G. Manfredi R. O. Dendy
Test-particle transport arising from E 3 B motion in a turbulent plasma is investigated numerically. The electrostatic field is determined by solving the Hasegawa-Mima model for two-dimensional drift turbulence. In the linear regime the particles experience stochastic diffusion, but in the fully nonlinear, strongly turbulent regime the diffusion ra…
PublishedG. Manfredi R. O. Dendy
The diffusion of test particles in a turbulent electrostatic field is investigated numerically. The field is obtained by solving the Hasegawa–Mima model for two-dimensional drift turbulence. It is shown that nonlinear coupling significantly reduces the level of transport compared to the linear regime, and the physical mechanisms leading to this e…
PublishedR. Guerra J. T. Mendonça R. O. Dendy P. K. Shukla
The scattering of electromagnetic waves from counter-rotating vortex streets associated with nonlinear convective cells in uniform plasmas has been considered. The vortex street solution of the Navier–Stokes or the Hasegawa–Mima (and of the ‘‘sinh-Poisson’’) equation is adopted as a scatterer. Assuming arbitrary polarization and profile…
PublishedK. G. McClements R. O. Dendy C. N. Lashmoredavies G. A. Cottrell S. Cauffman et al.
Ion cyclotron emission ~ ICE ! has been observed during neutral beam-heated supershots in the Tokamak Fusion Test Reactor ~ TFTR ! @ Phys. Rev. Lett. 72 , 3526 ~ 1994 !# deuterium–tritium campaign at fusion product cyclotron harmonics. The emission originates from the outer midplane edge plasma, where fusion products initially have an anisotropic…
PublishedG. Manfredi M. Shoucri R. O. Dendy A. Ghizzo P. Bertrand
An Eulerian code that solves the gyrokinetic Vlasov equation in slab geometry is presented. It takes into account the E X B and polarization drifts in the plane perpendicular to the magnetic field, and kinetic effects in the parallel direction. The finite Larmor radius is modelled by a convolution operator. The relation is established between this …
PublishedR. O. Dendy R. J. Hastie K. G. McClements T. J. Martin
A generalized energy principle is used to determine the effect of ion cyclotron resonant heating (lCRH) on the stability of m = 1 intemal kink displacements in the low-frequency limit: such displacements are associated with sawtooth oscillations. An integral expression is obtained for the contribution to the plasma energy of an ICRH-heated minority…
PublishedD. C. Mcdonald R. A. Cairns C. N. Lashmore-Davies
When a wave passes through an electron gyroresonance, in a plasma in the presence of a magnetic field gradient, there is a small spread in the resonance due to the electron's Larmor radius. Mathematically this is represented by the inclusion of the so called gyrokinetic term in the resonance condition, Lashmore-Davies and Dendy 1. The smallness of …
PublishedR. O. Dendy C. N. Lashmoredavies K. F. Kam
The magnetoacoustic cyclotron instability is a mechanism by which waves on the perpendicular fast Alfvén-ion Bernstein branch can be excited through cyclotron resonance with an energetic ion population. It is a candidate emission mechanism for the superthermal ion cyclotron radiation, apparently associated with the products of fusion reactions, th…
PublishedC. N. LashmoreDavies V. Fuchs R. O. Dendy
A full-wave equation has been obtained from the gyrokinetic theory for the fast wave traversing a minority cyclotron resonance [Phys. Fluids B 4, 493 ( 1992)] with the aid of the fast wave approximation [Phys. Fluids 31, 1614 (1988)]. This theory describes the transmission, reflection, and absorption of the fast wave for arbitrary values of the par…
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