency and high-frequency auroral kilometric radiation plasma wave
intensity bursts and X rays in the auroral zone", J. Geophys. Res., vol.109, pp.A09204-1-A09204-12.

Ishisaka, K.，T. Okada，H. Hayakawa，T. Mukai and H. Matsumoto [2004], Application of spacecraft
potential to investigate the distribution of low energy plasma in magnetosphere, COSPAR Colloquia
Ser. 16, Frontiers in Magnetospheric Plasma Physics, pp. 75-78.

Kasaba, Y., H. Matsumoto, and Y. Omura [2001], “One- and two-dimensional simulations of electron
beam instability: Generation of electrostatic and electromagnetic 2fp waves”, J. Geophys. Res., 106,
18693-18711.

Kasaba, Y., H. Matsumoto, Y. Omura, and T. Mukai[2004], "2fp Radio source in Geotail
observations and numerical simulations -Microscopic view-", Frontiers of Magnetospheric Plasma
Physics, COSPAR Colloquia Series, vol.16, pp.247-250.

Kasahara, Y., H. Matsumoto, and H. Kojima [2001], "Type III Solar Radio Bursts in the
Inhomogeneous Interplanetary Space Observed by GEOTAIL", Radio Science, 36(6), pp.1701-1711.

Kasahara Y., Niitsu R., and Sato T. [2002], “Computational Analysis of Plasma Waves and Particles
in the Auroral Region Observed by Scientific Satellites”, Progress in Discovery Science, LNCS,
Springer, 2281, pp.426-437,.

Katoh, Y., H. Oya, M. Iizima, and T. Ono [2003],

Numerical study on the spatial extent ofinteraction region surroundings comet nucleus - Ion pick-up process , Earth Planets Space, vol.55,
pp.705‐711.

Katoh, Y. and Y. Omura [2004], "Acceleration of relativistic electrons due to resonant scattering by
whistler mode waves generated by temperature anisotropy in the inner magnetosphere", J. Geophys.
Res., vol.109, A12214, doi:10.1029/2004JA010654.

Kawano, H, K. Yumoto, V. A. Pilipenko, Y. M. Tanaka, S. Takasaki, M. Iizima, and M. Seto [2002],"Using two ground stations to identify magnetospheric field line eigenfrequency as a continuousfunction of ground latitude", J. Geophys. Res., 107 (A8): Art. No. 1202.

Kobayashi, T., H. Oya, and T. Ono [2002a], “A-scope analysis of subsurface radar sounding of lunar
mare region”, Earth Planets Space, Vol.54, pp.973-982,.

Kobayashi, T., H. Oya, and T. Ono [2002b], B-scan analysis of subsurface radar sounding of lunar
highland region, Earth Planets Space, Vol.54, pp.983-991..

Kosaka, K., T. Iyemori, M. Nose, M. Bitterly, J. Bitterly [2002], “Local time dependence of thedominant frequency of Pi2 pulsations at mid- and low-latitudes”, Earth Planets Space, Vol.54,
pp.771-781.

Krasovsky, V. L., H. Matsumoto, and Y. Omura [2002], "Approximate invariant of electron motionin the field of a whistler propagating along the geomagnetic field", Geophys. Res. Lett., vol.29,
pp.20-1-20-4

Krasovsky, V. L., H. Matsumoto, and Y. Omura [2003], "Electrostatic solitary waves as collective
charges in a magnetospheric plasma: Physical structure and properties of Bernstein-Greene-Kruskal(BGK) solitons", J. Geophys. Res., vol.108, pp.SMP 12-1-SMP 12-19.

Krasovsky, V. L.,H. Matsumoto, and Y. Omura [2004], "Effect of trapped-particle deficit andstructure of localized electrostatic perturbations of different dimensionality", J. Geophys. Res.,
vol.109, No. A4, A04217, 10.1029/2003JA010198.

Kumamoto, A., T. Ono, and H. Oya [2001], “Seasonal dependence of the vertical distributions ofauroral kilometric radiation sources and auroral particle acceleration regions observed by the
Akebono satellite”, Adv. Polar Upper Atmos. Res., 15, pp.32-42.

Kumamoto, A., T. Ono, M. Iizima, and H. Oya [2003a], "Seasonal and solar cycle variations of thevertical distribution of the occurrence probability of auroral kilometric radiation sources and of
upflowing ion events", J. Geophys. Res., 108(A1), 1032, doi:10.1029/2002JA009522.

Kumamoto, A., T. Ono, M. Iizima, H. Oya [2003b], “Control factor of solar cycle variation ofauroral kilometric radiation”, Adv. Polar Upper Atmos. Res., 17, pp.48-59.

Lembege B., J. Giacalone, M. Scholer, T. Hada, M. Hoshino, V. Krasnoselskikh, H. Kucharek, P.
Savoini, and T. Terasawa [2004], "Selected problems in collisionless-shock physics", Space Sci. Rev.,
vol.110, pp.161-226.
Matsukiyo S., and T. Hada [2002],
relativistic ring distribution

Nonlinear evolution of electromagnetic waves driven by the, Physics of Plasmas, vol.9, pp.649-661.

Matsukiyo S, and T. Hada [2003], “ Parametric instabilities of circularly polarized Alfven waves in a
relativistic electron-positron plasma” Phys. Rev., vol.E67 (4), Art. No. 046406 Part 2.

Matsukiyo, S., R. A. Treumann, and M. Scholer [2004], "Coherent waveforms in the auroral upward
current region", J. Geophys. Res., vol.109, A06212, doi:10.1029/2004JA010477.

Matsuoka, H., A. S. Yukimatu, H. Yamagishi, N. Sato, G. J. Sofko, B. J. Fraser, P. Ponomarenko, R.
Liu, and T. Goka [2002], "Coordinated observations of Pc3 pulsations near cusp latitudes", J.
Geophys. Res., 107 (A11): Art. No. 1400.

Matsumoto, H., X. H. Deng, H. Kojima, and R. R. Anderson[2003], "Observation of electrostatic
solirtary waves associated with reconnection on the dayside magnetopause boundary", Geophys. Res.
Lett., vol.30, pp.59-1-59-4.

Menietti, J. D., R. R. Anderson, J. S. Pickett, D. A. Gurnett, and H. Matsumoto [2003], “Near-source
and remote observations of kilometric continuum radiation from multispacecraft observations”, J.
Geophys. Res., 108(A11), 1393, doi:10.1029/2003JA009826, 2003.

Miyake, T., T. Okada, J. Miyakawa, D. Tomishima, K. Ishisaka, H. Kojima, Y. Ueda, H. Matsumoto[2003], “Analysis of DC electric fields observed by SS-520-2 sounding rocket in the polar region”,
IEICE Trans. on Communication B, vol.J86-B, No.6, pp.236-244. (in Japanese)

Miyake, T., T. Okada, H. Yamagishi, A. Chino, K. Ishisaka, T. Yamagami [2004], “Development of
ELF/VLF band wave receiver onboard Polar Patrol Balloon”, IEICE Trans. on Communication B,
vol.J87-B, No.5, pp.741-745.

Miyoshi, Y., A. Morioka, T. Obara, H. Misawa, T. Nagai, and Y. Kasahara, [2003], “Rebuilding
process of the outer radiation belt during the November 3, 1993, magnetic storm-NOAA and
EXOS-D observations-“, J. Geophys. Res., 108, SMP 3-1, 1004, DOI 10.1029/2001JA007542.

Molchanov, O. A., M. Hayakawa, and K. Miyaki [2001], “VLF/LF sounding of the lower ionosphereto study the role of atmospheric oscillations in the lithosphere-ionosphere coupling”, Adv. Polar
Upper Atmos. Res., No.15, pp.146-158.

Morioka, A., F. Tsuchiya, Y. Miyoshi, H. Misawa, H. Oya, and K. Furukawa [2002], “Duration of
Jovian magnetospheric disturbances inferred from decametric radio storms”, Earth, Planets andSpace, 54, 1277-1281.

Morioka, A., Y. Miyoshi, T. Seki, F. Tsuchiya, H. Misawa, H. Oya, H. Matsumoto, K. Hashimoto, T.
Mukai, K. Yumoto, and T. Nagatsuma [2003], “AKR disappearance during magnetic storms”, J.
Geophys. Res., 108, SMP 3-1, 1226, DOI 10.1029/2002JA009796.

Morioka, A., T. Yuasa, Y. S. Miyoshi, F. Tsuchiya, and H. Misawa [2004], “Source characteristics
and radiation mechanism of Jovian anomalous continuum”, J. Geophys. Res., 109, A06206,
doi:10.1029/2004JA010409.

Morooka, M., M. Andre, J.-E. Wahlund, S. C. Buchert, A. N. Fazakerley, J. D. Winningham, H.
Reme, I. Dandouras, B. Lavraud, A. Balogh, K. Igenbergs [2004], “Cluster observations of ULF
waves with pulsating electron beams above the high latitude dusk-side auroral region”, Geophys.
Res. Lett., Vol.31, L05804, doi:10.1029/2003GL017714.

Motoba, T., T. Kikuchi, H. Luhr, H. Tachihara, T. I. Kitamura, K. Hayashi, and T. Okuzawa [2002],"Global Pc5 caused by a DP 2-type ionospheric current system", J. Geophys. Res., -Space Physics
107 (A2):Art. No. 1032.

Motoba, T., T. Kikuchi, T. Okuzawa, and K. Yumoto [2003], "Dynamical response of themagnetosphere-ionosphere system to a solar wind dynamic pressure oscillation", J. Geophys Res.,108 (A5): Art. No. 1206.

Motoba, T., T. Kikuchi, T. F. Shibata, and K. Yumoto [2004], "HF Doppler oscillations in the
low-latitude ionosphere coherent with equatorial long-period geomagnetic field oscillations", J.
Geophys. Res., 109 (A6): 1-7 .

Murata. K. T., M. Okada, F. Abe, T. Araki and H. Matsumoto [2002a], “A Design and Estimation ofDistributed Meta-database for Solar-terrestrial Physics Observation Data”, IPSJ Trans. on Databases,
Vol.43, No.SIG12 (TOD16), pp.115-130

Murata, K. T., K. Ueoka, S. Takahashi, M. Okada, Hiroko O. Ueda, Y. Omura and H. Matsumoto[2002b], “A Parallel Computing Method for Plasma Particle Simulation Code, IPSJ Transactions onMathematical Modeling and Its Applications”, Vol.43, No.SIG7 (TOM6), pp.118-131.

Murata, K. T., Hiroko O. Ueda, K. Ueoka, H. Usui, M. Okada, Y. Omura and H. Matsumoto [2002c],“An Object-oriented Plasma Particle Simulation Code Developed via Object Modeling Technique”,
The IEICE Transactions on Communications (B), Vol.J85-B, No.8, pp.1411-1425.

Murata, K. T. [2002d], “A Problem Solving Environment for Space Plasma Simulations:
PocketPOM”, The IEICE Transactions on Communications (B), Vol.J85-B, No.4, pp.573-578..

Murata, K. T., Nurdiyana B. A. Gahni, H. Usui, Hiroko O. Ueda, M. Okada, Y. Omura and H.
Matsumoto [2002e], “A Problem Solving Environment for Space Plasma Computer Simulations”,
IPSJ Trans. on Mathematical Modeling and Its Applications, Vol.43, No.SIG7(TOM6), pp.105-117.

Murata, K. T. [2003], “A World-wide Distributed Database System for ISTP Project”, The IEICE
Trans. on Communications (B), Vol.7, No.J86-B, pp.1331-1343.

Murata, K. T., W. Kurth, K. Hshimoto, and H. Matsumoto [2004a], "Occultations of Auroral
Kilometric Radiation in the Vicinity of the Earth", Frontiers of Magnetospheric Plasma Physics,
COSPAR Colloquia Series, vol.16, pp.220-223.

Murata, K. T., Nurdiyana B. A. Gahni, K. Hashimoto, H. Matsumoto and T. Ogino [2004b],“Proposal of a Virtual Earth Magnetosphere System”, The IEICE Trans. on Communications (B),Vol.J87-B, No.2, pp.309-313.

Nagano, I., X.-Y. Wu, H. Takano, S. Yagitani, H. Matsumoto, K. Hashimoto, and Y. Kasaba[2003a],"Remote sensing the magnetosheath by the spin modulation of terrestrial continuum
radiation", J. Geophys. Res., vol.108, no.A6, 1224, doi:10.1029/2002JA009691, SMP1-1 - 1-7.

Nagano, I., S. Yagitani, K. Miyamura, and S. Makino [2003b], "Full wave analysis of elves createdby lightning-generated electromagnetic pulses", J. Atmos. Solar-Terr. Phys., vol.65, no.5,
pp.615-625.

Nakagawa, T., Y. Takahashi, and M. Iizima [2003], "GEOTAIL observation of upstream ULF waves
associated with lunar wake", Earth Planets Space 55, (9): 569-580 2003.

Nakajo, T., T. Ono, M. Iizima, M. Oya, and H. Oya [2001], “Evaluation of the double frequency
interferometer method applied for the long baseline observations of the Jovian decametricradiations”, Technology Development Center News, 19, pp.19-24.

Nickolaenko, A. P., L. M. Rabinowicz, and M. Hayakawa [2004a], “Time domain presentation for
ELF pulses with accelerated convergence”, Geophys. Res. Lett., vol.31, L05808, doi:10.1029/2003GL018700.

Nickolaenko, A. P., L. M. Rabinowicz, and M. Hayakawa [2004b], “Natural ELF pulses in the time
Domain : Series with accelerated convergence”, IEEJ Trans. Fundamentals and Materials, vol.124,
No.12, pp.1210-1215.

Nickolaenko, A. P., S. O. Nikolayenko, Yu. Schekotov, and M. Hayakawa [2004c], “Alternativeinterpretation of ionospheric Alfven resonance”, J. Atmos. Electr., 24, pp.17-30.

Nishimura, K., H. Matsumoto, and H. Kojima [2002], "Electron acceleration and heating influenced
by whistler wave packets at quasi-parallel shock waves", J. Geophys. Res., vol.107, pp.7-1-7-11.

Nishimura, K, H. Matsumoto, H. Kojima, and S. P. Gary [2003], "Particle simulations of
re-formation at collisionless perpendicular shocks: Coherent behavior of reflected ions", J. Geophys.
Res., vol.108, pp.SSH 3-1-SSH3-5.

Nose, M., K. Takahashi, T. Uozumi, K. Yumoto, Y. Miyoshi, A. Morioka, D. K. Milling, P. R.
Sutcliffe, H. Matsumoto, T. Goka, H. Nakata [2003], “Multipoint observations of a Pi2 pulsation onmorningside: The 20 September 1995 event”, J. Geophys. Res., Vol.108(A5), 1219,
doi:10.1029/2002JA009747.

Obara, T., Y. Miyoshi and A.Morioka [2001], “Large Enhancement of the Outer Belt Electrons
during Magnetic Storm”, Earth Planets Space, (53), pp.1163-1170.

Obara, T. and X. Li [2003], “Formation of New Electron Radiation Belt During MagnetosphericCompression Event”, Adv. Space Res., (31), No.4, pp1027-1031.

Okada, T., S. Yagitani, I. Nagano, T. Imachi, M. Mukaino,

Y. Kasaba, and H. Matsumoto [2001],“Propagation characteristics of ELF/VLF electromagnetic waves in the Martian ionosphere and thepossibility for detection of Martian atmospherics by NOZOMI observations", Trans. IEICE, E84-B,
3. pp.653-659.

Okada, T., H. Maeda, T. Miyake, K. Ishisaka, K. Turuda, [2004], “Study on EM noises around asatellite and their control based on FDTD simulation”, Trans. IEICE, Vol.J86-B, No.8, pp.1119-1123.

Omura, Y., W. J. Heikkila, T. Umeda, K. Nimomiya, and H. Matsumoto [2003], "Particle simulation

of plasma response to an applied electric field parallel to magnetic field lines", J. Geophys.
Res.,Vol.108(A5), 1197,doi:10.1029/2002JA009573.

Omura, Y., and D. Summers [2004], “Computer simulations of relativistic whistler-mode
wave-particle interactions”, Phys. Plasmas, Vol. 11, no. 7, pp. 3530-3534.

Otsuka, F., and T. Hada [2003],
field turbulence

Cross field diffusion of cosmic rays in a two-dimensional magnetic, Space Sci. Rev., vol.107, pp.499-502.

Otsuyama, T. and M. Hayakawa [2002], “FDTD simulation and experimental result on VLF
scattering by ionospheric perturbations in Earth-ionosphere waveguide”, Trans. IEE Japan,
vol.122-A, No.1, pp.59-64.

Otsuyama. T., T. Kariya and M. Hayakawa [2003a], “VLF signatures of ionospheric perturbation in
the Hokuriku area of Japan”, Adv. Polar Upper Atmos. Res., No.17, pp.109-119.

Otsuyama, T., D. Sakuma and M. Hayakawa [2003b], “FDTD analysis of ELF wave propagation andSchumann resonance for a subionospheric waveguide model”, Radio Sci., vol.38, No.6, 1103,
doi:10.1029/2002RS002752.

Otsuyama, T. and M. Hayakawa [2004], “FDTD analysis of ELF wave propagation for realistic

subionospheric waveguide”, IEEJ Trans. Fundamentals and Materials, vol.124, No.12, p.1203-1209.

Otsuyama, T., J. Manaba, M. Hayakawa, and M. Nishimura [2004a], “Characteristics ofsubionospheric VLF perturbation associated with winter lightning around Japan”, Geophys. Res.
Lett., vol. 31, L04117, doi:10.1029/2003GL019064.

Otsuyama, T., J. Manabe and M. Hayakawa [2004b], “Characteristics of subionospheric VLF
perturbations associated with winter lightning around Japan”, Adv. Polar Upper Atmos. Res., No. 18,
pp.77-86.

Oya, M., T. Ono, M. Iizima, and H. Oya [2001a], “Location of the acceleration region of thebunched electrons inferred from the interaction event of S-bursts with L-bursts and N-bursts”,
Planetary Radio Emission 5 edited by H.O. Ruckers, M.L. Kaiser and Y. Leblanc,Verlag derOsterreichichen Akademie der Wissenschaften, Wien, Austria, pp.105-112.

Oya, M. T. Nakajo, S. Konno, T. Ono, M. Iizima, and H. Oya [2001b], Development of an array
antenna system and a multi-frequency interferometer network for the Jovian decametric radiation,
Planetary Radio Emission 5 edited by H.O. Ruckers, M.L. Kaiser and Y. Leblanc, Verlag derOsterreichichen Akademie der Wissenschaften, Wien, Austria, pp.210-218.

Oya, M., H. Oya, T. Ono, and M. Iizima [2002], “Analysis of Jovian decametric radiation S-bursts
interacting with N-bursts”, Earth, Moon and Planets, 88, pp.187-209.

Oya, H., and M. Iizima[2003], “Mapping of the decameter radio sources ofCassiopeia A using a

100km range long-baseline interferometer:Verification of a new method of phase calibration ofinterferometers”, Publ. Astron. Soc. Japan, 55, 527-534.

Ozaki, M., I. Nagano, S. Yagitani, and K. Miyamura [2004], "Ionospheric propagation of ELF/VLF
waves radiated from earthquake", 2004 Asia-Pacific Radio Science Conference Proceedings(AP-RASC 2004), pp.539-542.

Saka, O., H. Akaki, and D. N. Baker [2002], "A satellite magnetometer observation of dusk-to-dawn
current in the midnight magnetosphere at low-latitude Pi2 onset", Earth Planets Space 54 (12):E1-E4.

Saka, O., H. Akaki, and D. N. Baker [2004], "A Pi2-associated dusk-to-dawn currents in themidnight sector as observed at L-6.6 during multiple Pi2 onsets", Earth Planets Space 56 (7):pp.663-668.

Sakurai, T., Y. Tonegawa, and Y. Shinkai [2001], “Poynting vectors of Pc 5 pulsations observed by
the GEOTAIL satellite in the dayside outer magnetosphere”, Earth Planets Space, 53, pp.843-849..

Sato, N., D. M. Wright, C. W. Carlson, Y. Ebihara, M. Sato, T. Saemundsson, S. E. Milan, and M.
Lester [2004], “Generation region of pulsating aurora obtained simultaneously by the FAST satellite
andaSyowa-Iceland

conjugate

pair

of

observatories”,

J.

Geophys.

Res.,

109,

doi:10.1029/2004JA0104192004.

Shimada, N., and M. Hoshino [2003], “Electron-Ion Coupling Dynamics in the Shock Transition
Region”, Phys. Plasma , 10, pp.1113-1119.

Shimada, N., and M. Hoshino [2004], “Electron heating and acceleration in the shock transition
region: Background plasma parameter dependence”, Phys. Plasma, 11, 1840.

Shin, K.,H. Kojima, H. Mtsumoto, and T. Mukai [2004], "Electrostatic Quasi-monochromatic Waves
Downstream of the Bow Shock: GEOTAIL Observations", Frontiers of Magnetospheric Plasma
Physics, COSPAR Colloquia Series, vol. 16, pp.293-296.

Shinbori, A., T. Ono, and H. Oya [2002], “SC triggered plasma waves observed by the Akebono
satellite in the polar regions and the Plasmasphere”, Adv. Polar Upper Atmos. Res., No.16,
pp.126-135.

Shinbori, A., T. Ono, M. Iizima, A. Kumamoto, H. Oya [2003a], “SC Related Kilometric and
Hectometric Radiations Observed by the Akebono Satellite in the Polar Regions”, Adv. Polar Upper
Atmos. Res., 17, 60-76.

Shinbori, A., T. Ono, M. Iizima, A. Kumamoto and H. Oya [2003b], “SC Related Plasma Waves
Observed by the Akebono Satellite in the Polar Region and inside the Plasmasphere Region”, J.
Geophys. Res., vol.108, No. A12, 1457, doi:10.1029/2003JA009964.

Shinbori, A., T. Ono, M., Iizima and A. Kumamoto [2004], “SC related electric and magnetic field
phenomena observed by the Akebono satellite inside the plasmasphere”, Earth Planets Space, 56,
pp.269–282.

Shiokawa, K., K. Yumoto, and J. V. Olson [2002], "Multiple auroral brightenings and associated Pi 2
pulsations", Gephys. Res.,Lett 29 (11): Art. No. 1537.

Shklyar, D. R. and H. Matsumoto [2002], "Dynamics of a wave-pulse penetration into evanescentregion", Physical Review E, vol.66-046612, pp.1-11.

Singh, B. and M. Hayakawa [2001], “Propagation modes of low- and very-low-latitude whistlers”, J.
Atmos. Solar-terr. Phys., vol.63, pp.1133-1147.

Singh, B. and M. Hayakawa [2003], “Propagation modes of low and very low latitude whistlers,“Very Low Frequency (VLF) Phenomena” ”, Ed. by A.R.W. Hughes, C. Ferencz and A.K. Gwal,
pp.174-199, Narosa Pub. House, New Delhi.

Singh, B., M. Hayakawa, P. K. Mishra, R. P. Singh and D. R. Laskshmi [2003], “VLF
electromagnetic noise bursts observed in a borehole and their relation with low-latitude hiss”, J.
Atmos. Solar-terr. Phys., vol.65, pp.269-276.

Soloviev, O. V. and M. Hayakawa [2002], “Three-dimensional subionospheric VLF field diffraction
by a truncated highly conducting cylinder and its application to the Trimpi effect problem”, Radio
Sci., Vol. 37, No. 5, 1079, doi:10.1029/2001RS002499

Soloviev, O. V. and M. Hayakawa [2004], “3D modeling method of VLF subionospheric radio wave
propagation allowing for a localized ionospheric perturbation”, IEEJ Trans. Fundamentals andMaterials, vol. 124, No. 12, pp.1216-1224.

Sugiyama, T.,

N. Terada, Ken T. Murata, Y. Omura, H. Usui and H. Matsumoto [2004],“Vectorized Particle Simulation Using "LISTVEC" Compile-directive on SX Super-computer”, IPSJ
Trans. on Advanced Computing Systems, Vol.45, No.SIG6(ACS6), pp.171-175.

Takano, H., I. Nagano, S. Yagitani, M. Fukuoka, and H. Matsumoto [2001], “Propagation
Characteristics of Lobe Trapped Continuum Radiation in the Distant Magnetotail”, Trans. IEICE,
vol.J84-B, no.12, pp.2358-2366.

Takano, H., I. Nagano, and S. Yagitani [2003], “Analysis of Electromagnetic Wave Propagation
with Resonance Effect in Collision-Free Magnetized Plasma”, Trans. IEICE, vol.J86-B, no.7,
pp.1298-1307.

Takano, H., I. Nagano, S. Yagitani, and H. Matsumoto[ 2004], “Lobe trapped continuum radiation
generated in the distant magnetotail”, Frontiers in Magnetospheric Plasma Physics (COSPAR
Colloquia Series, Vol.16), M. Hoshino, Y. Omura, and L. J. Lanzerotti (eds.), pp.224-227, Elsevier,
2004.

Takata Y., Y. Kasahara, S. Tanaka, M. Obayashi [2004], “Construction of an Enormous Science
Database and Development of an Efficient Data Retrieval and Distribution System (in Japanese)”, J.
Acad. Computing and Networking, Vol.8, pp.33-43.

Takeuchi, T, T. Araki, A. Viljanen, and J. Watermann [2002a], "Geomagnetic negative sudden
impulses: Interplanetary causes and polarization distribution", J. geophys. Res., 107 (A7): Art. No.
1096.

Takeuchi T, C. T. Russell, and T. Araki [2002b], "Effect of the orientation of interplanetary shock on
the geomagnetic sudden commencement",

J. Geophys. Res., 107 (A12): Art. No. 1423..

Tanaka, Y. M., K. Yumoto, A. Yoshikawa, M. Shinohara, H. Kawano, and T. I. Kitamura [2004],"Longitudinal structure of Pc3 pulsations on the ground near the magnetic equator", J. Geophys. Res.,-Space Physics 109 (A3): Art. No. A03201 MAR 3 2004.

Terada, N., S. Machida, and H. Shinagawa [2002], “Global hybrid simulation of the
Kelvin–Helmholtz instability at the Venus ionopause”, J. Geophys. Res., vol.107, No. A12,
10.1029/2001JA009224.

Terada N, H. Shinagawa, and S. Machida [2004],

Global hybrid model of the solar windinteraction with the Venus ionosphere: ion escape processes , Adv. Space Res., vol.33, pp.161-166.

Trakhtengerts, V. Y., Y. Hobara, A. G. Demekhov, and M. Hayakawa [2001], “A role of thesecond-order cyclotron resonance effect in a self-consistent approach to triggerd VLF emissions”, J.
Geophys. Res., 106, pp.3897-3904.

Trakhtengerts, V. Y., D. I. Iudin, A. V. Kulchitsky, and M. Hayakawa [2002], “Kinetics of runaway
electrons in a stochastic electric field”, Phys. Plasmas, 9, pp.2762-2766.

Trakhtengerts, V. Y., D. I. Iudin, A. V. Kulchitsky, and M. Hayakawa [2003a], “Electron acceleration
by a stochastic electric field in the atmospheric layer”, Phys. Plasma, 10, pp.3290-3296.

Trakhtengerts, V. Y., A. G. Demekhov, Y. Hobara, and M. Hayakawa [2003b], “Phase-bunchingeffects in triggered VLF emissions: Antenna effect”, J. Geophys. Res., 108(A4), 1160,
doi:10.1029/2002JA009415.

Tsurutani, B., G. S. Lakhina, J. S. Pickett, and Y. Kasahara [2003], “ELF/VLF Plasma Waves in the
Low Latitude Boundary Layer”, American Geophysical Union Monogr., vol.133, pp.189-203.

Tsutsui, M. [2002], Detection of earth-origin electric pulses, Geophys. Res. Letts., Vol. 29, No.8,
10.1029/2001GL013713.

Ueda, Y., H. Kojima, H. Matsumoto, K. Hashimoto, I. Nagano, T. Okada, and T. Mukai [2003],

“Lower hybrid waves observed at the dayside polar region: SS-520-2 rocket experiment”, Radio Sci.,
vol.38, pp.6-1-6.

Uemoto, J., T. Ono, A. Kumamoto, and M. Iizima [2004], “Ionization ledge structures observed in
the equatorial anomaly region by using PPS system on-board the Ohzora (EXOS-C) satellite”, Earth
Planets Space, 56, e21-e24.

Umeda. T., Y. Omura, H. Matsumoto, and H. Usui [2002], "Formation of electrostatic solitary waves
in space plasmas: Particle simulations with open boundary", J. Geophys. Res., vol.107, pp.SMP
19-1-SMP 19-16.

Umeda, T., Y. Omura, P. H. Yoon, R. Gaelzer, and H. Matsumoto [2003], "Harmonic Langmuir
waves: III. Vlasov simulation", Physics of Plasmas, vol.10, pp.382-391.

Umeda, T., Y. Omura, and H. Matsumoto[2004], "Two-dimensional particle simulation ofelectromagnetic field signature associated with electrostatic solitary waves", J. Geophys. Res.,
vol.109, pp.A02207-1-A02207-10.

Uozumi, T., K. Yumoto, H. Kawano, A. Yoshikawa, S. Ohtani, J. V. Olson,S. I. Akasofu, S. I.
Solovyev, E. F. Vershinin, K. Liou, and C. I. Meng [2004], "Propagation characteristics of Pi 2
magnetic pulsations observed at ground high latitudes", J. Geophys. Res., 109 (A8): Art. No. A08203
AUG 13 2004.

Usui, H., H. Matsumoto, R. Gendrin, and T. Nishikawa [2002], "Numerical simulations of athree-wave coupling occurring in the ionospheric plasma", Nonlinear Processes in Geophysics, vol.9,
pp.1-10.

Usui, H., H. Matsumoto, F. Yamashita, A. Yamamoto and Y. Omura [2004a], "Antenna analysis inmagnetized plasma via particle-in-cell simulation", Advances Space Res., vol.34, pp.2433-2436.

Usui, H., H. Matsumoto, Y. Yasugi, H. Tashima and Y. Omura [2004b], "PIC simulations ofspacecraft charging and the neutralization process by plasma emission", Adv. Space Research, vol.34,
pp.2437-2440.

Usui, H., H. Matsumoto, K. Miyata and Y. Omura [2004c], "Computer experiments onelectromagnetic environment of plasma sheath at conducting surface", Adv. Space Research, vol.34,

pp.2441-2444.

Yamaguchi, R., H. Kawano, S. Ohtani, K. Yumoto, T. Mukai, Y. Saito, and H. Hayakawa [2002],"The timing relationship between bursty bulk flows and Pi2s at the geosynchronous orbit", Gephys.
Res. Lett., 29 (6): Art. No. 1092 MAR 15 2002.

Yamakawa, H., H. Ogawa, Y. Kasaba, H. Hayakawa, T. Mukai, and

A. Adachi [2002], “ISAS

feasibility study on the BepiColombo/MMO spacecraft design”, Acta Astronautica, 51, 1,
pp.397-404,.

Yamakawa, H., H. Ogawa, Y. Kasaba, H. Hayakawa, T. Mukai, and M. Adachi [2004], “Current
status of the BepiColombo/MMO spacecraft design”, Adv. Space Res., 33, 12, pp.2133-2141.

Yoon, P. H., R. Gaelzer, T. Umeda, Y. Omura, and H. Matsumoto [2003], "Harmonic Langmuir
waves: I. Nonlinear dispersion relation", Physics of Plasmas, vol.10, pp.364-372.
Yoshikawa, A., Y. Obana, M. Shinohara, M. Itonaga, and K. Yumoto [2002], “Hall-induced inductive
shielding effect on geomagnetic pulsations”, Geophys. Res. Lett., vol. 29, no. 8, 1266,
doi:10.1029/2001GL013610, 2002.

Yumoto, K., and the CPMN Group [2001], “Characteristics of Pi 2 magnetic pulsations observed at
the CPMN stations: A review of the STEP results”, Earth Planets Space, 53, 981-992.

Acknowledgements
We would like to thank the following persons for their contributions to this national report ofJapanese Commission H: Masashi. Hayakawa, Hideaki Kawano, Toshihiko Iemori, Shinobu
Machida, Yasumasa Kasaba, Akira Morioka, Takayuki Ono, Hirotsugu Kojima, Kozo Hashimoto,
Hideyuki Usui, Tadasu Nakamura, Yoshiya Kasahara, Satoshi Yagitani, Takeshi Murata, andTaketoshi Miyake.