Počet záznamů: 1  

Optimization of soft X-ray tomography on the COMPASS tokamak

  1. 1. 0464277 - UFP-V 2017 RIV PL eng J - Článek v odborném periodiku
    Imríšek, Martin - Mlynář, Jan - Löffelmann, Viktor - Weinzettl, Vladimír - Odstrčil, T. - Odstrčil, M. - Tomeš, Matěj
    Optimization of soft X-ray tomography on the COMPASS tokamak.
    Nukleonika. Roč. 61, č. 4 (2016), s. 403-408 ISSN 0029-5922.
    [Summer School of Plasma Diagnostics PhDiaFusion 2015: “Soft X-ray Diagnostics for Fusion Plasma”. Bezmiechowa, 16.06.2015-20.06.2015]
    Grant CEP: GA MŠk(CZ) LM2011021; GA MŠk LG14002; GA MŠk(CZ) 8D15001
    GRANT EU: European Commission(XE) 633053 - EUROfusion
    Institucionální podpora: RVO:61389021
    Klíčová slova: soft X-ray * tomography * Tikhonov regularization * tokamak
    Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
    Impakt faktor: 0.760, rok: 2016

    The COMPASS tokamak is equipped with the soft X-ray (SXR) diagnostic system based on silicon photodiode arrays shielded by a thin beryllium foil. The diagnostic is composed of two pinhole cameras having 35 channels each and one vertical pinhole camera with 20 channels, which was installed recently to improve tomographic inversions. Lines of sight of the SXR detectors cover almost complete poloidal cross section of the COMPASS vessel with a spatial resolution of 1–2 cm and temporal resolution of about 3 micro s. Local emissivity is reconstructed via Tikhonov regularization constrained by minimum Fisher information that provides
    reliable and robust solution despite limited number of projections and ill-conditionality of this task. Improved border conditions and numerical differentiation matrices suppressing artifacts in reconstructed radiation were implemented in the code. Furthermore, a fast algorithm eliminating iterative processes was developed, and it is foreseen to be tested in real-time plasma control.
    Trvalý link: http://hdl.handle.net/11104/0263423