Electron energy distribution function in the divertor region of the COMPASS tokamak

19th International Summer School on Vacuum, Electron and Ion Technologies

Dimitrova, M.^1,2 ; Hasan, E.^2,3 ; Ivanova, P.^2 ; Vasileva, E.^2 ; Popov, Tsv^3 ; Dejarnac, R.^1 ; Stöckel, J.^1 ; Panek, R.^1

Institute of Plasma Physics, Academy of Sciences of the Czech Republic, 3 Za Slovankou, Prague 8

182 00, Czech Republic^1

Acad. E. Djakov Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Sofia

1784, Bulgaria^2

Faculty of Physics, St. Kl. Ohridski University of Sofia, 5 J. Bourchier Blvd., Sofia

1164, Bulgaria^3

关键词: Divertor region;    Electron energy distribution functions;    High field sides;    Hydrogen discharge;    Low energy electrons;    Low-field sides;    Plasma parameter;    Toroidal magnetic fields;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/700/1/012009/pdf
DOI  :  10.1088/1742-6596/700/1/012009

来源: IOP

【 摘 要 】

The plasma parameters during an L-mode hydrogen discharge in the COMPASS tokamak with a toroidal magnetic field BT=1.15 T, line-averaged electron density ne= 6×1019m-3and a plasma current variation from 209 kA to 100 kA were studied in the divertor region. The electron energy distribution function for 209 kA at the high-field side and the private region is Maxwellian with a temperature in the range of 5 - 9 eV, while around the outer strike point and the low-field side it is bi-Maxwellian with a low-energy electron group (4 - 5 eV) and higher energy electrons (10 - 20 eV). As the plasma current decreases, the appearance of the bi-Maxwellian EEDF is shifted towards the low-field side; at plasma current of 100 kA, the EEDF is Maxwellian in the whole divertor region.