ELM Mitigation by Supersonic Molecular Beam Injection into the H-mode Pedestal in HL-2A Tokamak
نویسندگان
چکیده
Density profiles in pedestal region (H-mode) are measured in HL-2A and the characteristics of the density pedestal are described. Cold particle deposition by Supersonic Molecular Beam Injection (SMBI) within the pedestal is verified. ELM mitigation by SMBI into the H-mode pedestal is demonstrated and the relevant physics is elucidated. The sensitivity of the effect to SMBI pressure and duration are studied. Following SMBI, the ELM frequency increases and ELM amplitude decreases for a finite duration period. Increases in ELM frequency of SMBI ELM f / 0 ELM f ~ 2-3.5 are achieved. This experiment argues that the ELM mitigation results from an increase in
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