July 2011

Journal

First observation of ELM pacing with vertical jogs in a spherical torus

By:
Gerhardt, S.P.; Ahn, Joonwook ; Canik, John M; Maingi, Rajesh ; Bell, R. E.; Gates, D.; Goldston, R.; Hawryluk, R.; Le Blanc, B.; Menard, J.; Sontag, Aaron C; Sabbagh, S. A.; Tritz, K.
Journal Name:
Nuclear Fusion
Page Number:
064015
Volume:
50
Issue Number:
6
Publication Date:
July 2011
View DOI Listing:
https://doi.org/10.1088/0029-5515/50/6/064015

Abstract

Experiments in a number of conventional aspect ratio tokamaks have been successful in pacing edge localized modes (ELMs) by rapid vertical jogging of the plasma. This paper demonstrates the first pacing of ELMs in a spherical torus plasma. Applied 30 Hz vertical jogs synchronized the ELMs with the upward motion of the plasma. 45 Hz jogs also lead to an increase in the ELM frequency, though the synchronization of the ELMs and jogs was unclear. A reduction in the ELM energy was observed at the higher driven ELM frequencies.