In a world increasingly facing new challenges at the forefront of plasma scientific research and technological innovation, CNR and ISTP pledge progress and achieve an impact in the integration of research into societal practices and policy

Spatial localization of ECE measurement in EAST LHW-heated plasmas

Zuo, Yushu; Liu, Yong; Zhou, Tianfu; Zhao, Hailin; Zhang, Yang; Figini, Lorenzo; Ti, Ang; Ling, Bili; Hu, Liqun

In this work, electron cyclotron emission (ECE) is simulated by using the code SPECE to study the spatial localization of ECE measurement in EAST plasmas heated by lower hybrid wave (LHW). The results indicate that generally there are two emission layers for an individual frequency in plasmas with non-thermal electrons, and they are separately attributed to the thermal electrons and non-thermal electrons. The emission layer due to the thermal electrons is nearly identical to that for the case with Maxwellian distribution. The emission layer due to non-thermal electrons is well localized in the location of the non-thermal electrons. Even though the non-thermal emission layer is broader, the emission intensity is smaller than that from the thermal emission layer for the cases studied in this work. Localized electron temperature fluctuations can still be distinguished by ECE measurement as long as it does not coexist with the non-thermal electrons. Sawtooth inversion radii and tearing mode island location determined respectively by the ECE measurement and the soft x-ray measurement for a LHW-heated plasma show a good agreement, and this indicates that the ECE measurement in the plasma core region is not seriously polluted.

ID 444528
DOI 10.1088/2058-6272/ab247f
PRODUCT TYPE Journal Article
LAST UPDATE 2022-04-06T09:49:46Z