Design of windows for multi-scale turbulence collective scattering diagnostic system on HL-3 Tokamak

Hou Zhipei; Deng Bihe; Chen Chengyuan; Liu Chunhua; Zhang Qilin; Gong Shaobo; Nie Lin; Shi Zhongbing

doi:10.11884/HPLPB202638.250317

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Hou Zhipei, Deng Bihe, Chen Chengyuan, et al. Design of windows for multi-scale turbulence collective scattering diagnostic system on HL-3 Tokamak[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250317

Citation:

Hou Zhipei, Deng Bihe, Chen Chengyuan, et al. Design of windows for multi-scale turbulence collective scattering diagnostic system on HL-3 Tokamak[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250317

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Design of windows for multi-scale turbulence collective scattering diagnostic system on HL-3 Tokamak

doi: 10.11884/HPLPB202638.250317

Southwestern Institute of Physics, Chengdu 610225, China

Received Date: 2025-09-29
Accepted Date: 2026-02-02
Rev Recd Date: 2026-02-26

Available Online: 2026-03-12

Abstract

Abstract

Background
The study of multi-scale turbulence and related anomalous transport under high-performance plasma operation remains an important topic in the research of magnetic confinement fusion. The parameter range of plasmas in the tokamak experiment determines that far-infrared laser collective scattering is the optimal diagnostic method for multi-scale turbulence diagnostics.
Purpose
This paper will discuss the overall design parameters of the diagnostic system and provide a detailed introduction to the design of the windows for the multi-scale turbulence collective scattering (MSTCS) diagnostic system on the HL-3 tokamak.
Methods
The laser beam entrance window of the MSTCS diagnostic system is located in the mid-plane port #6 of the HL-3 tokamak, and the scattered light beams exit from the windows in the mid-plane port #12. The design aspects of the windows include the material selection, clear aperture calculation, window thickness design, mechanical design, and surface quality requirements. Several inter-related factors need to be considered in the design process. These include the diagnostic wavenumber range, wavenumber resolution, wavenumber purity of the scattering data, laser beam transmission coefficients, and the requirements for vacuum sealing and safety.
Results
On the basis of these considerations, a corresponding design scheme was formulated. The technical details of the analysis and design process as well as the design results will be presented.
Conclusions
The MSTCS diagnostic system has been successfully installed on HL-3, and preliminary experimental data confirm the vacuum safety and optical performance of the diagnostic windows, thereby validating the overall design.
- collective scattering,
- plasma turbulence,
- far-infrared laser

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References(16)

References

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