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arXiv · 2208.05323

Development of high-frequency magnetic probe for plasma diagnostics of XuanLong-50

Mingyuan Wang·Xiuchun Lun·Xiaokun Bo·Bing Liu·Adi Liu·Yuejiang Shi
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Abstract

A high-frequency magnetic probe has been designed and developed on XuanLong-50 (EXL-50) spherical torus to measure high-frequency magnetic field fluctuations caused by energetic ions and electrons in the plasma. The magnetic loop, radio filters, radio-frequency (RF) limiter, and data acquisition system of the probe are described in detail. The results of the preliminary test show that the probe can have a frequency response within the 1- 180 MHz range. The fluctuation data from the EXL-50 plasma were analyzed in the time-frequency domain using fast Fourier transforms. Using this diagnostic system, distinct high-frequency instabilities were detected. In particular, significant frequency chirping was observed, which is consistent with the bump on tail drive instability predicted by the Berk-Breizman model.

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Mingyuan Wang, Xiuchun Lun, Xiaokun Bo, Bing Liu, Adi Liu, Yuejiang Shi. 2022-08-09. Development of high-frequency magnetic probe for plasma diagnostics of XuanLong-50. https://doi.org/10.1088/2058-6272%2Faca373

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