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International Thermonuclear Experimental Reactor (ITER) Radial X-ray Camera (RXC) is installed in the equatorial port #12 (middle drawer) to measure the poloidal profile of the plasma x-ray emission with high spatial and temporal resolution. According to the irradiation test results with Co-60 gamma ray source, Cf-252 neutron source and the result in Deuterium - Tritium (DT) accelerator neutron irradiation experiment for RXC electronics before, the weak parts of the circuit have been improved by radiation resistance design such as using radiation-hard power chip and optimizing the Field Programmable Gate Array (FPGA) code. Other factors related to radiation, such as easiness of maintenance, compact electronics structure and remote state monitoring are also considered in the design. The performance of the electronics and chassis has been preliminarily verified in Experimental Advanced Superconducting Tokamak (EAST) experiments showing resistance to interference from discharge environment. Besides, the irradiation resistance of electronics was investigated in high fluence neutron irradiation experiment in fission reactor, where the detector, pre-amplifier, mid-amplifier and cables under test received the accumulated neutron fluence over 9.89×1013n/cm-2 (1MeV equivalent), and the quality of output signal was monitored in real time. It’s found after the experiment that the pre-amplifier worked well, while the detector and mid-amplifier were partly damaged.

A high spatial and temporal resolution soft x-ray (SXR) imaging diagnostic has been installed in EAST for the study of magnetohydrodynamics activities and core high-Z impurity transport. Up to 122 lines of sight view the poloidal plasma from three directions (two up-down symmetrical horizontal arrays and one vertical array), which renders the diagnostic able to provide detailed tomographic reconstructions under various conditions. Fourier-Bessel method based on flux coordinates was employed for 2-D SXR tomographic reconstruction. Examples of several events measured by SXR diagnostic in EAST are shown, namely the crash patterns of sawtooth, periodical burst of edge localized modes, and the transport of high-Z intrinsic impurities.