Download or read book Shear Alfven Waves in Gyrokinetic Plasmas written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: It is found that the thermal fluctuation level of the shear-Alfven waves in a gyrokinetic plasma decreases with plasma b(* cs2/uA2), where cs is the ion acoustic speed and uA is the Alfven velocity. This unique thermodynamic property based on the fluctuation-dissipation theorem is verified in this paper using a new gyrokinetic particle simulation scheme, which splits the particle distribution function into the equilibrium part as well as the adiabatic and nonadiabatic parts.

Download or read book Alfven Waves in Gyrokinetic Plasmas written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A brief comparison of the properties of Alfven waves that are based on the gyrokinetic description with those derived from the MHD equations is presented. The critical differences between these two approaches are the treatment of the ion polarization effects. As such, the compressional Alfven waves in a gyrokinetic plasma can be eliminated through frequency ordering, whereas geometric simplifications are needed to decouple the shear Alfven waves from the compressional Alfven waves within the context of MHD. Theoretical and numerical procedures of using gyrokinetic particle simulation for studying microturbulence and kinetic-MHD physics including finite Larmor radius effects are also presented.

Download or read book An Introduction to Alfven Waves written by Rodney Cross and published by CRC Press. This book was released on 1988-11 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: This valuable introduction to the physics of Alfven waves in laboratory and space plasmas is accessible to anyone with a elementary knowledge of plasma physics. The book will give graduate students all the background information necessary to understand the research literature. Much of the material is recent and may contain some surprises even for experts.

Download or read book Shear Alfvn Waves in Gyrokinetic Plasmas written by W. W. Lee and published by . This book was released on 2000 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gyrokinetic Particle Simulations of Reversed Shear Alfv n Eigenmodes in Fusion Plasmas written by Wenjun Deng and published by . This book was released on 2011 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: A nonlinear gyrokinetic simulation model, which recovers the ideal magnetohydrodynamic (MHD) theory in the linear long-wavelength regime is formulated for studying kinetic MHD processes in magnetized plasmas. This comprehensive formulation enables gyrokinetic simulation of both pressure gradient-driven and current-driven instabilities including ideal and kinetic ballooning modes, kink modes, and shear Alfvén waves, as well as their nonlinear interactions in multi-scale simulations. Implemented in the gyrokinetic toroidal code (GTC), the new formulation is verified in simulations of reversed shear Alfvén eigenmode (RSAE) in fusion plasmas. The antenna excitation of RSAE provides verifications of its mode structure, frequency and damping rate from the initial perturbation simulation with kinetic thermal ions. When excited by fast ions, their non-perturbative contributions modify the mode structure relative to the ideal MHD theory. With inclusion of thermal plasma pressure, the mode frequency increases due to the elevation of the Alfvén continuum by the geodesic compressibility. The GTC simulations have been benchmarked with extended hybrid MHD-gyrokinetic simulations. The verified gyrokinetic simulation model is applied to studying the linear properties of RSAE driven by density gradient of neutral beam injected fast ions in a well-diagnosed DIII-D tokamak experiment (discharge #142111). GTC simulations find that weakly damped RSAE exists due to toroidal coupling and other geometric effects. Various damping and driving mechanisms are identified and measured in the simulations, which shows that accurate damping and growth rate calculation requires true mode structure from non-perturbative, fully self-consistent simulation. The mode structure has no up-down symmetry mainly due to the radial symmetry breaking by the radial variation of fast ion density gradient, as measured in the experiment by electron cyclotron emission imaging. The RSAE frequency up-sweeping and the mode transition from RSAE to toroidal Alfvén eigenmode are in good agreement with the experimental results when scanning the values of the minimum safety factor in simulations. Good agreements in frequencies, growth rates, and mode structures are obtained among simulations of gyrokinetic codes GTC and GYRO, and an MHD-hybrid code TAEFL, which provide further verification and validation of the gyrokinetic model for simulating the kinetic MHD processes. As a prelude to nonlinear simulations of RSAE and associated fast ion transport, properties of microturbulence in reversed shear plasmas are also studied.

Download or read book Nonlinear Gyrokinetic Equations for Low frequency Electromagnetic Waves in General Plasma Equilibria written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A nonlinear gyrokinetic formalism for low-frequency (less than the cyclotron frequency) microscopic electromagnetic perturbations in general magnetic field configurations is developed. The nonlinear equations thus derived are valid in the strong-turbulence regime and contain effects due to finite Larmor radius, plasma inhomogeneities, and magentic field geometries. The specific case of axisymmetric tokamaks is then considered, and a model nonlinear equation is derived for electrostatic drift waves. Also, applying the formalism to the shear Alfven wave heating sceme, it is found that nonlinear ion Landau damping of kinetic shear-Alfven waves is modified, both qualitatively and quantitatively, by the diamagnetic drift effects. In particular, wave energy is found to cascade in wavenumber instead of frequency.

Download or read book Simulations of Reversed Shear Alfv n Eigenmodes in Fusion Plasmas written by Wenjun Deng and published by LAP Lambert Academic Publishing. This book was released on 2012-07 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: In fusion plasmas, generated from heating sources or fusion products, energetic particles can excite Alfven eigenmodes, which undermines energetic particle confinement. To reduce or avoid this problem, behaviors of energetic particles and Alfven eigenmodes need to be studied in detail. In this book, a nonlinear gyrokinetic simulation model, which recovers the ideal magnetohydrodynamic (MHD) theory in the linear long-wavelength regime, is formulated for studying kinetic MHD processes in magnetized plasmas. This comprehensive formulation enables gyrokinetic simulation of both pressure gradient-driven and current-driven instabilities including ideal and kinetic ballooning modes, kink modes, and shear Alfven waves, as well as their nonlinear interactions in multi-scale simulations. Implemented in the gyrokinetic toroidal code (GTC), the new formulation is verified in simulations of reversed shear Alfven eigenmode (RSAE). The verified model is then applied to studying the linear properties of RSAE driven by density gradient of neutral beam injected fast ions in a well-diagnosed DIII-D tokamak experiment.

Download or read book Shear Alfv n Waves in Two Ion Plasmas Polarization Dispersion and Species Mix Diagnostic written by Jeffrey Scott Robertson and published by . This book was released on 2020 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Waves and Instabilities in Plasmas written by Liu Chen and published by World Scientific. This book was released on 1987 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topics covered in these notes are selective and tend to emphasize more on kinetic-theory approaches to waves and instabilities in both uniform and non-uniform plasmas, students are assumed to have some basic knowledge of plasma dynamics in terms of single-particle and fluid descriptions.

Download or read book Gyrokinetic Analysis of Low n Shear Alfv n and Ion Sound Wave Spectra in a High beta Tokamak Plasma written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Waves and Oscillations in Plasmas written by Hans Laszlo Pecseli and published by Taylor & Francis. This book was released on 2016-04-19 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: Winner of an Outstanding Academic Title Award from CHOICE Magazine The result of more than 15 years of lectures in plasma sciences presented at universities in Denmark, Norway, and the United States, Waves and Oscillations in Plasmas addresses central issues in modern plasma sciences. The book covers fluid models as well as kinetic plasma mode

Download or read book Plasma Waves written by D.G. Swanson and published by Elsevier. This book was released on 2012-12-02 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. These chapters also describe the averaging process for the fluid element motion using expanded Boltzmann equation for each species in a velocity moment expansion, truncating the expansion at some suitable level, depending on the particular problem. The remaining four chapters discuss the effects of adding sharp boundaries, slowly varying inhomogeneities, nonlinearities at several levels, and turbulent plasmas. Supplementary texts on complex variables and the special functions in plasma physics are provided in the concluding section of this text. The book is an advanced text for graduate students who have had an introductory plasma course at some level.

Download or read book Kinetic Alfv n Waves in Laboratory Space and Astrophysical Plasmas written by De-Jin Wu and published by Springer Nature. This book was released on 2020-01-07 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a systematic introduction to the observation and application of kinetic Alfven waves (KAWs) in various plasma environments, with a special focus on the solar-terrestrial coupling system. Alfven waves are low-frequency and long-wavelength fluctuations that pervade laboratory, space and cosmic plasmas. KAWs are dispersive Alfven waves with a short wavelength comparable to particle kinematic scales and hence can play important roles in the energization and transport of plasma particles, the formation of fine magneto-plasma structures, and the dissipation of turbulent Alfven waves. Since the 1990s, experimental studies on KAWs in laboratory and space plasmas have significantly advanced our understanding of KAWs, making them an increasingly interesting subject. Without a doubt, the solar–terrestrial coupling system provides us with a unique natural laboratory for the comprehensive study of KAWs. This book presents extensive observations of KAWs in solar and heliospheric plasmas, as well as numerous applications of KAWs in the solar-terrestrial coupling system, including solar atmosphere heating, solarwind turbulence, solar wind-magnetosphere interactions, and magnetosphere-ionosphere coupling. In addition, for the sake of consistency, the book includes the basic theories and physical properties of KAWs, as well as their experimental demonstrations in laboratory plasmas. In closing, it discusses possible applications of KAWs to other astrophysical plasmas. Accordingly, the book covers all the major aspects of KAWs in a coherent manner that will appeal to advanced graduate students and researchers whose work involves laboratory, space and astrophysical plasmas.

Download or read book The Theory of Plasma Waves written by Thomas Howard Stix and published by . This book was released on 1962 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Current Driven Instabilities of the Kinetic Shear Alfven Wave written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The kinetic Alfven wave is studied in a cylindrical force-free plasma with self-consistent magnetic fields. This equilibrium represents a reversed field pinch or a spheromak. The stability of the wave is found to depend on the ratio of the electron drift velocity to the Alfven velocity. This ratio varies inversely with the square root of the plasma line density. The critical line density using the Spitzer-Harm electron distribution function is found for reversed field pinches with deuterium plasmas to be approximately 2 x 1018 m−1 and is 5 x 1017 m−1 in spheromaks with hydrogen plasmas. The critical line density is in reasonable agreement with experimental data for reversed field pinches.

Download or read book Turbulent Transport In Magnetized Plasmas Second Edition written by C Wendell Horton, Jr and published by #N/A. This book was released on 2017-07-21 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: For a few seconds with large machines, scientists and engineers have now created the fusion power of the stars in the laboratory and at the same time find the rich range of complex turbulent electromagnetic waves that transport the plasma confinement systems. The turbulent transport mechanisms created in the laboratory are explained in detail in the second edition of 'Turbulent Transport in Magnetized Plasmas' by Professor Horton.The principles and properties of the major plasma confinement machines are explored with basic physics to the extent currently understood. For the observational laws that are not understood — the empirical confinement laws — offering challenges to the next generation of plasma students and researchers — are explained in detail. An example, is the confinement regime — called the 'I-mode' — currently a hot topic — is explored.Numerous important problems and puzzles for the next generation of plasma scientists are explained. There is growing demand for new simulation codes utilizing the massively parallel computers with MPI and GPU methods. When the 20 billion dollar ITER machine is tested in the 2020ies, new theories and faster/smarter computer simulations running in near real-time control systems will be used to control the burning hydrogen plasmas.

Download or read book Solitary Waves in Plasmas and in the Atmosphere written by Vladimir .I. Petviashvili and published by Routledge. This book was released on 2016-04-15 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: First Published in 1992. This book arose as a result of the authors work on the review ‘Solitary Vortices in Plasmas’ written for the Soviet Journal of Plasma Physics. With the development of nonlinear wave theory some novel concepts came into use, such as solitary waves, solitary vortices, and solitons. There is still some inconsistency in the use of these terms. The study of solitary waves (solitons) should ultimately lead to a better understanding of the internal structure of elementary particles. That is why solitons are attracting great attention from physicists and mathematicians. The material presented in this book shows that solitons are also of interest in plasma physics and geophysics, where these concepts have many important applications.