Role of the q Profile in Electron ITB Evolution in JET Discharges
Investigation of electron Internal Transport Barriers (eITB) in experiments with dominant electron heating is a subject of detailed analysis on different tokamaks due to a possibility to use this plasma as a prototype of a reactor relevant condition with prevailing electron heating by alpha particles. A link between eITB dynamics and peculiarities of safety factor profile, q(r), is discussed in many recent papers (see, for example, [1-3] and references therein). However there is no common opinion about the role of the magnetic shear in eITB formation and evolution. Previous JET results focused on eITB physics [4,5] have shown that electron ITB is located in reversed shear area just inside the qmin position. Turbulence stability analysis performed in  showed that magnetic shear value of s<-0.5 is a favourable condition for eITB formation due to Dissipative Trapped Electron mode stabilisation. The goal of this paper is an investigation of q(r) profile influence on eITB formation and evolution in JET discharges with dominant electron heating. Magnetic shear effect in the eITB triggering will be emphasised.
Bibliographic Reference: An oral paper given at: 31st EPS Conference on Controlled Fusion and Plasma Physics Organised by: CCLRC Rutherford Appleton Laboratory (GB) Held at: Imperial College London (GB)
Availability: Available from Association EURATOM-CEA, Département de Recherches sur la Fusion Contrôlée, CEA Cadarache, F-13108 St Paul-Lez-Durance, France Tel: (+33) 4 42 25 70 01; Fax: (+33) 4 42 25 64 21 E-mail: email@example.com
Record Number: 200517998 / Last updated on: 2005-03-15
Original language: en
Available languages: en