Year: 2006
Type: conference-paper
Abstract: The characteristics of electron internal transport barriers (eITBs) in helical systems are reviewed.The common features are highly peaked Te profile with strongly positive Er in the core region.The transition nature of E r based on neoclassical (NC) ambipolarity, with the clear threshold feature such as ECH power and Ohmic current, is the common mechanism for the eITB formation.The electron heat confinement improvement has been revealed within the eITB region.The ECH power threshold can be lowered in the presence of ripple-trapped electrons-induced convective flux, and rational surfaces at the core region.The gyrokinetic calculations, for example eITB in LHD, have shown that the ETG mode is unstable in eITB region due to the large T e gradient.A larger zonal flow amplitude has been observed in eITB phase in CHS.The geodesic transfer of energy from stationary zonal flow to oscillatory modes (GAMs) recognized in H-1 implies that the stationary zonal flows can be maintained at a higher level by reducing the geodesic curvature in helical systems.This is the first report of the eITB branch in the framework of the International Stellarator Profile DataBase (ISPDB).
Source: MPG.PuRe (Max Planck Society)
Authors: Yokoyama, M., Maassberg, H., Ida, K., Estrada, T., Castejon, F., Minami, T., Fujisawa, A., Yamagishi, O., Shats, M. G., Dinklage, A., Tribaldos, V., Beidler, C. D., Shimozuma, T., Takeiri, Y., Herranz, J., Murakami, S., Yamada, H.
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W829628596