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Tham khảo tài liệu 'wave propagation 2011 part 14', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | IV. Wave Propagation in Plasma. 19 Interplay of Kinetic Plasma Instabilities M. Lazar1 2 S. Poedts2 and R. Schlickeiser3 1Research Department - Plasmas with Complex Interactions Ruhr-Universitãt Bochum D-44780 Bochum 2Centre for Plasma Astrophysics Celestijnenlaan 200B 3001 Leuven 3Institut fur Theoretische Physik Lehrstuhl IV Weltraum- und Astrophysik Ruhr-Universitãt Bochum D-44780 Bochum 13Germany 2Belgium 1. Introduction Undulatory phenomena are probably among the most fascinating aspects of our existence. It is well known that plasma is the most dominant state of ionized matter in the Universe. Moreover it can excite and sustain any kind of oscillatory motion acoustic or electromagnetic light waves. A realistic perspective upon the dynamics of space or laboratory plasmas reveals a constant presence of various kinetic anisotropies of plasma particles like beams or temperature anisotropies. Such anisotropic plasma structures give rise to growing fluctuations and waves. The present chapter reviews these kinetic instabilities providing a comprehensive analysis of their interplay for different circumstances relevant in astrophysical or laboratory applications. Kinetic plasma instabilities are driven by the velocity anisotropy of plasma particles residing in a temperature anisotropy or in a bulk relative motion of a counter streaming plasma or a beam-plasma system. The excitations can be electromagnetic or electrostatic in nature and can release different forms of free energy stored in anisotropic plasmas. These instabilities are widely invoked in various fields of astrophysics and laboratory plasmas. Thus the so-called magnetic instabilities of the Weibel-type Weibel 1959 Fried 1959 can explain the generation of magnetic field seeds and the acceleration of plasma particles in different astrophysical sources e.g. active galactic nuclei gamma-ray bursts Galactic micro quasar systems and Crab-like supernova remnants where the nonthermal radiation originates Medvedev .
