Trapped particles and asymmetry-induced transport
نویسندگان
چکیده
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, and causes bulk radial transport when the confinement fields also have u asymmetries. The measured asymmetry-induced transport rates are directly proportional to the measured mode damping rates, with simple scalings for all other plasma parameters. Significant transport is observed for even weak trapping fields (dB/B;10), possibly explaining the ‘‘anomalous’’ background transport observed so ubiquitously in single species plasmas. © 2003 American Institute of Physics. @DOI: 10.1063/1.1564089#
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