Analysis of sawtooth collapse time using electron cyclotron emission imaging on EAST tokamak. Issue 9 (3rd October 2017)

• Record Type: Journal Article
• Authors: Zhao, Zhenling; Xie, Jinlin; Qu, Chengming; Liao, Wang; Li, Hong; Lan, Tao; Liu, Adi; Zhuang, Ge; Liu, Wandong
• Is Part Of: Radiation effects and defects in solids. Volume 172:Issue 9/10(2017)
• Page Start: 760
• Page End: 767
• Publication Date: 2017-10-03
• Subjects: ECEI -- EAST tokamak -- sawtooth instability -- collapse time -- heat flux; Radiation chemistry -- Periodicals; Crystals -- Defects -- Periodicals; Crystal lattices -- Periodicals; 530.416
• DOI: 10.1080/10420150.2017.1398751
• Languages: English
• ISSNs: 1042-0150

Abstract

ABSTRACT: Electron cyclotron emission imaging (ECEI), as an advanced diagnostic, provides two-dimensional (2D) images of electron temperature fluctuation in the core plasma region. The ECEI system on Experimental Advanced Superconducting Tokamak (EAST) tokamak consists of 384 channels by 24 (vertical) × 16 (horizontal). The system nearly covers the whole surface in cross-section of EAST. Here, we present a quantitative method to estimate the sawtooth collapse time. All of the electron temperature fluctuations inside the surface are summed up, and the collapse time is estimated as the time lag between the maximum and minimum values of the total fluctuation during one sawtooth cycle. Using this method, statistical analysis of sawtooth behaviors is studied in the EAST Ohmic heating plasma. Relationships of heat flux, sawtooth period and collapse time are also presented.