By making use of the MHD self-induction equation in general relativity (GR), recently derived by Clarkson and Marklund (2005), it is shown that when Friedmann universe possesses a spatial section whose Riemannian curvature is negative, the magnetic energy bounds computed by Nuñez (2002) also bounds the growth rate of the magnetic field given by the strain matrix of dynamo flow. Since in GR-MHD ...

Cross-field particle transport in the scrape-off layer ~SOL! of Alcator C-Mod @Phys. Plasmas 1, 1511 ~1994!# can be characterized by an effective particle diffusivity (Deff) that increases markedly with distance from the separatrix. As a consequence, recycling onto the main-chamber walls is large compared to plasma flows into the divertor volume. The SOL exhibits a two-layer structure: Steep gr...

It is assumed, in general, that the electromagnetic spectrum in the Primordial Universe was a blackbody spectrum in vacuum. We derive the electromagnetic spectrum, based on the Fluctuation-Dissipation Theorem that describes the electromagnetic fluctuations in a plasma. Our description includes thermal and collisional effects in a plasma. The electromagnetic spectrum obtained differs from the bl...

The effect of amplitude fluctuations on reflectometer measurements of density turbulence has been investigated through comparison of reflectometry and Langmuir probes on the CCT and DIII-D tokamaks. Power spectra, turbulent radial correlation lengths, and rootmean square magnitude variations (at the H-mode transition) of the homodyne reflectometer signal (given by SRe = E cos(φ), which depends ...

A simple diagnostic arrangement is suggested for measuring density and temperature fluctuations. The diagnostic uses a cross-correlation technique to extract local frequency spectra, spatial distribution or (in the case of low mode numbers) the mode structure from the chord-average fluctuating intensities of the visible light in the H-l heliac. For low temperature H-l plasmas (T, x 20 eV, n, z ...

Confinement transitions in the Wendelstein 7-AS stellarator [H. Renner et al., Plasma Phys. Control. Fusion 31, 1579 (1989)] can be induced by varying either the internal plasma current or the external magnetic field. In this paper we report on experiments where closely matched confinement states (good and bad) were constructed using the latter method. Analysis using the former scheme has been ...

Citation Hillesheim, J. C. et al. " New plasma measurements with a multichannel millimeter-wave fluctuation diagnostic system in the DIII-D tokamak (invited). " Review of Scientific Instruments 81 (2010): 10D907. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has m...

Turbulent transport in the scrape-off layer of TCV has been investigated by probe measurements and direct comparison with two-dimensional fluid simulations of interchange motions at the outer midplane. The experiments demonstrate that the fluctuation statistics in the region where plasma profiles are broad are invariant with respect to changes in the line-averaged core plasma density. Good agre...

BACKGROUND Complications of diabetes mellitus (DM) are related not only to elevated plasma glucose, but also plasma glucose fluctuations. However, the specific mechanism underlying the role of plasma glucose fluctuation in the pathogenesis of DM complications remains poorly understood. In the present study, the influence of acute fluctuant hyperglycemia and persistent hyperglycemia on vascular ...