Confinement at Tight Aspect Ratio in START
Abstract
A series of measurements of the energy confinement time, τE covering a wide variation of parameters has been made in START: R_0 ~0.2-0.35m, a ~0.14-0.29m, A ~1.3, LIM/DND plasmas,I_p=50-250kA, B_T ~0.1-0.4T, T_e(0)=100-1000eV, T_i(0)= 75-350eV and barne between 3×10^18m-3 and 1×10^20m-3. Values of total beta, β_T, and normalised beta, β_N, of ~30% and ~4 respectively have been achieved. Both Ohmic and additionally heated plasmas (using the 1MW, 40keV neutral beam injection system on loan from ORNL) have been studied. Confinement times of several ms have been observed and compared with well known scaling laws eg ITER93H, ITER97H to elucidate the global confinement properties. The results reported here represent the most systematic set of confinement data from any tight aspect ratio tokamak to date and extend the tokamak database to a new domain.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- November 1997
- Bibcode:
- 1997APS..DPPlWP301W