TITLE:
Mitigation of ELMs by Electrostatic Field in Tokamaks
AUTHORS:
Zhongtian Wang, Xiaochang Chen, Yifan Yan, Huidong Li, Qian Liu, Maolin Mou, Na Wu, Zhanhui Wang, Rui Ke, Lin Nie, Ming Xu
KEYWORDS:
Electrostatic Trapping, Bootstrap Current, Mitigation, Peeling-Ballooning Mode
JOURNAL NAME:
Journal of High Energy Physics, Gravitation and Cosmology,
Vol.5 No.1,
December
20,
2018
ABSTRACT: Mitigation of ELMs by electrostatic field is studied. The perpendicular heating in cyclotron waves tends to pile up the resonant particles toward the low magnetic field side in which a electrostatic field may result [J. Y. Hsu, V. S. Chan, R. W. Harvey, R. Prater, and S. K. Wong, Phys. Rev. Lett. 53, 564 (1984)]. The electrostatic field can make circulating particles trapped or make trapped particles circulating depending on the field direction. The trapped- particle population and bootstrap current change accordantly. Modulating bootstrap current, mitigation of type-1 ELM by the electrostatic field is possible. The electrostatic potential needed for the mitigation is quantitatively estimated. Experiments by either ECRH or biasing are being prepared to verify the theory.