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A prototype real-time (RT) Thomson scattering system was tested in a KSTAR Thomson scattering diagnostic system [1]. For this RT-Thomson system, 155 channels of 5 GS/s digitizer were operated (31 polychromators, each has 5 signal channels used in the KSTAR Thomson scattering system). The 5 Giga Sampling / second (GS/s) digitizer restored the pulsed Thomson scattering signals, and these acquired digital signals were fitted using a pulse function and Fast Fourier Transformation (FFT) method to remove noise with high speed on the TS signals [2]. The pulse fitting parameters (pulse height, rising time, falling time and peak position) were applied to calculate plasma parameters like the electron temperature (T e). To reduce the T e calculation time, a neural-network (NN) method was introduced using graphic processor unit (GPU) calculations. These plasma parameters were transmitted to the KSTAR plasma control system (PCS)using a reflective memory (RFM) card. The delay time of this RT-Thomson before transfer to the RFM card measured less than 7 ms for a T e calculation of 31 positions, and the transfer time from the RFM card to the PCS was 6.8 ms. Therefore, at 80.31% of KSTAR long pulse plasma shot # 32,763 (84.15 s), the end-to-end treatment time was less than 50 ms. The uniqueness of this paper is that it uses 5GS/s digitizer, Fast Fourier Transformation FFT fitting method, and neural- network (NN) analysis system, and finally succeeds in transferring Te profile data to the KSTAR PCS system in real- time (80.31% within 50 ms delay) using RFM cards for KSTAR long pulse plasma (84.15 s) for the first time. [ABSTRACT FROM AUTHOR]

To measure the effective ion charge Z eff profile, most plasma machines are equipped with a bremsstrahlung measurement system as a filter-scope diagnostic device. In Korean Superconducting Tokamak Advanced Research (KSTAR) machine, a new type of bremsstrahlung measurement system, called hybrid-type polychromator system, was developed and tested at a single position during the 10th KSTAR plasma campaign [1] . The main idea of this hybrid-type polychromator system is to combine a polychromator system, which can measure the Thomson scattering signal, with a bremsstrahlung signal measurement system. The advantages of this hybrid-type polychromator system include the reduction of diagnostic vacuum windows in the Tokamak or Stellarator, and the measurement of the Z eff parameter with electron temperature ( T e ) and electron density ( n e ) at a same position. In this study, we improve last year's hybrid-type polychromator system. A major improvement is the change in the structure of the optical system. This allows measuring the bremsstrahlung signals more clearly, and four hybrid-type polychromators were equipped to measure the Z eff profile preliminarily. In this paper, we explain the structure of the hybrid-type polychromator and the system's measurement results. [ABSTRACT FROM AUTHOR]