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2013
Many models for anomalous transport consider the turbulent E × B transport arising from electrostatic micro-instabilities. In this paper we investigate whether the perturbed magnetic field that is associated with such instabilities at small but finite values of ß can lead to significant stochastic magnetic field transport. Using the tearing parit…
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2012
Lower hybrid current drive (LHCD) with modest powers ( 10% of the total power input) has been used for the first time to completely stabilize performance limiting neoclassical tearing modes in many COMPASS-D tokamak discharges. The stabilizing effect in these experiments is consistent with a reduction in the free energy available in the current pro…
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2012
A numerical study is carried out, based on a simple toroidal tokamak equilibrium, to demonstrate the radial re-distribution of the electromagnetic torque density, as a result of a rotating resistive plasma (linear) response to a static resonant magnetic perturbation field. The computed electromagnetic torque peaks at several radial locations even i…
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2012
Two methods for calculating tearing mode stability are described in this paper. A fast method using the recently improved T7 code (Ham et al. 2012 Plasma Phys. Control. Fusion 54 025009) and a new method based on the MARS-F MHD stability code (Liu et al. 2000 Phys. Plasmas 7 3681) which constructs the tearing mode solution from calculated basis fun…
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2012
It is shown that in perfectly quasi-isodynamic stellarators, trapped particles with a bounce frequency much higher than the frequency of the instability are stabilizing in the electrostatic and collisionless limit. The collisionless trapped-particle instability is therefore stable as well as the ordinary electron-densitygradient- driven trapped-ele…
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2012
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2012
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2012
Within the single fluid theory for a toroidal, resistive plasma, the favorable average curvature effect [Glasser et al. , Phys. Fluids 18 , 875 (1975)], which is responsible for the strong stabilization of the classical tearing mode at finite pressure, can also introduce a strong screening effect to the externally applied resonant magnetic field. C…
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2011
It is well known that stabilization of the resistive wall mode (RWM) may allow fusion power to be significantly increased for a given magnetic field in advanced tokamak operation. The principle of stabilization of the RWM by rotation has been established both experimentally and theoretically. Recent experimental results have indicated stabilization…
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2011
Stabilization of the resitive wall mode (RWM) may allow fusion power to be doubled for a given magnetic field in advanced tokamak operation. Experimental evidence from DIII-D and other machines suggests that plasma rotation can stabilize the RWM. Several authors (Finn 1995 Phys. Plasmas 2 3782, Bondeson Xie 1997 Phys. Plasmas 4 2081) have construct…
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