Experimental characterization of drift-wave turbulence in the sheared, cylindrical slab
| dc.contributor.advisor | Gentle, Kenneth W. | en |
| dc.creator | Lee, Kevin Michael | en |
| dc.date.accessioned | 2011-03-24T14:21:17Z | en |
| dc.date.accessioned | 2017-05-11T22:21:43Z | |
| dc.date.available | 2011-03-24T14:21:17Z | en |
| dc.date.available | 2017-05-11T22:21:43Z | |
| dc.date.issued | 2009-05 | en |
| dc.description | text | en |
| dc.description.abstract | Plasma turbulence on a uniform density gradient with unfavorable magnetic curvature is investigated extensively in the Helimak device. The turbulence is strong with density and electrostatic potential fluctuation levels in excess of 40%. Measurements of the dispersion relation, k[subscript z], and k[subscript parallel lines] identify the the fluctuations with drift-waves, which propagate in the poloidal direction at the diamagnetic drift velocity and have a small, but nite parallel wavenumber. A non-zero phase shift between the density and potential fluctuations gives rise to turbulent cross-eld particle transport, which is measured using spectral techniques. In addition, the electrostatic drift-wave fluctuations have a small magnetic component that is driven by the turbulent parallel current [scientific symbols]. An examination of nonlinear processes associated with the plasma turbulence uncovers high levels of intermittency near the plasma edge and long-time persistence of the density fluctuations on the order of the parallel confinement time. An analysis of the bispectrum conrms the existence local and nonlocal three-wave interactions between unstable drift-waves although the turbulent saturation of the density fluctuation spectrum is likely due nonlinear processes acting in the time domain. | en |
| dc.description.department | Physics | en |
| dc.format.medium | electronic | en |
| dc.identifier.uri | http://hdl.handle.net/2152/10671 | en |
| dc.language.iso | eng | en |
| dc.rights | Copyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works. | en |
| dc.subject | Plasma turbulence | en |
| dc.subject | Density gradient | en |
| dc.subject | Magnetic curvature | en |
| dc.subject | Drift-waves | en |
| dc.title | Experimental characterization of drift-wave turbulence in the sheared, cylindrical slab | en |