Comparison of Hydrogen and Deuterium Plasmas in ECH Start-Up Experiment in the TST-2 Spherical Tokamak

Osamu WATANABE, Akira EJIRI, Hiroki KURASHINA, Takuya OHSAKO, Yoshihiko NAGASHIMA, Takashi YAMAGUCHI, Takuya SAKAMOTO, Byung Il AN, Hiroyuki HAYASHI, Hiroaki KOBAYASHI, Kotaro YAMADA, Hidetoshi KAKUDA (+4 others)
2010 Plasma and Fusion Research  
In the TST-2 spherical tokamak, non-inductive start-up experiment using electron cyclotron heating (ECH) at 2.45 GHz are performed. Hydrogen and deuterium discharges were compared after sufficient wall cleaning by Ohmic discharges to ensure discharge reproducibility. After the wall cleaning, wall recycling seemed to be reduced, because additional gas puffing was necessary to sustain a discharge. Even in that case, hydrogen emission measurement revealed the existence of finite wall recycling
more » ... ce. A current jump occurred earlier in the deuterium plasma than in the hydrogen plasma. Except for the timing of the jump, the discharge time evolution and various values such as the plasma current were almost the same for the deuterium and hydrogen plasmas.
doi:10.1585/pfr.5.s2032 fatcat:m3l43d4hebaudgtlb3mwg6nyiy