<abstract xmlns="http://www.w3.org/1999/xhtml"><p> A high-resolution spectroscopic system for the measurements of the CIII triplet at 465 nm was installed at the COMPASS tokamak. The Doppler broadening and shift of the measured spectral lines are used to calculate the edge ion temperature and poloidal plasma rotation. At first, the spectroscopic system based on two-grating spectrometer and the calibration procedure is described. The signal processing including detection and removal of spiky features in the signal caused by hard X-rays based on the difference in the behaviour of Savitzky-Golay and median filters is explained. The detection and position estimation of individual spectral lines based on the continuous wavelet transform is shown. The method of fitting of Gaussians using the orthogonal distance regression and estimation of the error of estimation of the rotation velocity and ion temperature is described. At the end, conclusions about the performance of the spectroscopic system and its shortcomings based on summary of results calculated from 2033 processed spectral lines measured in 61 shots are drawn and the possible enhancements are suggested.</p></abstract>

A high-resolution spectroscopic system for the measurements of the CIII triplet at 465 nm was installed at the COMPASS tokamak. The Doppler broadening and shift of the measured spectral lines are used to calculate the edge ion temperature and poloidal plasma rotation. At first, the spectroscopic system based on two-grating spectrometer and the calibration procedure is described. The signal processing including detection and removal of spiky features in the signal caused by hard X-rays based on the difference in the behaviour of Savitzky-Golay and median filters is explained. The detection and position estimation of individual spectral lines based on the continuous wavelet transform is shown. The method of fitting of Gaussians using the orthogonal distance regression and estimation of the error of estimation of the rotation velocity and ion temperature is described. At the end, conclusions about the performance of the spectroscopic system and its shortcomings based on summary of results calculated from 2033 processed spectral lines measured in 61 shots are drawn and the possible enhancements are suggested.

Calculation of edge ion temperature and poloidal rotation velocity from carbon III triplet measurements on the COMPASS tokamak

Institute of Plasma Physics ASCR, v.v.i., Faculty of Mathematics and Physics, Charles University in Prague, Za Slovankou 3, 18200, Praha 8, Czechia

Institute of Plasma Physics ASCR, v.v.i., Faculty of Mathematics and Physics, Charles University in Prague, Za Slovankou 3, 18200 Praha 8, Czechia

Instituto de Plasmas e Fusao Nuclear, Lisboa,

Nukleonika

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

A high-resolution spectroscopic system for the measurements of the CIII triplet at 465 nm was installed at the COMPASS tokamak. The Doppler broadening and...

Calculation of edge ion temperature and poloidal rotation velocity from carbon III triplet measurements on the COMPASS tokamak

Article Category: Proceedings of the Summer School of Plasma Diagnostics Phdiafusion 2015: “Soft X-Ray Diagnostics for Fusion Plasma” Bezmiechowa, Poland, 16-20 June 2015

Published Online: Oct 26, 2016

Page range: 443 - 451

Received: Sep 03, 2015

Accepted: Apr 11, 2016

DOI: https://doi.org/10.1515/nuka-2016-0073

Keywords
high-resolution spectroscopy, spectra processing, peak detection, line detection, line fitting, poloidal plasma rotation, ion temperature

© by Matěj Tomeš

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Calculation of edge ion temperature and poloidal rotation velocity from carbon III triplet measurements on the COMPASS tokamak

Article Category: Proceedings of the Summer School of Plasma Diagnostics Phdiafusion 2015: “Soft X-Ray Diagnostics for Fusion Plasma” Bezmiechowa, Poland, 16-20 June 2015

Published Online: Oct 26, 2016

Page range: 443 - 451

Received: Sep 03, 2015

Accepted: Apr 11, 2016

DOI: https://doi.org/10.1515/nuka-2016-0073

Keywordshigh-resolution spectroscopy, spectra processing, peak detection, line detection, line fitting, poloidal plasma rotation, ion temperature

© by Matěj Tomeš

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
high-resolution spectroscopy, spectra processing, peak detection, line detection, line fitting, poloidal plasma rotation, ion temperature