DIFFER
DIFFER Publication

Ion heat transport studies in JET

Author
Abstract

Detailed experimental studies of ion heat transport have been carried out in JET exploiting the upgrade of active charge exchange spectroscopy and the availability of multi-frequency ion cyclotron resonance heating with (3)He minority. The determination of ion temperature gradient (ITG) threshold and ion stiffness offers unique opportunities for validation of the well-established theory of ITG driven modes. Ion stiffness is observed to decrease strongly in the presence of toroidal rotation when the magnetic shear is sufficiently low. This effect is dominant with respect to the well-known omega(ExB) threshold up-shift and plays a major role in enhancing core confinement in hybrid regimes and ion internal transport barriers. The effects of T(e)/T(i) and s/q on ion threshold are found rather weak in the domain explored. Quasi-linear fluid/gyro-fluid and linear/non-linear gyro-kinetic simulations have been carried out. Whilst threshold predictions show good match with experimental observations, some significant discrepancies are found on the stiffness behaviour.

Year of Publication
2011
Journal
Plasma Physics and Controlled Fusion
Volume
53
Number
12
Issue
12
Number of Pages
124033
Date Published
Dec
Type of Article
Article
ISBN Number
0741-3335
DOI
10.1088/0741-3335/53/12/124033
PId
3e267c444cd4d79c851bd379feaeb938
Alternate Journal
Plasma Phys. Control. Fusion
Label
OA
Attachment
Journal Article
Download citation