Edited by Hiroshi Matsumoto and Isamu Nagano

H1. Observation of Space Plasma Waves and Related Phenomena

H1.1. Wave Probing of Space Plasmas

Nighttime strength of MF broadcasting signals (774/770 kHz) transmitted from Japan, along a line bound from Japan to Antarctica revealed a positive correlation with solar activity, which is different from the results in NorthAmerica. Kohata et al. [1990] tried to theoretically elucidate the difference by an existence of a density ledge in the lower ionosphere.

Preliminary results of ionospheric E region observations by MU radar at 46.5 MHz were presented. A comparison was made between the variations of electron density for a normal day and for a partial eclipse with a duration of 3 hours on September 23, 1987. A decrease of 20% in electron density was observed during the eclipse. [Zhang et al., 1991]

H1.2. Hydromagnetic and ULF Wave Phenomena

The statistical dependence of the occurrence rate of polarization (left-handed, right-handed, and linear) of Pc 1 pulsations on local time and wave frequency was deduced on the basis of the data observed in Iceland and in Antarctica. [Hayakawa et al., 1992a]

The polarization of IPDP pulsations at a few stations in Iceland and inthe Antarctica, was examined extensively, and it was found that the information on polarization would be of great use in the study of their generation mechanism. [Hayakawa et al., 1992b]

H1.3. ELF/VLF Wave Phenomena

A review of mid-latitude and plasmaspheric hiss-type emissions observed on ground-based stations and in the magnetosphere, was presented, and different approaches to modeling of these emissions were discussed. [Hayakawa andSazhin, 1992]

A review was made on the results of investigation on low- and very-low-latitude whistlers on the basis of the ground and satellite observations of both natural whistlers and VLF transmitter signals. Also, the measurements of electron density and electric field in the inner plasmasphere were discussed. [Hayakawa and Ohta, 1992a]

The L dependence of whistler-triggered VLF emissions was studied on the basis of the wide-band observations made in Australia, and it was found thatthose whistler-triggered emissions take place in the L range from 1.7 to 2.7,with the maximum occurrence at L=2.1 to 2.3. [Hayakawa and Ohta, 1992b]

A review was presented on chorus emissions observed on ground-based stations and in the Earth's magnetosphere, and future problems to be solved,were suggested. [Sazhin and Hayakawa, 1992]

Methods of diagnostics of magnetospheric parameters based on the analysis of ground-based whistler dynamic spectra and the results of these diagnostics were reviewed. [Sazhin et al., 1992]

VLF data from the low-altitude Ariel 4 satellite were used to investigate the characteristics of low- and equatorial-latitude VLF radio noises. Since the low-latitude radio noises are very impulsive, are localized to the longitudes of thunderstorm centers and exhibit strong diurnal variations, it was concluded that they are generated by lightnings. [Hayakawa, 1989]

The direction finding measurement for low-latitude whistlers yielded that there is no frequency dependence of their direction of arrival, which suggested strongly the ducted propagation for them. [Ohta et al., 1989]

Periodicities in the occurrence of natural chorus emissions at L=2.8, were studied by means of the autocorrelation analysis, and it was found that there exists no conspicuous periodicity related with the two-hop whistler-mode groupdelay. [Hattori and Hayakawa, 1989]

VLF/ELF hiss was found to be generally considered as a Gaussian, stationary random signal, but it includes some kinds of structures such as coherent components. [Tsuji et al., 1989]

The off-equatorial direction finding was carried for the data observed on GEOS 1 satellite, with a special reference to the previous equatorial direction finding, and it was found that the rising-tone chorus is generated with small theta angles near the equator and then propagates in non-ducted mode.[Hayakawa et al., 1991a]

The correlation of occurrence rate of whistlers at Yamaoka (geomag. lat.25 degrees) with thunderstorm activity near its conjugate region and also with solar activity, yielded that the ionospheric absorption is of major importance in the long-term variation of whistler rate, with the duct formation being of secondary effect, while the lightning activity is only a necessary condition.[Ohta and Hayakawa, 1990]

The system of a systematic direction finding on board the Aureol-3satellite was described, in which the simultaneous measurement of five field components was carried out in a frequency range form 10Hz to 1.5kHz.[Hayakawa et al., 1990]

On the basis of the detailed spectral analyses and direction finding data,it was found that a wavelet near the upper edge of the hiss band is responsible for triggering a chorus through coherent wave-particle interaction. [Hattori et al., 1991a]

The analyses of periodicities in whistler occurrence rate yielded that there are a major peak just below 2h and minor peak at about 4h, indicating a cyclic formation of ducts. The long periods of the order of days may be due to the modulation by planetary waves. [Shimakura et al., 1991]

The morphological properties of whistler-triggered emissions were studied on the basis of VLF data at Moshiri during 1976 to 1985, and it was found that the occurrence L shell is localized in two regions: one in L=2.1 to 3.4 (electron slot region) and the other is just around L=1.6 (inner radiation belt). [Hayakawa, 1991a]

The role of hiss in triggering chorus was investigated on the basis of the spectral analysis and direction finding for the Geos satellite data, and some wavelets (coherent wave components) in the hiss band are able to phase-bunch the resonant electrons, leading to the generation of a chorus. [Hattori et al., 1991b]

Direction finding results for different kinds of VLF/ELF emissions were reviewed in order to discuss their generation mechanisms. The plasma waves treated were, (1) half-gyrofrequency VLF emissions, (2) ELF hiss in a detached plasma region, (3) plasmaspheric ELF hiss, and (4) VLF chorus. [Hayakawa, 1991b]

Spaced direction finding measurements of very-low-latitude whistlers were carried in South China, and it was found that such very-low-latitude whistlers are attributed to the trapped propagation in field-aligned irregularities. [Hayakawa et al., 1991b]

The direction finding yielded that there is no frequency dependence on the ionospheric exit points of low-latitude whistlers and their polarization, and this supports the ducted propagation for them. [Ohta et al., 1991]

The triggering of chorus from wavelets in the hiss band was furthermore confirmed by the additional data analyses. [Hattori et al., 1991c]

The electrostatic ion cyclotron emissions were investigated on the basis of the data observed by Isis, Kyokko and Akebono satellites, and also their relation to auroral emissions was studied. [Yoshino, 1991]

A polar map of the occurrence rate of auroral hiss for Kp=0-7 obtained from ISIS VLF electric field data is approximately symmetric with respect to the 10-22 geomagnetic local time (MLT) meridian and it has the high latitude limit of 82 degrees for all local times. Its low latitude limit is 67 degrees around 22 MLT and 74 degrees around 10 MLT. The polar map of the hiss is qualitatively similar to the polar location map of inverted-V electron precipitation observed by AE-D. [Ondoh, 1990]

The polar map of polar hiss (so-called the auroral hiss) for Kp=0-1 also shows the axial symmetry of the 10-22 hour MLT meridian and its low latitude boundary is higher than that in various geomagnetic conditions. The map of polar hiss is different from the auroral zone with the noon-midnight symmetry meridian. The frequency range of the downgoing polar hiss seems to be the whistler mode Cherenkov radiation generated from inverted-V electrons in the polar magnetosphere. [Ondoh, 1991a]

The high latitude limit of the ELF hiss obtained from the ISIS VLF electric field data follows approximately the auroral zone. [Ondoh, 1991b]

Narrow-band hiss occurs typically around 5kHz at invariant latitudes from 56 degrees to 65 degrees. Its peak occurrence rate lies at 58 degrees - 59 degrees for Kp=0-3 and extends over a broader latitude range (56 degrees - 60 degrees) for Kp=4-6. The local time distribution of its occurrence rate has a significant peak at 18-21 MLT for Kp=0-3 and at 0-3 MLT for Kp=4-6. The narrow band 5kHz hiss seems to be generated by cyclotron instability of energetic electrons injected from the magnetotail to the equatorial plasmapause. [Ondoh, 1991c]

Impulsive VLF waves with duration less than 100msec were observed in association with strong narrow band ELF hiss by the DE-1 in low latitudes outside the nighttime plasmapause. Since the impulsive VLF waves occurred even during the spin-modulated intensity minimum of the associated ELF hiss electric field, they seem to be electrostatic whistler mode waves. [Ondoh et al., 1991]

ELF emissions in the frequency ranges above the cyclotron frequencies of helium and oxygen ions were observed by the Akebono satellite in the limited region around the magnetic equator. This phenomenon is interpreted as ion cyclotron mode emissions trapped along the magnetic field lines around the magnetic equatorial plane. Such propagation characteristics can be confirmed by ray tracing including the effects of ions. [Sawada et al., 1991a]

A statistical analysis of propagation characteristics was made for initial observations of Omega signals transmitted from Australia and North Dakota and observed by the Akebono satellite. The magnetospheric region where the Omega signals were frequently observed on board Akebono can be confirmed by ray tracing. Triggered emissions associated with the Australian Omega signal were analyzed. Time evolution of amplitude and phase of the triggered emission were also studied in detail. [Sawada et al., 1991b]

On board the satellite EXOS-D (Akebono), three crossed loop antennas and two pairs of wire antenna can be used to determine the k vector or wave normal direction for VLF waves including ground-based transmitter signals. For example, Omega signals can be detected rather continuously along the satellite trajectories for more than one hour. Spatial variations of the k vector for the Omega signals were studied by using Means' method. The refractive index can also be determined by the observed E and B field. [Yamamoto et al., 1991]

A statistical study was made for ELF emissions especially observed around the geomagnetic equatorial region on board the satellite Akebono in an altitude range from 3,000 km up to 10,000 km (apogee of the satellite). A mechanism based on the ion cyclotron resonant instability due to a temperature anisotropy of hot proton was proposed and was examined by hot plasma ray tracing. [Kasahara et al., 1992]

The different magnetoionic wave modes which accompany the aurora were identified using DE-l not only by their appearance on satellite radio spectrograms, but also by concurrent measurements of their wave polarization and arrival directions, and by ray-tracing models of their expected propagation behavior. [Calvert and Hashimoto, 1990]

Certain Z-mode wave emissions in the earth's magnetosphere are identified using the wave spectra and polarization measurements of the DE-1 Satellite. Hashimoto and Calvert [1990] showed by three-dimensional ray tracing, that these emissions must originate from lower altitudes within the auroral zone and probably from near the plasma frequency inside the auroral plasma cavity.

Tsutsui et al.[1991] examined characteristics of VLF electrostatic noise observed with ISEE 3 in the low-latitude boundary layer of distant geomagnetic tail (~210 Re). The analysis based on a hypothesis identified a wave mode of the observed noise as ion acoustic waves.

Nagano et al. [1992] analyzed intensities of the Australian Omega signal observed by the Akebono satellite in the upper ionosphere over the transmitting station. Using a full wave method to calculate ionospheric propagation of a spherical wave radiated from a ground-based dipole antenna, they calculated field intensities in the upper ionosphere, whose spatial variation was in good agreement with the Akebono observation.

Using a full wave method, Yagitani et al. [1992a] calculated propagation of a spherical wave radiated by a dipole antenna located inside the lower ionosphere. Field intensities in the upper ionosphere and on the ground were calculated and compared with the values observed during Tromso/Akebono campaign. Fairly good agreement was found between the calculated and observed field intensities.

H1.4. LF/MF/HF Wave Phenomena

The first study of the Poynting flux of auroral kilometric radiation were carried out by the PWS onboard the Akebono (EXOS-D) satellite. The initial first result indicated that medium intensity AKR shows L-O mode propagation and there is a case where sudden polarization reversal from the L-O mode to R-X mode associated with the increment of the intensity in the explosive AKR bursts. [Morioka et al., 1990]

Within decametric radio emissions from the region near the galactic center, a pulse component was detected with a period of 421.602 msec, and with a power level that is approximately 0.8% of the background random noise level from the Galaxy. The dispersion effect and the Doppler effect on the observed period suggest that the source of the pulsating component is located at the galactic center. A rotating super massive black hole at the galactic center was inferred as a candidate for the origin of this pulsating component. [Oya et al., 1989]

Oya et al. [1990] presented many fruitful results from the plasma waves and sounder experiments (PWS) onboard the Akebono(EXOS-D) Satellite; i) global distribution and structure of plasmasphere by UHR emissions, ii) data for the generation mechanism and source structure of AKR, iii)discovery of the equatorial enhancement of both the wave turbulence and density turbulence at the magnetic equator, iv) detailed feature of plasma resonance phenomena from sounder experiments.

Generation of the plasma waves by the inverse Landau mechanism of the upper hybrid mode waves and conversion of these plasma waves to the escape mode of the electromagnetic wave proposed as the origin of AKR. The evidences of large fp/fc value (fp/fc > 0.3) and the emissions associated with 2nd harmonics off_UHR discovered by EXOS-D satellite observations support the origin at the upper hybrid mode wave branch and the conversion of that wave into AKR. [Oya, 1990]

The enhancements of the upper hybrid wave emission called equatorialenhancement of the plasma wave turbulence(EPWAT) that are characterized by the increasing level of the upper hybrid emissions were studied on their occurrence regions and occurrence conditions. The results showed EPWAT's encircle the magnetic equator forming a disc region that spreads from 1000km to 10,000km altitude without dependence on the local time. [Oya et al., 1991]

Plasma wave and sounder experiments(PWS) on board the EXOS-D satellite are making effective contribution to study on the energy transfer through the plasmasphere and auroral acceleration region providing data of largely irregular distribution of the electron density, temperature anisotropy and informations on existing free energy of the plasma and the energetic particles. [Oya, 1991]

H1.5. Observational Techniques

The instrument of an automatic direction finding for whistlers was described. [Ohta and Hayakawa, 1992]

A wave distribution function method was proposed to estimate how the wave energy of magnetospheric VLF waves is distributed at the ionospheric base by means of the three field components observed on the ground. [Shimakura and Hayakawa, 1991]

VLF wave instruments on board Akebono were described. With these instruments, wide band VLF spectra, and the wave normal direction of ground based transmitter signals and natural emissions could be successfully observed by using three dimensional loop and search coils and two pairs of wire antennas. [Kimura et al., 1990]

Impedance of wire antennas was measured on board the Akebono satellite by imposing a constant current of VLF frequencies, with an aim to obtain the absolute electric field intensities of VLF waves observed with the antennas. The impedance was obtained in a complex from, i.e., as a resistance and a capacitance. A critical frequency below which the resistive part becomes important was also obtained. [Hashimoto et al., 1991]

A new loop antenna sytem was developed and tested using a sounding rocket S-310-18 to receive waves in VLF and MF ranges. Whistlers, Omega signals, NDT signal and a MF (873kHz) signal were detected in the ionosphere. The ionospheric electron density was estimated from their intensity versus altitude characteristics. [Okada et al., 1990]

Tsutsui et al.[1992] studied radiation properties of magnetic noise from the harness wires of GEOTAIL spacecraft. The results provided an important information on a wiring method to diminish noise radiation from harness wires.

H2. Active Space Experiments and Laboratory Experiments on Plasma Waves

H2.1. Wave Propagation

Sato et al. [1990] reported experimental results on negative ion plasma as well as a brief review of previous experiments. The negative ion plasmas were produced by admitting a small amount of SF6 gas into a single-ended Q-machine plasma. The main interests were focused on the effects of the existence of the negative ions on the characteristics of typical plasma waves and instabilities, i.e., the electron plasma waves, the ion waves, the electrostatic ion cyclotron wave instability, and the drift wave instabilities in negative ion plasmas. The results were consistent with theoretical predictions.

Ishikawa et al. [1990a] performed a numerical analysis on ion wave propagation along a magnetized negative ion plasma column. The analysis showed that there are two branches: a fast and a slow modes, which are concerned mainly with positive and negative ions, respectively. The fast mode is sensitive to the electron density fraction, while the slow mode is not. Measurements were carried out in a negative ion plasma produced by admitting SF6 gas into a Q-machine plasma. A good agreement was found between the analysis and the experimental results on the ion wave propagation.

Negative ion plasmas have new features in plasma physics and its applications, which are to be investigated from both theoretical and experimental points of view. Here recent experiments on negative ion plasmas were presented. [Sato, 1989]

A new method of ion-species and isotope separation was described, which is expected to yield higher mass resolution and collection rate than the conventional ion-cyclotron-resonance technique. [Hatakeyama et al., 1992a]

Spatial cyclotron resonance of an ion beam in a wavy magnetic filed was investigated to realize the separation of stable isotopes. [Mieno et al., 1992a]

Measurements were performed on ion cyclotron oscillations induced by a small emissive electrode floating in a magnetized collisionless plasma column. [Sato et al., 1992a]

Electrostatic ion cyclotron wave is generated when an ion beam is injected along magnetic field lines with multiple mirror configuration under the condition of the beam velocity equal to the product of ion cyclotron frequency and period length of the magnetic field. [Mieno, et al., 1992b]

H2.2. Wave Generation and Instabilities

Simultaneous ground and satellite (Akebono) observations were made on November 28, 1989 for VLF waves generated from the lower ionosphere heated by HIPAS high power HF radio waves amplitude-modulated with a VLF frequency. The 2.5 kHz signal intensity observed on the ground 35 km north-west from the HIPAS site was 1.3 pT, whereas at an altitude of 1,200 km it was 0.25 pT with a wave normal direction nearly along a geomagnetic field line. [Kimura et al., 1991]

The effect of a radial electric field on the potential relaxation instability excited by a positively biased electrode in a single-ended Q-machine was investigated experimentally. [Iizuka and Schrittwieser, 1989]

Iizuka and Schrittwieser [1990] investigated the effect of a radial electric field on the potential relaxation instability (PRI) excited by a positively biased electrode in a single ended Q-machine. It was shown that when the radial electric field in the boundary region between the bulk of the plasma and the thin plasma outside is directed inward, the PRI is suppressed, and a maximum stable axial current flows. However, a radial electric field pointing outward leads to an amplification of the PRI due to the enhancement of the radial ion loss, giving rise to a strong current chopping.

Using two-dimensional electrostatic particle simulation code, Ishiguro et al. [1990] studied the ion cyclotron oscillation driven by applying a positive potential to a small electrode in a magnetized plasma.

In relation to the project of the Space Experiments with Particle Accelerators (SEPAC) reflight using a space shuttle, Ohnuki and Adachi [1992] discussed theoretically the electromagnetic radiation from a density-modulated electron beam antenna of finite length injected along the earth magnetic field into ionosphere.

H2.3. Nonlinear Effects

Matsumoto et al.[1990] described a METS(Microwave Energy Transmission in Space) experiment using the future Space Flyer Unit. Two fundamental areas are addressed: one is the development of a control system for the microwave beam enabling accurate pointing to the energy receiver; the other problem concerns the study of nonlinear propagation effects of the microwave beam as it passes through space plasmas.

Ion beams in a periodic magnetic field were investigated theoretically and experimentally. The spatial cyclotron resonance of ion beams was clearly obtained and detailed features of the phenomenon were commented. [Mieno etal., 1989]

Flute-type fluctuations excited spontaneously at the edge of a strongly magnetized plasma column couple nonlinearly with an externally injected convective cell. [Iizuka et al, 1989a]

The behavior of lithium ion beams in a periodic wavy magnetic field was investigated experimentally to prove the spatial cyclotron resonance of selected isotopes. [Mieno et al., 1991]

Large-scale plasma motions across a magnetic field were observed in the vicinity of an antenna which inductively generates axisymetric radio-frequency fields. [Hatakeyama et al., 1992b]

A plasma potential formation was experimentally investigated in a collisionless magnetized plasma flow in the presence of localized radio-frequency electric fields. [Sato et al., 1992b]

H2.4. Particle Acceleration, Heating and Diffusion

The electron energy distribution was controlled in a weakly magnetized low pressure dc discharge plasma by using pins installed in a hollow cathode. The electron temperature was controlled continuously from 0.3eV to 3eV. [Iizuka et al., 1989b]

A radial potential profile was successfully changed from hill- to well-shaped by biasing segmented endplates in a strongly magnetized plasma produced by the electron cyclotron resonance. [Tsushima and Sato, 1991]

Plasma parameters are measure in a low-pressure discharge plasma produced by the 2.45-GHz electron cyclotron resonance. Radial plasma profiles which are important for homogeneous plasma processings were found to be very sensitive to the resonance position in a plasma production chamber. [Iizuka and Sato, 1991]

Temporal and spatial evolutions of plasma potential formation were experimentally investigated in an ECR plasma terminated by biased segmented endplates under a mirror configuration of magnetic field. [Nomura et al., 1991]

H3. Theory and Computer Experiments on Plasma Waves

H3.1. Wave Propagation

Whistler-mode propagation in a magneto-plasma was studied in terms of both ray and full-wave theories, and the importance of the critical frequency in ray focusing was investigated in details. [Ishikawa et al., 1990b]

The ray-tracing studies yielded that the inner edge of the plasmapause is a very effective waveguide for low frequency (Lambda_0(frequency normalized by gyrofrequency) < 0.4) waves by means of the gradient trapping, and also that the outer edge acts as a guide for higher frequency (Lambda_0 > 0.5) waves. [Hattori et al., 1991d]

A combination of the observed wave normals of chorus in the off-equator with the ray-tracing yielded that chorus is generated with small wave normal angle at the equator, followed by the non-ducted propagation. [Hattori et al., 1990]

Yagitani et al. [1992b] performed particle simulation of wave propagation parallel to an external magnetic field in a nonuniform plasma, and compared simulation results with full wave solutions. Under the same plasma condition the simulation reproduced same wave propagation as the full wave solution. Increasing plasma temperature and amplitude of the electromagnetic wave, they showed quantitatively how plasma kinetics and nonlinearity, which are not examined by the conventional full wave method, alter the wave propagation.

H3.2. Wave Generation and Instabilities

Higuchi [1990] applied the transformation approximation for the plasma dispersion function to an electromagnetic ion-cyclotron instability caused by proton temperature anisotropy. It was shown that the transformation approximation method yields an unreliable estimate of the growth rate for values greater than a critical thermal anisotropy. Cold-heavy-ion effects on the ion-cyclotron instability were also investigated.

The stability of stationary Langmuir turbulence against a test high-frequency electromagnetic perturbation was studied. The enhanced growth of the electromagnetic radiation through the new mode coupling process is obtainedfor an open system plasma with a particle source and sink. The growth rate of the electromagnetic mode comes from the direct mode coupling terms for unmagnetized plasma. [Nambu et al., 1990]

The emission of extraordinary mode radiation in a plasma with Langmuir turbulence driven by an electron beam was considered. The energy necessary for the growth of the extraordinary mode was derived from the Langmuir turbulence. The scope of application of the results to space-plasma observation was stressed. [Sarma et al., 1991a]

A theory of emission of electromagnetic radiation in a plasma with Langmuir turbulence through the plasma-maser interaction owing to a dissipative nonlinear force was presented. The nonlinear force that arises as a result of the resonant interaction between electrons and modulated fields was shown to drive the instability. [Sarma et al., 1991b]

Kaya et al.[1989] performed test particle simulations to study nonlinear interactions of water group ions with large amplitude whistler wave packets detected at the leading edge of steepened magnetosonic waves observed near Giacobini-Zinner, The nonlinear trapping motion in the wave structure leads to the effective energy transfer from the water group ions to the whistler wave packets in the leading edge of the steepened MHD waves.

Kojima et al. [1989] studied the nonlinear evolution of beam generated RH waves by one-dimensional hybrid computer experiments. Both wave-particle and subsequent wave-wave interactions were examined. The RH waves grow through the interaction with an ion beam formed by pick-up heavy ions near comets. The excited waves saturates by wave-wave interactions via the decay instability.

Omura and Matsumoto[1989] presented a brief review on previous works and our results of particle simulations on nonlinear behavior of large amplitude circularly polarized electromagnetic cyclotron waves propagating parallel to B_0. Beam instability causes finite amplitude whistler and R-mode Alfven waves. Whistler waves show a smooth inverse cascading process via a modulational instability, while R-mode Alfven waves show a discrete inverse cascading process via decay instability.

To study the nonlinear plasma dynamics associated with electrodynamic tether system, Usui et al.[1991] performed a two dimensional computer experiments using an electromagnetic particle code. Plasma response to the tether system, the electron beam dynamics, and the LHR wave emission were investigated.

The modulational instability of finite-amplitude, longitudinal, nonlinear plasma oscillations in a cold plasma was discussed. Stable and unstable regimes appear alternatively as the wave nonlinear parameter epsilon varies. A possible laboratory experiment that may confirm this result was suggested. [Hada et al., 1992]

Tsurutani et al. [1989] examined the physical characteristics of high frequency wave packets which are detected at the steepened edge of magnetosonic waves near comet Giacobini-Zinner. The high frequency wave packets are observed to be attached to the long period magnetosonic waves. They propagate upstream and are blown back by the solar wind. The properties of the wave packets are consistent with anomalously Doppler shifted right-hand polarized waves.

H3.3. Nonlinear Effects

The temporal dynamics of the fast reconnection mechanism was systematically studied. It was found that the reconnection process is strongly controlled by the resistivity model. Only when the resistivity is locally enhanced self-consistently with the global reconnection flow, the fast reconnection mechanism, involving switch-off shocks, can rapidly build up and be sustained steadily. [Ugai, 1992]

The evolution of an initial current sheet system was studied in three dimensions, where fast reconnection spontaneously develops in a finite region of the current sheet. It was found that a magnetic shear (rotation) is caused along the plasmoid boundary (due to intermediate waves), which gives rise to a field-aligned current. The fast reconnection development in three dimensions causes a drastic change in the overall current system. [Ugai, 1991a]

Computer simulations study the basic three-dimensional structure of the fast reconnection mechanism. It was shown that if three-dimensional effects are not so strong, the fast reconnection mechanism, involving three-dimensional standing switch-off shocks, can eventually be set up. In the middle of the system, the resulting structure is quite similar to the well-known (two-dimensional) quasi-steady fast reconnection mechanism. [Ugai, 1991b]

A model equation for the ionization wave (Duffing's equation) was studied. The system shows chaotic behavior via an intermittent route to chaos. It is left for experimentalists to devise experiments to test the theoretical predictions. [Nambu and Kawabe, 1990]

A new enhanced radiation process from plasma turbulence (plasma-maser) was interpreted as "dissipative structure" in plasma turbulence. The plasma-maser process is effective in an open plasma system where some of the input energy is dissipated as anomalous radiation. The ordinary mode growth rate in the presence of the enhanced stationary Langmuir turbulence is obtained and the results have potential importance to clarify the mechanism of the anomalous radiation in plasma astrophysics. [Nambu et al., 1991]

The plasma maser, an interesting nonlinear process in plasma, is an effective means of energy up-conversion in frequency from Langmuir turbulence to the electrostatic Bernstein mode. It was shown here that the primary momentum and energy source of the plasma maser is the external magnetic field, which is not the case for the standard mode coupling processes. For strongly magnetized plasma, the growth rate of the Bernstein mode arises from the polarization term. These results have potential importance in the interpretation of anomalous radiation phenomena in astrophysical, laboratory, strongly magnetized plasma, the growth rate of the Bernstein mode arises from and fusion plasmas. [Nambu et al., 1992]

Omura et al. [1991] reviewed theoretical and numerical studies of VLF triggered emissions generated by man-made signals propagating in the whistler mode in the magnetosphere. The main purpose of the paper is to clarify what problems remain unresolved and to make suggestions for future studies.

Usui et al. [1993] studied plasma responses to a high potential satellite in the electrodynamic tether system with the aid of two-dimensional electromagnetic particle computer experiments. The transient process of the plasma response to the satellite and the spatial profiles of plasma density and of plasma current were examined. The current-voltage characteristics of the satellite in the steady state were also examined by comparing to the classical theories.

Alfven waves play essential roles in various space plasma environment. With emphasis on introducing relevant articles to interested readers outside of the field, several important nonlinear aspects of Alfven waves were briefly surveyed. In particular, mathematical and physical properties of the derivative nonlinear Schroedinger equation (DNLS) that models the evolution of quasi-parallel Alfven waves were discussed. [Hada, 1993]

The chaos in a one dimensional Alfven system was discussed. The evolution equations were numerically integrated using the DNLS equation. For the Hamiltonian case, the solutions near the soliton separatrices become chaotic as amplitude of the external driver increases, while the dissipative system exhibits a wealth of dynamical behavior, typical route of the regular to chaos transition. [Hada et al., 1992]

Intermediate shocks were studied in a two-fluid model that includes finiteion inertia dispersion and in a hybrid model in which the full ion dynamics is retained while the electrons are treated as a massless fluid. It was shown that in both models intermediate shocks can be formed through wave steepening, meaning that they are stable and possess shock structures. [Wu and Hada, 1991a]

Rotational discontinuities were studied in a two-fluid model that includes finite ion inertia dispersion and in a hybrid model in which the full ion dynamics is retained while the electrons are treated as a massless fluid. It was shown that as in previous dissipative MHD studies, a rotational discontinuity is unstable in both models and evolves to a 2 to 3 intermediate shock, a slow rarefaction wave, and other waves. [Wu and Hada, 1991b]

The stability of finite-amplitude weakly dispersive circularly polarized MHD wave trains with respect to oblique modulations was investigated. The mathematical model was a multi-dimensional extension of the DNLS equation. It was found that the right-hand polarized wave, which is stable with respect to parallel modulations, is unstable with respect to certain oblique modulations for most primary wavenumbers. [Mjolhus et al., 1990]

Injection of electrons from a floating electrode into a plasma and related potential formation were studied by means of a particle simulation. [Ishiguro and Sato, 1989]

H3.4. Particle Acceleration, Heating and Diffusion

Ishiguro and Sato [1991] investigated a potential formation due to contact between a floated emissive electrode and collisionless plasma by means of particle simulations. When low-temperature high-density thermal electrons are emitted, a negative potential dip is created in front of the electrode. With an increase in the emission flux from the electrode, the electrode potential increases and finally becomes larger than the plasma potential.

Hatakeyama et al. [1991] investigated the plasma particle drifts due to traveling waves having the cyclotron frequencies by using a particle orbit theory. The results showed that the traveling waves give rise to the charged particle drifts perpendicular both to the wave propagation and the external magnetic field lines. These results are applicable to particle flux control of magnetized plasmas.

H3.5. Techniques of Data Analysis and Computer Experiments

As a lecture given at the 4th ISSS in Kyoto (1992), Tanaka [1993a] presented an easy-to-understand introduction to the realm of implicit particle simulations. A FORTRAN source of the core part of the program is provided. An interested reader is recommended to refer to the above paper which shows full description of the method.

A new simulation method for kinetic-MHD plasmas was described. Though the method adopts particle ions, electrons and Maxwell's equations, it enables us large time-and-space scale simulations via implicit treatment of particle and field equations. The method properly reproduces not only shear, kinetic Alfven and magnetosonic waves, but it can also simulate instabilities of Alfven-ion-cyclotron waves and helical kink mode in three-dimensions. [Tanaka, 1993b]

Tanaka [1991] presented an introductory textbook to plasma physics written in Japanese. This is not only a standard textbook which includes ABC's of plasma physics, kinetic and MHD theories of waves and instabilities, and nonlinear processes, but it also deals with an advanced, state-of-the-art world of various particle simulations.


Calvert, W., and K. Hashimoto, The magnetoionic modes and propagation properties of auroral radio emissions, J. Geophys. Res., 95, A4, 3943 (1990)

Hada, T., and M. Nambu, On stability of strongly nonlinear plasma oscillations, Phys. Fluids B, 4, 757 (1992)

Hada, T., C. F. Kennel, B. Buti, and E. Mjolhus, Chaos in driven Alfven systems, Research Trends in Physics, Nonlinear and Relativistic Effects in Plasmas, 537, xvi+764 (1992)

Hada, T., Nonlinear evolution of Alfven waves in space plasmas, in Nonlinear Processes in Physics, Ed. A. S. Fokas, D. J. Kaup, A. C. Newell, V. E. Zakharov, Springer-Verlag, 169 (1993)

Hashimoto, K., and W. Calvert, Observations of the Z mode with DE 1 and its analysis by three-dimensional ray tracing, J. Geophys. Res., 95, A4, 3933 (1990)

Hashimoto, K., I. Nagano, T, Okada, M. Yamamoto, and I. Kimura, Antenna vector impedance measurement by the EXOS-D (Akebono) very low frequency plasma wave instrument (VLF), Geophys. Res. Lett., 18, 2, 313 (1991)

Hatakeyama, R., N. Y. Sato, and N. Sato, Plasma particle drifts due to traveling waves with cyclotron frequencies, J. Phys. Soc. Jpn., 60, 2815 (1991)

Hatakeyama, R., N. Y. Sato, and N. Sato, An efficient mass separation by using traveling waves with ion cyclotron frequencies, Nucl. Instrum. Metho. Phys. Res. B, 70, 21 (1992)

Hatakeyama, R., S. Miyanuki, N. Y. Sato, and N. Sato, Inward and outward plasma motion induced by axisymetric electromagnetic fields around the ion cyclotron frequency, Proc. Int. Conf. Plasma Phys., 3, 1709 (1992)

Hattori, K., and M. Hayakawa, A Study of the periodicity in occurrence of natural magnetospheric chorus emissions, Res. Lett. Atmosph. Electr., 9, 109 (1989)

Hattori, K., K. Ishikawa, and M. Hayakawa, Ray tracing interpretation of wave normal directions of chorus emissions observed in the off-equatorial region of the outer magnetosphere, Proc. NIPR Symp. on Upper Atmos. Phys., 3, 70 (1990)

Hattori, K., M. Hayakawa, D. Lagoutte, M. Parrot, and F. Lefeuvre, An experimental study of the role of hiss in the generation of chorus in the outer magnetosphere, as based on spectral analysis and direction finding measurements onboard GEOS1, Proc. NIPR Symp. on Upper Atmos. Phys., 4, 20 (1991)

Hattori, K., M. Hayakawa, D. Lagoutte, F. Lefeuvre and M.Parrot, On the experimental results of hiss-triggered chorus observed onboard GEOS-1 satellite in the outer magnetosphere, in Environmental and Space Electromagnetics, Ed. H. Kikuchi, Springer-Verlag, 258 (1991)

Hattori, K., M. Hayakawa, D. Lagoutte, M. Parrot and F. Lefeuvre, Further evidence of triggering chorus emissions from wavelets in the hiss band, Planet. Space Sci., 39, 1465 (1991)

Hattori, K., K. Ishikawa and M. Hayakawa, Ray-tracing study of the plasmapause effect on non-ducted whistler-mode wave propagation, Planet. Space Sci., 39, 425 (1991)

Hayakawa, M., Satellite observation of equatorial VLF radio noises and their association with lightnings, J. Geomag. Geoelectr., 41, 573 (1989)

Hayakawa, M., F. Lefeuvre, and J. L. Rauch, On the system of Aureol-3 satellite direction finding for ionospheric and magnetospheric ELF waves, Trans. Inst. Elect. Inform. Comm. Engrs. Japan, E73, 942 (1990)

Hayakawa, M., Observation at moshiri (L=1.6) of whistler-triggered VLF emissions in the electron slot and inner radiation belt regions, J. Geomag. Geoelectr., 43, 267 (1991)

Hayakawa, M., Direction finding of magnetospheric VLF/ELF emissions and their generation mechanism, in Environmental and Space Electromagnetics, Ed. H. Kikuchi, Springer-Verlag, 155 (1991)

Hayakawa, M., K. Hattori, S. Shimakura, M. Parrot and F. Lefeuvre, Direction finding of chorus emissions in the outer magnetosphere and their generation and propagation, Planet. Space Sci., 38, 135 (1991)

Hayakawa, M., K. Ohta, and S. Shimakura, Direction finding of very-low-latitude whistlers and their propagation, in Environmental and Space Electromagnetics, Ed. H. Kikuchi, Springer-Verlag, 168 (1991)

Hayakawa, M., and K. Ohta, The propagation of low-latitude whistlers: a review, Planet. Space Sci., 40, 1339 (1992)

Hayakawa, M., and K. Ohta, On the L-dependence of whistler triggered emissions as based on the measurement at Ceduna, Australia (L=1.93), Planet. Space. Sci., 40, 1193 (1992)

Hayakawa, M., and S. S. Sazhin, Mid-latitude and plasmaspheric hiss: a review, Planet. Space Sci., 40, 1325 (1992)

Hayakawa, M., S. Shimakura, Y. Kobayashi, and N. Sato, Statistical characteristics of the polarization of Pc 1 micropulsations at high latitudes, Planet. Space Sci., 40, 1353 (1992)

Hayakawa, M., S. Shimakura, T. Kobayashi, and N. Sato [1992], A study of polarization of IPDP pulsations and their generation mechanism, Planet. Space Sci., 40, 1081 (1992)

Higuchi, Y., Transformation approximation method for an electromagnetic ion-cyclotron instability caused by proton temperature anisotropy, J. Plasma Phys., 44, pt.3, 467 (1990)

Iizuka, S., and R. Schrittwieser, The influence of radial electric field on the potential relaxation instability, Proc. Int. Conf. Plasma Phys., 3, 1117 (1989)

Iizuka, S., T. Huld, H. L. Pecseli, and J. J. Rasmussen, Forced organization of flute-type fluctuations by convective cell injection, Plasma Phys. Contr. Fus., 31, 855 (1989)

Iizuka, S., T. Koizumi, and N. Sato, Control of electron energy distribution in a discharge plasma, Proc. Int. Conf. Plasma Phys., 3, 1193 (1989)

Iizuka, S., and R. Schrittwieser, Quenching and amplification of the potential relaxation instability by control of the radial electric field, Physical Lett. A, 149, 7, 8, 393 (1990)

Iizuka, S., and N. Sato, Plasma structures in an electron cyclotron resonance plasma processing device, J. Appl. Phys., 70, 4165 (1991)

Ishiguro, S., and N. Sato, Injection of electrons from a floating electrode into a plasma and potential formation, Proc. Int. Conf. Plasma Phys., 3, 1117 (1989)

Ishiguro, S., K. Nakagawa, and N. Sato, Numerical simulation of potential-driven ion cyclotron oscillation, Proc. Int. Toki Conf. Plasma Phys. and Contr. Nucl. Fus., 2, 158 (1990)

Ishiguro, S., and N. Sato, Potential formation due to contact between floated emissive electrode and plasma, J. Phys. Soc. Japan, 60, 7, 2218 (1991)

Ishikawa I., C. Yoshida, S. Iizuka, and N. Sato, Ion waves in a negative ion plasma, Sci. Papers I.P.C.R., 85, 42 (Available from The Institute of Physical and Chemical Research, Wako-shi, Saitama, 351-01 Japan) (1990)

Ishikawa, K., K. Hattori, and M. Hayakawa, A study of ray focusing of whistler-mode waves in the outer magnetosphere, Trans. Inst. Elect. Inform. Comm. Engrs. Japan, E73, 149 (1990)

Kasahara, Y., A. Sawada, M. Yamamoto, I. Kimura, K. Hayashi, and S. Kokubun, Ion cyclotron emissions observed by the satellite Akebono in the vicinity of the magnetic equator, Radio Sci., 27, 347 (1992)

Kaya, N., H. Matsumoto, and B. T. Tsurutani, Test particle simulation study of whistler wave packets observed near comet Giacobini-Zinner, Geophys. Res. Lett., 16, 25 (1989)

Kimura, I., K. Hashimoto, I. Nagano, T. Okada, M. Yamamoto, T. Yoshino, H. Matsumoto, M. Ejiri, and K. Hayashi, VLF observations by the Akebono (EXOS-D) satellite, J. Geomag. Geoelectr., 42, 459 (1990)

Kimura, I., A. Wong, B. Chouinard, T. Okada, M. Mccarrick, I. Nagano, K. Hashimoto, R. Wuerker, M. Yamamoto and K. Ishida, Satellite and ground observations of HIPAS VLF modulation, Geophys. Res. Lett., 18, 309 (1991)

Kohata, H., I. Kimura, N. Wakai, and T. Ogawa, Correlation of nighttime MF signal strength with solar activity, J. Geomag. Geoelectr.42, 825 (1990)

Kojima, H., H. Matsumoto, Y. Omura, and B. T. Tsurutani, Nonlinear evolution of high frequency R-mode waves excited by water group ions near comets: computer experiment, Geophys. Res. Lett., 16, 9 (1989)

Matsumoto, H., N. Kaya, and M. Nagatomo, Microwave energy transmission experiment, Space Power., 9, 113 (1990)

Mieno, T., R. Hatakeyama, and N. Sato, Spatial cyclotron resonance of ion beams, J. Adv. Sci., 1, 31 (1989)

Mieno, T., E. Matsumoto, K. Yamagiwa, and N. Sato, Spatial cyclotron resonance of lithium ion beams, J. Adv. Sci., 3, 135 (1991)

Mieno, T., E. Matsumoto, K. Yamagiwa, and N. Sato, Ion mass separation by use of spatial cyclotron resonance, Nucl. Instrum. Metho. Phys. Res. B, 70, 33 (1992)

Mieno, T., R. Hatakeyama, and N. Sato, Generation of ion cyclotron wave in an ion beam by a periodic magnetic field, Proc. Int. Conf. Plasma Phys., 3, 1919 (1992)

Mjolhus, E., and T. Hada, Oblique stability of circularly polarized MHD waves, J. Plasma Phys., 43, 257 (1990)

Morioka, A., H. Oya, and K. Kobayashi, Polarization and mode identification of auroral kilometric radiation by PWS system onboard the Akebono (EXOS-D) satellite, J. Geomag. Geoelectr., 42, 443 (1990)

Nagano, I., P. A. Rosen, S. Yagitani, K. Miyamura, M. Hata, I. Kimura, K. Hashimoto, and T. Okada, Intensity of the Australian Omega signal observed by the Akebono satellite: comparison with a full wave calculation, Proceedings of ISAP'92, SAPPORO, Japan, 189 (1992)

Nambu, M., and T. Kawabe, A possible plasma wave chaos Phys. Fluids B, 2, 11, 2545 (1990)

Nambu, M., S. N. Sarma, and K. K. Sarma, Anomalous radiation from a langmuir turbulence, Phys. Fluids B, 2, 2, 302 (1990)

Nambu, M., T. Hada, S. N. Sarma, and S. Bujarbarua, Dissipative structure in plasma turbulence, J. Phys. Soc. Japan, 60, 9, 3004 (1991)

Nambu, M., S. N. Sarma, and K. K. Sarma, Momentum source of plasma maser, Phys. Rev. A, 45, 7456 (1992)

Nomura, F., A. Tsushima, and N. Sato, Evolutions of plasma potential controlled by biased segmented endplates, J. Phys. Soc. Jpn., 60, 3706 (1991)

Ohnuki, S. and S. Adachi, Electromagnetic wave radiation in lower hybrid frequency range from modulated charge particle beams in space, Trends in Plasma Science, vol.1, Trivandrum, India, Research Trends, 119 (1992)

Ohta, K., M. Hayakawa, K. Baba, and H. Eguchi, Frequency dependence of the direction of arrival of low-latitude whistlers, Res. Lett. Atmosph. Electr., 9, 43 (1989)

Ohta, K., and M. Hayakawa, The correlation of whistler occurrence rate at a low latitude with thunderstorm activity at its conjugated region and with solar activity, Pure Appl. Geophys., 133, 167 (1990)

Ohta, K., M. Hayakawa, and S. Shimakura, Frequency dependence of ionospheric exit points and polarization of daytime whistlers at low latitude, in Environmental and Space Electromagnetics, Ed. H. Kikuchi, Springer-Verlag, 172 (1991)

Ohta, K., and M. Hayakawa, An automatic whistler direction finder, Geomagn. and Aeronomy, 32, 34 (in Russian) (1992)

Okada, T. and I. Nagano, Rocket experiment of VLF and MF radio wave measurement by using a single loop antenna, Trans. IEICE, E73, 237 (1990)

Omura, Y., and H. Matsumoto, Particle simulations of nonlinear whistler and Alfven wave instabilities: amplitude modulation, decay, soliton, and inverse cascading, Plasma waves and instabilities at comets and in magnetospheres Ed. B. T. Tsurutani, and H. Oya, 51 (1989)

Omura, Y., D. Nunn, H. Matsumoto and M. J. Rycroft, A review of observation, theoretical and numerical studies of VLF triggered emissions, JATP, 53, 351 (1991)

Ondoh, T., Broad-band auroral VLF hiss and inverted-V electron precipitation in the polar magnetosphere, J. Atmos. Terr. Phys., 52, 5, 385 (1990)

Ondoh, T., Polar hiss observed by ISIS satellites, in Magnetospheric Substorms, Geophysical Monograph, American Geophysical Union, 387 (1991a)

Ondoh, T., Polar VLF emissions observed by ISIS satellites, Ed. H. Kikuchi, Environmental and Space Electromagnetics, Springer-Verlag, Tokyo, 139 (1991b)

Ondoh, T., Characteristics of narrow band mid-latitude hiss observed in the topside ionosphere, J. Communications Res. Lab., 387, 2, 319 (1991c)

Ondoh, T., Y. Nakamura, and S. Watanabe, Impulsive plasma waves observed by DE-1 in the magnetosphere, Advances in Space Research, 11, 41 (1991)

Oya, H., M. Iizima, and A. Morioka, Possible detection of a pulsar of decametric radio waves in the direction of the galactic center, J. Geomag. Geoelectr., 41, 331 (1989)

Oya, H., Origin of auroral kilometric radiation as conversion of the upper hybrid mode plasma waves, Proc. Japan Acad., 66 Ser. B, 129 (1990)

Oya, H., A. Morioka, K. Kobayashi, M. Iizima, T. Ono, H. Miyaoka, T. Okada, and T. Obara, Plasma wave observation and sounder experiment (PWS) using the Akebono (EXOS-D) satellite - instrumentation and initial results including discovery of the high altitude equatorial plasma turbulence, J. Geomag. Geoelectr., 42, 411 (1990)

Oya, H. Studies on plasma waves in the plasmasphere and auroral particle acceleration region by PWS on board the EXOS-D (Akebono) satellite, J. Geomag. Geoelectr., 43, 369 (1991)

Oya, H., M. Iizima, and A. Morioka, Plasma turbulence disc circulating the equatorial region of the plasmasphere identified by the plasma wave detector (PWS) onboard the Akebono (EXOS-D) satellite, Geophys. Res. Lett., 18, 329 (1991)

Sarma, S. N., K. K. Sarma, and M. Nambu, Plasma maser theory of the extraordinary mode in the presence of Langmuir turbulence, J. Plasma Phys., 46, 2, 331 (1991)

Sarma, K. K., S. N. Sarma, M. Nambu, and T. Hada Electromagnetic emission due to nonlinear forces, Phys. Rev. A, 43, 5, 5555 (1991)

Sato, N., Negative ion plasma, Proc. Int. Conf. Plasma Phys., 79, (1989)

Sato, N., I. Ishikawa, C. Yoshida, S. Iizuka, and R. Hatakeyama, Electrostatic waves in negative ion plasmas, Sci. Papers I.P.C.R., 85, 33 (Available from The Institute of Physical and Chemical Research, Wako-shi, Saitama, 351-01 Japan) (1990)

Sato, N., R. Hatakeyama, K. Aoyama, and W. X. Ding, Ion cyclotron oscillations induced by an emissive electrode floating in a magnetized collisionless plasma column, Proc. Int. Conf. Plasma Phys., 3, 1765 (1992)

Sato, N. Y., R. Hatakeyama, and N. Sato, Plasma potential formation in the presence of localized radio-frequency electric field, Proc. Int. Conf. Plasma Phys., 3, 1705 (1992)

Sawada, A., Y. Kasahara, M. Yamamoto, I. Kimura, S. Kokubun and K. Hayashi, ELF emissions observed by the EXOS-D satellite around the geomagnetic equatorial region, Geophys. Res. Lett., 18, 317 (1991)

Sawada, A., Y. Kishi, M. Yamamoto, A. Sakurai, Y. Kasahara, and I. Kimura, Propagation characteristics of Omega signals and their triggered emissions observed by EXOS-D satellite, Geophys. Res. Lett., 18, 321 (1991)

Sazhin, S. S., and M. Hayakawa, Magnetospheric chorus emissions: a review, Planet. Space Sci., 40, 681 (1992)

Sazhin, S. S., M. Hayakawa, and K. Bullough, Whistler diagnostics of magnetospheric parameters: a review, Ann. Geophysicae, 10, 293 (1992)

Shimakura, S., and M. Hayakawa, On the Estimation of the ionospheric exit regions of magnetospheric VLF radio waves by the use of wave energy distribution in wave number Space, Springer-Verlag, 299 (1991)

Shimakura, S., T. Yamamoto, and M. Hayakawa, On the short and long periodicities in whistler occurrence rate and their implication, Res. Lett. Atmosph. Electr., 1, 23 (1991)

Tanaka, M., Physics of high-temperature plasmas, pp.1-304, Maruzen Pub. Co. (in Japanese) (1991)

Tanaka, M., 3-D macroscale electromagnetic particle simulation method for large space-scale, low-frequency plasma phenomena, Lectures in the 4-th International School of Space Science, Ed. H. Matsumoto and Y. Omura, Terra Sci. Pub. (1993a)

Tanaka, M., A simulation of low-frequency electromagnetic phenomena in kinetic plasmas of three dimensions, J. Comput. Phys., 105 (1993b)

Tsuji, S., M. Hayakawa, S. Shimakura, and K. Hattori, On the statistical properties of magnetospheric ELF/VLF hiss, Proc. Natl Inst. Polar Res., Symp. on Upper Atmos. Phys., 2, 74 (1989)

Tsurutani, B. T., E. J. Smith, A. L. Brinca, R. M. Thorne, and H. Matsumoto, Properties of whistler mode wave packets at the leading edge of steepened magnetosonic waves. comet Giacobini-Zinner, Planet. Space Sci., 37, 167 (1989)

Tsushima, A., and N. Sato, Control of radial potential profile by biased segmented endplates in an ECR plasma, J. Phys. Soc. Jpn., 60, 2665 (1991)

Tsutsui, M., R. J. Strangeway, B. T. Tsurutani, H. Matsumoto, J. L. Phillips, and M. Ashour-Abdalla [1991], Wave mode identification of electrostatic noise observed with ISEE 3 in the deep tail boundary layer, J. Geophys. Res., 96, 14065 (1991)

Tsutsui, M., H. Kojima, I. Nagano, H. Sato, T. Okada, H. Matsumoto, T. Mukai, and M. Kawaguchi, Magnetic radiations from harness wires of spacecraft, IEICE Trans. Commun., E75-B, No.3, 174 (1992)

Ugai, M., Computer simulations of field-aligned currents generated by fast magnetic reconnection in three dimensions, J. Geophys. Res., 96, A12, 21173 (1991a)

Ugai, M., Computer modeling of three-dimensional dynamics of fast reconnection, J. Plasma Phys., 45, 2, 251 (1991b)

Ugai, M., Computer studies on development of the fast reconnection mechanism for different resistivity models, Phys. Fluids B, 4, 2953 (1992)

Usui, H., H. Matsumoto, and Y. Omura [1991], Electron beam injection and associated LHR wave excitation: computer experiments of (SHUTTLE) electrodynamic tether system, J. Geophys. Res., 18, 821 (1991)

Usui, H., H. Matsumoto, and Y. Omura, Plasma response to high potential satellite in electrodynamic tether system, J. Geophys. Res., 98, 1531 (1993)

Wu, C. C., and T. Hada, Formation of intermediate shocks in both two-fluid and hybrid models, J. Geophys. Res., 96, no.A3, 3769 (1991a).

Wu, C. C., and T. Hada, On rotational discontinuities in both two-fluid and hybrid models, J. Geophys. Res., 96, no.A3, 3755 (1991b).

Yagitani, S., K. Miyamura, I. Nagano, and I. Kimura, Full wave calculation of ELF/VLF wave fields radiated from a dipole antenna in the ionosphere, Proceedings of ISAP'92, SAPPORO, Japan, 185 (1992a)

Yagitani, S., I. Nagano, Y. Omura, and H. Matsumoto, Comparison between particle simulation and full wave analysis for wave propagation in a nonuniform plasma, Radio Sci., 27, 4, 449 (1992b)

Yamamoto, M., Y. Ito, Y. Kishi, A. Sawada, I. Kimura, I. Nagano, E. Kennai, T. Okada, and K. Hashimoto, k vector measurements of VLF signals by the satellite EXOS-D, Geophys. Res. Lett., 18, 325 (1991)

Yoshino, T., On the distribution of polar electrostatic emissions and their relationships to auroral hiss and direction finding measurements of saucer emission in polar regions observed by ISIS, Kyokko and Akebono satellites, Adv. Space Res., 11, 45 (1991)

Zhang, X-J., X-Q. Ruan, T. Sato, I. Kimura, S. Fukao, and S. Kato Profiles of electron density in the lower ionosphere observed by the MU radar, J. Geomag. Geoelectr., 43, 179 (1991)

(I. Nagano)