Abstract
A bolometer/soft x-ray diagnostic based on modular absolute extreme ultraviolet photodiodes has been built to obtain the local emission profile of a poloidal cross section in Sino-UNIted Spherical Tokamak (SUNIST). The system consists of seven photodiode arrays of 112 channels located around the low field side of a poloidal cross section. All arrays are mounted into 81 × 36 × 33mm3 modules, which could be installed flexibly on the wall of the vacuum vessel. Tungsten shields with adjustable pinholes restrict the radiation flux. Compact flexible printed circuits with multilayer copper polygon poured on both sides are designed to transmit signals with electronic noise, which is reduced to less than 1/10 before. A two-stage transimpedance amplifier array of 700 kHz bandwidth is fixed on the atmosphere side of a vacuum electrical feedthrough and is powered by battery packs. A synchronized switch shuts down the circuit to reduce the heat production and increase the battery life. A line-integrated radiation emission profile with 2cm spatial resolution and temporal resolution up to 2 µs is obtained, and the local emission profile of SUNIST is reconstructed with the help of a newly developed tomography scheme for movable detector modules.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
