Results 261 to 270 of about 23,746 (299)

Relativistic runaway electron avalanche

Uspekhi Fizicheskih Nauk, 2020
Abstract Discussed are the genesis of the concept of the relativistic runaway electron avalanche (RREA) and its mechanism as an analog of the Townsend’s avalanche, but capable of developing, unlike the latter, in weak thundercloud electric fields.
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Relativistic limitations on runaway electrons

Nuclear Fusion, 1975
The non-relativistic theory of a plasma in an electric field E predicts that there will always be runaway electrons, although their number will be exponentially small for fields less than the Dreicer field ED. However, when E/ED ~ kT/mec2, the ratio of the electron thermal energy to the rest mass energy, relativistic effects become important.
J.W. Connor, R.J. Hastie
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Stability of a runaway electron beam

Nuclear Fusion, 1986
The paper studies the distribution function of a runaway electron beam with allowance for close collisions of fast tail electrons with thermal ones, as a result of which momentum is imparted to the latter sufficient for escape into a continuous acceleration regime. It is shown that a beam is formed which is not in equilibrium with respect to transverse
N.T. Besedin, I.M. Pankratov
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A recursive representation for runaway electrons

Journal of Physics A: Mathematical and General, 1982
Among the analytic studies on runaway phenomena the most sophisticated approach to solving the Fokker-Planck equation is to divide the momentum space into five distinct regions with appropriate matching between them: various expansions of the distribution function are valid in different regions. A pair of recursive relations is established to solve the
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RUNAWAY ELECTRONS ON PLASMA FACING COMPONENTS

1993
Runaway electrons can cause severe damage to plasma facing components of large tokamaks. The designs proposed for the first wall and divertor of the next large fusion experiment, ITER (International Thermonuclear Experimental Reactor), are investigated. Energies of up to 300 MeV per electron and surface energy depositions of 30 MJ/m2 are assumed.
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Theory of the Runaway Electron Tail

Physical Review Letters, 1977
The steady-state electron distribution function of a current-carrying magnetized plasma is determined self-consistenly with the enhanced $\ensuremath{\omega}=\frac{{\ensuremath{\omega}}_{\mathrm{pe}}{k}_{\ensuremath{\parallel}}}{k}$ plasma wave spectrum it generates. Consequences include enhanced fluctuations at $\ensuremath{\omega}\ensuremath{\simeq}{\
Kim Molvig, Miloslav S. Tekula, Abraham Bers   +2 more
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Runaway electrons in an impure plasma

The Physics of Fluids, 1976
The electron runaway theories of Kruskal and Bernstein and Lebedev are extended to apply to multiply ionized, multiple species plasmas. The resulting expressions for electron runaway rates are compared with results obtained by Kulsrud, Sun, Winsor, and Fallon from numerical solutions of the Fokker–Planck equation.
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Runaway electrons in toroidal discharges

Nuclear Fusion, 1979
Experimental and theoretical studies of runaway electrons in toroidal devices are reviewed here, with particular reference to tokamaks. The complex phenomenology of runaway effects, which have been the subject of research for the past twenty years, is organized within the framework of a number of physical models.
H. Knoepfel, D.A. Spong
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Gas Ionization by Runaway Electrons

Russian Physics Journal, 2002
A description of the development of a runaway electron avalanche in helium is presented. It is demonstrated that the ionization coefficient α approaches a steady-state value αst even in a very strong field. The dependences of α and αst and also of the transient length of αst on the field strength in the transient region are obtained. The experimentally
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Cross-field runaway electrons

Physical Review A, 1981
The phenomenon of cross-field runaway electrons can occur in cases where large dc electric fields with steep gradients exist perpendicular to a magnetic field. A derivation of the circumstances which permit this condition to exist is presented.
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