Loading...
Please wait, while we are loading the content...
Similar Documents
Relation among Potential , Fluctuation Change and LH Transition in the JFT-2 M Tokamak
| Content Provider | Semantic Scholar |
|---|---|
| Author | Miura, Yukitoshi Kamiya, Kensaku Hamada, Yasuji |
| Copyright Year | 2000 |
| Abstract | Potential and density/temperature fluctuation at L-H transition are measured by the heavy ion beam probe (HIBP) on JFT-2M. It has been observed that the time scale of potential change is as fast as 10-100μs when the input power (Pin) is larger than the L-H threshold power (P th). When Pin~Pth, the confinement is improved gradually step by step with sawteeth crashes accompanied with the decrease of potential. After a few sawteeth crashes, potential drops rapidly to the level of the ELM-free H-mode. From the gradual change of the potential with assuming that dEr/dr is a key to form and to sustain the transport barrier, the criterion of the dEr/dr is less than (1.2 ± 0.4)×10 kV/m. At an ELM just before H-L transition, the potential inside the separatrix also shows the rapid positive jump. The time scale of the positive jump and its recover to its negative value is about 40μsec and 150μsec, respectively. Before the H-L transition, the time between ELMs and/or dithering transition becomes shorter and the plasma finally goes back to L-mode. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www-pub.iaea.org/MTCD/Publications/PDF/csp_008c/pdf/ex2_7.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
