Development of a Thomson Scattering Diagnostic System on EAST

Abstract

A multipulse and multipoint Nd:YAG (neodymium-yttrium aluminum garnet) laser Thomson scattering diagnostic system was developed on EAST to obtain more accurate electron temperature Te and electron density ne profiles. In this paper, the optical system, the VME (versa module eurocard)-based real-time computer system for laser control, data acquisition, analysis and calibration are discussed in detail. Furthermore, a developed data processing method is presented.

Kinetic equilibrium reconstruction for the NBI- and ICRH-heated H-mode plasma on EAST tokamak

“…where the impurity temperature is assumed to be the same as the main ion temperature T. i In the experiment, T e is measured by the Thomson scattering (TS) [31,32], n e is measured by the TS, the polarimeter-interferometer (POINT) [33]. With the assumption of a single impurity (usually carbon), n i and n z are deduced from the measured Z eff and n e according to the quasi-neutrality condition.…”

Design and development of a synchronized operation control system for Thomson scattering diagnostic on J-TEXT

“…Thomson scattering (TS) is a widely used diagnostic system to measure the electron temperature ( ) T e and electron density ( ) n e and to obtain their profiles [1,2]. A laser TS system has been designed or constructed for many tokamaks such as DIII-D, JT60-U, KSTAR, EAST, HL-2A, and ITER, of which the last one is considered the largest tokamak in the world [3][4][5][6][7][8]. Currently, at Joint Texas Experimental Tokamak (J-TEXT), T e and n e are obtained using an electron cyclotron emission (ECE) diagnostic and polarimeter-interferometer diagnostic, respectively [9,10].…”

Analysis method for Thomson scattering diagnostics in GAMMA 10/PDX

“…Thomson scattering (TS) diagnostics is one of the most useful methods for measuring electron temperature, T e , and density, n e , in fusion plasmas. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] For the tandem mirror GAMMA 10/PDX, we developed TS diagnostics for T e and n e measurements for single laser and plasma shots. 6 The value of n e (∼2 × 10 18 m −3 ) in the GAMMA 10/PDX plasma is typically lower than that in other fusion plasmas.…”

“…1,2,4 Some TS systems use high-speed analog-todigital converters or oscilloscopes to obtain the raw signal waveforms. [6][7][8][9][10][11] The output signals of the polychromators in a TS system are normally fitted to a Gaussian function in order to obtain the single-pass TS signal intensities. [7][8][9][10][11] TS data processing methods for raw TS signals with high-timeresolution data acquisition systems have been developed for electron temperature and density measurements, e.g., Monte-Carlo simulation for analyzing TS signals, 12 maximumlikelihood fitting method for TS fitting data, 13 and non-Gaussian pulse shape fitting method.…”