Destruction of the Last Good Surface in Diii-D Usn with ELMs and C-Coils Shot 115467 due to ELMs and C-Coils Using Maps
Abstract
Unperturbed magnetic topology of DIII-D shot 115467 is described by the symmetric simple map (SSM) with parameter k=0.2623, then q_edge=6.48 (as in shot 115467) if six iterations of SSM are taken to be equivalent to single toroidal circuit of DIII-D [1]. Low mn map (LM) calculates effects of m=1, n=+1,-1 modes on trajectories of field lines. We use LM with amplitude ɛ=6X10-4 (value expected in modern divertor tokamaks) to describe effects of ELMs. With ELMs, last good surface passes through x=0, y=0.98375. We use dipole map (DM) to represent effects of C-coils. We apply DM after each iteration of SSM. We use s=1.0021, x_dipole=1.5617, y_dipole= 0 for DIII-D shot 115467 [1]. We study changes in the last good surface and its destruction as function of I_C-coil with fixed ɛ = 6X10-4. This work is supported by NASA SHARP program and DE-FG02-02ER54673. [1] H. Ali, A. Punjabi, A. Boozer, and T. Evans, 31st EPS Plasma Phys Mtg, London, UK, June 29, 2004, paper P2-172.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- November 2004
- Bibcode:
- 2004APS..DPPFP1011S