A5040519961- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Astro and Planetary Science
- Dust and Plasma Wave Phenomena
- Planetary Science and Exploration
- Geomagnetism and Paleomagnetism Studies
- Magnetic confinement fusion research
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Earthquake Detection and Analysis
- Laser-induced spectroscopy and plasma
- Laser-Matter Interactions and Applications
- High-pressure geophysics and materials
- Particle accelerators and beam dynamics
- Advanced Fiber Laser Technologies
- Nonlinear Waves and Solitons
- Geophysics and Gravity Measurements
- Spacecraft and Cryogenic Technologies
- Nonlinear Photonic Systems
- Gyrotron and Vacuum Electronics Research
- Quantum optics and atomic interactions
- Seismic Waves and Analysis
- Stellar, planetary, and galactic studies
- Fluid Dynamics and Turbulent Flows
- Radio Wave Propagation Studies
Max Planck Institute for Solar System Research
2005-2024
University of Science and Technology of China
2020-2022
University of Alberta
2007-2016
Max Planck Society
1999-2014
Max Planck Institute for Astronomy
1997-2014
International Space Science Institute
1998-2014
Leibniz Institute for Crystal Growth
2011
Universität Greifswald
2010
University of KwaZulu-Natal
2003
Max Planck Institute for Extraterrestrial Physics
1994-1997
Abstract. The plasma-wave experiment ASPI (analysis of spectra plasma waves and instabilities) on board the INTERBALL spacecraft is a combined wave diagnostics experiment. It performs measurements DC AC magnetic field vector by flux-gate search-coil sensors, electric Langmuir double probes current split probe. Preliminary data analysis shows low noise levels sensors compatibility new with results previous missions. During several months in-orbit operation rich collection was acquired,...
Parker Solar Probe (Parker) is capable of making observations type III radio bursts in their generation region. PSP recorded a burst with frequency decay down to the local Langmuir and simultaneously slow electrostatic plasma waves near frequency, which often harmonics. From electric field fluctuations, k-value wave estimated be 0.14 kλd = 0.4 phase velocity was
Abstract. The interaction of the solar wind with ionosphere planet Mars is studied using a three-dimensional hybrid model. has only weak intrinsic magnetic field, and consequently its directly affected by wind. gyroradii protons are in range several hundred kilometers therefore comparable characteristic scales region. Different boundaries emerge from continuously produced ionospheric heavy-ion plasma, which could be identified as bow shock (BS), ion composition boundary (ICB) pile up (MPB),...
Data obtained with the MAGMA magnetometer on subsolar passes of Phobos spacecraft during its 3 elliptic orbits reveals a turbulent bow shock strong foot consistent reflection solar wind protons. The lies at distance 1.47 ± .03 R M . circular orbit phase mission highly varying location. median terminator crossing 2.72 Mars radii. location in plane is sensitive to neither EUV flux nor planetary longitude.
Large‐amplitude ultralow‐frequency wave structures observed on both sides of the magnetic pileup boundary comet P/Halley during flyby Giotto spacecraft have been analyzed using suprathermal electron density and field observations. Upstream boundary, magnitude variations are anticorrelated, while in region these quantities clearly correlated. Both front behind waves quasi‐perpendicular as a minimum variance analysis shows. A detailed comparison our observations prepileup with theoretical...
We analyze the nonlinear evolution of differential streaming between core protons and alpha particles (or any secondary minor protons) based on analysis fully multifluid MHD equations. It is shown that such an ion beam‐plasma system possesses equilibrium state with a remnant streaming. The properties this are studied. through action hydromagnetic waves can attain which characterized by “gyrating” motion both populations phase shift π. bring about transition either Alfven or magnetosonic...
The Martian environment is characterized by the presence of heavy (oxygen) ions planetary origin which strongly influence solar wind dynamics, including bow shock structure and position may cause additional plasma boundaries in magnetosheath. In this paper dispersion characteristics low-frequency electromagnetic waves (LFEW) proton gyrofrequency range are studied. excitation these results from relative motion between protons ions, considered as unmagnetized and, therefore, act like a beam...
Plasma and magnetic field data from circular orbits of the Phobos 2 spacecraft near Mars are examined to provide a description plasma properties inner regions magnetosheath boundary layer/plasma mantle. The analyzed in VB coordinate system, which is reasonable for draping magnetospheres nonmagnetized planets comets. It shown that almost impermeable protons formed. ion composition changes at this boundary, transition layer dominated by planetary ions observed. characteristics drastically...
It is well known that the addition of a second ion population into proton‐electron plasma gives rise to new low‐frequency wave modes. Here we investigate stationary structures streaming with sub‐fast speed in such bi‐ion plasma. shown type structure occurs as result mode splitting effects caused by population. These so‐called ‘oscillitons' are characterized an oscillating spatial superimposed on growth or decay associated usual single‐ion solitons. Examples solution full non‐linear equations...
Abstract With a one‐dimensional particle‐in‐cell simulation model, we have investigated the gap formation around 0.5 of quasi‐parallel whistler‐mode waves excited by an electron temperature anisotropy. When frequencies in linear stage cross , or when they are slightly larger than but then drift to lower values, Landau resonance can make distribution form beam‐like/plateau population. Such only changes dispersion relation waves, cause severe damping via cyclotron resonance. At last, wave...
Cluster provides us with a unique possibility to study ULF waves. We analyze wave activity in the near‐Earth upstream solar wind. Using as telescope we investigate detail propagation directions and numbers for various frequencies, obtaining, first time, three dimensional dispersion relations experimentally. After Doppler shift correction, find that are not linear waves propagating sunward direction plasma rest frame. Comparison of experimentally derived relation one beam system shows good...
Abstract. Isotropic electron beams are considered to explain the excitation of whistler waves which have been observed by STEREO satellite in Earth's radiation belt. Aside from their large amplitudes (~240 mV/m), another main signature is strongly inclined propagation direction relative ambient magnetic field. Electron temperature anisotropy with Te⊥>Te||, preferentially generates parallel propagating waves, can be excluded as a free energy source. The instability arises due interaction...
Oscillitons are stationary, nonlinear structures exhibiting spatial oscillations superimposed on the growth and decay which is characteristic of usual solitons. Although they were first identified in plasmas with two ion populations, it shown may generally occur any media a particular wave dispersion, there at least one point diagnostic diagram where phase‐ group velocities coincide finite values k . In this paper, we study properties oscillitons electron whistler branch (‘whistler...
A fully nonlinear theory for stationary whistler waves propagating parallel to the ambient magnetic field in a cold plasma has been developed. It is shown that wave frame proton dynamics must be included self-consistent manner. The complete system of equations can reduced two coupled differential transverse electron or speed and its phase, these possess phase-portrait integral which provides main features system. Exact analytical solutions are found approximation ‘small’ (but nonlinear)...
Perturbation reductive procedures, as used to analyse various weakly nonlinear plasma waves (solitons and periodic waves), normally lead the dynamical system being described by KdV, Burgers' or a Schrödinger-type equation, with properties that can be deduced from an array of mathematical techniques. Here we develop fully theory one-dimensional stationary waves, which elucidates common nature diverse wave phenomena. This is accomplished adopting essentially fluid dynamic viewpoint. In this...
Low Mach number collisionless shocks in a multiple‐ion plasma are investigated theoretically using Rankine‐Hugoniot relations (MIRHR) and hybrid simulations. The derived MIRHR permit tractable solutions for perpendicular shocks. It is found that starting from synchronous flow of mixture different ion species, light ions heavy jump to downstream velocities. Although the resulting differential velocities between species unstable, they produce coherent gyration around each other. This excites...
This paper reports on numerical studies of the generation second-harmonic radiation by a $p$-polarized electromagnetic wave incident an inhomogeneous overdense plasma. Maximum emission coincides with maximum absorption fundamental wave. The importance for structure resonances due to density plateaus near critical layer is demonstrated.
One‐dimensional hybrid code simulations are presented which show that magnetic field depletions of variable length and depht can be maintained over long time in mirror‐stable high‐β plasmas under certain conditions while compressions cannot. This suggests short‐scale holes (MHs), frequently observed space plasmas, may a feature an essentially isotropic rather than mirror‐unstable plasma. suggestion is supported by additional anisotropic reveal localized depressions not typical saturated...
Abstract. It is well known that additional low-frequency waves arise when a second ion population added to plasma normally consisting of protons and electrons. Here, we investigate stationary structures streaming with sub-fast speed in such bi-ion plasma. shown addition the usual "solitons", which have already been described for single-ion plasma, new type structure occurs due population. This associated complex solutions linear dispersion relation certain regions wave number-obliquity...
Magnetic field and plasma measurements on board the Soviet spacecraft Phobos 2 have been analyzed during five elliptical orbits around Mars. The existence of at least one separate boundary an adjacent layer, called planetopause transition region, between bow shock ionopause seems to be a characteristic feature solar wind interaction with almost nonmagnetized planetary ionosphere. It is suggested that multiple‐ion discontinuity, where large number protons are deflected exospheric density...