Fast density reconstruction of Li-BES signal on the COMPASS tokamak

0498188 - ÚFP 2019 RIV US eng J - Journal Article
Krbec, Jaroslav - Háček, Pavel - Berta, M. - Seidl, Jakub - Hron, Martin - Pánek, Radomír
Fast density reconstruction of Li-BES signal on the COMPASS tokamak.
Review of Scientific Instruments. Roč. 89, č. 11 (2018), č. článku 113504. ISSN 0034-6748. E-ISSN 1089-7623
R&D Projects: GA ČR(CZ) GA16-25074S; GA MŠMT(CZ) 8D15001; GA MŠMT(CZ) LM2015045
Institutional support: RVO:61389021
Keywords : density profile reconstruction * BES * Li-beam * COMPASS tokamak
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 1.587, year: 2018
https://aip.scitation.org/doi/10.1063/1.5049894

This article describes a fast and automatic reconstruction of the edge plasma electron density from the radiation of energetic Li atoms of the diagnostic beam on the COMPASS tokamak. Radiation is detected by using a CCD camera and by using an avalanche photo-diode system with a temporal resolution of 20 ms and 2 mu s, respectively. Both systems are equipped with a 670.8 nm optical filter which corresponds to the lithium 1s(2)2s(1)-1s(2)2p(1) transition. A theoretical model and a data processing procedure of a raw signal to obtain the density profile are described. The reconstruction algorithm provides the absolutely calibrated electron density profiles together with the measurement error estimated from relatively calibrated light profiles, the implementation is performed in Python. Time demanding operations of the code were optimized to provide reconstruction of a single profile within less than 10 ms which makes the code applicable for processing of a large amount of data. Thanks to this calculation speed, it is possible to reconstruct electron density profiles between two consecutive shots on the COMPASS tokamak with 2 mu s time resolution.
Permanent Link: http://hdl.handle.net/11104/0290584