Andrey A. Kabantsev

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A new asymmetry-induced transport mechanism in pure electron plasmas is shown to be proportional to the damping rate of the corresponding trapped-particle mode, with simple scalings for all other parameters. This transport occurs when axial particle trapping exists due to variations in the electric or magnetic confinement fields. This new transport is(More)
Trapped particle modes and the associated asymmetry-induced transport are characterized experimentally in cylindrical electron plasmas. Axial variations in the electric or magnetic confinement fields cause the particle trapping, and enable the E3B drift trapped-particle modes. Collisional diffusion across the trapping separatrix causes the modes to damp,(More)
Weak axial variations in magnetic or electric confinement fields in pure electron plasmas cause slow electrons to be trapped locally, and collisional diffusion across the trapping separatrix then causes surprisingly large trapped-particle-mediated (TPM) damping and transport effects. Here we characterize TPM damping of m theta not equal to 0, m(z) = +/-1(More)
Resonant drift-wave coupling experiments characterize a new dissipative coupling term caused by a trapping separatrix. The system is a cylindrical pure-electron plasma with an axial trapping separatrix generated by an applied theta-symmetric wall voltage. The resonant decay of m_{theta}=2 diocotron modes into m_{theta}=1 trapped-particle diocotron modes is(More)
Weak axial variations in B(z) or φ(z) in Penning-Malmberg traps cause some particles to be trapped locally. This causes a velocity-space separatrix between trapped and passing populations, and collisional separatrix diffusion then causes mode damping and asymmetry-induced transport. This separatrix dissipation scales with collisionality as ν1/2, so it(More)
Novel trapped-particle asymmetry modes propagate on cylindrical electron columns when axial variations in the wall voltage cause particle trapping. These modes consist of E x B drifts of edge-trapped particles, partially shielded by axial flows of interior untrapped particles. A simple model agrees well with the observed frequencies and eigenfunctions, but(More)
The damping mechanism of a recently discovered trapped-particle mode is identified as collisional velocity scattering of marginally trapped particles. The mode exists on non-neutral plasma columns that are partially divided by an electrostatic potential. This damping mechanism is similar to that responsible for damping of the dissipative trapped-ion mode.(More)
Experiments and theory characterize a parametric decay instability between plasma drift waves when the nonlinear coupling is modified by an electrostatic barrier. Novel mode coupling terms representing enhanced dissipation and mode phase shifts are caused by chaotic separatrix crossings on the wave-ruffled separatrix. Experimental determination of these(More)
Weak axial variations in B(z) or φ(z) in “axisymmetric” plasma traps cause a fraction of the particles to be trapped axially, with a velocity-space separatrix between trapped and passing populations. The trapped and passing particles experience different dynamics in response to a variety of θ-asymmetries in the E × B rotating plasma, so a discontinuity in(More)
Pure electron plasma experiments characterize a novel form of algebraic diocotron mode damping, distinct from the usual exponential damping. This algebraic damping occurs when trap asymmetries cause a weak outward particle flux Γ(r) through the diocotron mode resonant radius rm. The m = 1 and m = 2 diocotron mode amplitudes are each observed to decay as(More)