Initial experiments on asymmetry-induced transport in the Occidental non-neutral plasma trap found the radial particle flux at small radii to be proportional to phi(a)(2), where phi(a) is the applied asymmetry amplitude. Other researchers, however, using the global expansion rate as a measure of the transport, have observed a phi(a)(1) scaling when the rigidity (the ratio of the axial bounce frequency to the azimuthal rotation frequency) is in the range of 1-10. In an effort to resolve this discrepancy, measurements have been extended to different radii and asymmetry frequencies. Although the results to date are generally in agreement with those previously reported (phi(a)(2) scaling at low asymmetry amplitudes falling off to a weaker scaling at higher amplitudes), some cases have been observed where the low amplitude scaling is closer to phi(a)(1). Both the phi(a)(2) and phi(a)(1) cases, however, have rigidities less than 10. Instead, the phi(a)(1) cases are characterized by an induced flux that is comparable in magnitude but opposite in sign to the background flux. This suggests that the mixing of applied and background asymmetries plays an important role in determining the amplitude scaling of this transport. (C) 2002 American Institute of Physics. [References: 14]
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