Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions
The present study focuses on the development of a diagnostic system for measuring radiated power and core soft X-ray intensity emissions with the goal of detecting a broad spectrum of photon energies emitted from the central plasma region of the DEMO tokamak. The principal objective of the diagnosti...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-05-01
|
| Series: | Sensors |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1424-8220/25/10/3162 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850256366817509376 |
|---|---|
| author | Tomasz Czarski Maryna Chernyshova Katarzyna Mikszuta-Michalik Karol Malinowski |
| author_facet | Tomasz Czarski Maryna Chernyshova Katarzyna Mikszuta-Michalik Karol Malinowski |
| author_sort | Tomasz Czarski |
| collection | DOAJ |
| description | The present study focuses on the development of a diagnostic system for measuring radiated power and core soft X-ray intensity emissions with the goal of detecting a broad spectrum of photon energies emitted from the central plasma region of the DEMO tokamak. The principal objective of the diagnostic apparatus is to deliver a comprehensive characterization of the radiation emitted by the plasma, with a particular focus on estimating the radiated power from the core region. This measurement is essential for determining and monitoring the power crossing the separatrix, which is a critical parameter controlling overall plasma performance. Since diagnostics rely on line-integrated measurements, the application of tomographic reconstruction techniques is necessary to extract spatially resolved information on core plasma radiation. This contribution presents the development of numerical algorithms addressing the problem of radiation tomography reconstruction. A robust and computationally efficient method is proposed for reconstructing the spatial distribution of plasma radiated power, with a view toward enabling real-time applications. The reconstruction methodology is based on a linear model formulated using a set of predefined basis functions, which define the radiation distribution within a specified plasma cross-section. In the initial stages of emissivity reconstruction in tokamak plasmas, it is typically assumed that the radiation distribution is dependent on magnetic flux surfaces. As a baseline approach, the plasma radiative properties are considered invariant along these surfaces and can thus be represented as one-dimensional profiles parameterized by the poloidal magnetic flux. Within this framework, the reconstruction method employs an approximation model utilizing three sets of basis functions: (i) polynomial splines, as well as Gaussian functions with (ii) sigma parameters and (iii) position parameters. The performance of the proposed method was evaluated using two synthetic radiated power emission phantoms, developed for the DEMO plasma scenario. The results indicate that the method is effective under the specified conditions. |
| format | Article |
| id | doaj-art-629ec8eee75a443a8fa8dd12d6298a8b |
| institution | OA Journals |
| issn | 1424-8220 |
| language | English |
| publishDate | 2025-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj-art-629ec8eee75a443a8fa8dd12d6298a8b2025-08-20T01:56:39ZengMDPI AGSensors1424-82202025-05-012510316210.3390/s25103162Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis FunctionsTomasz Czarski0Maryna Chernyshova1Katarzyna Mikszuta-Michalik2Karol Malinowski3Institute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw, PolandNational Centre for Nuclear Research, Andrzeja Sołtana 7, 05-400 Otwock, PolandInstitute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw, PolandInstitute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw, PolandThe present study focuses on the development of a diagnostic system for measuring radiated power and core soft X-ray intensity emissions with the goal of detecting a broad spectrum of photon energies emitted from the central plasma region of the DEMO tokamak. The principal objective of the diagnostic apparatus is to deliver a comprehensive characterization of the radiation emitted by the plasma, with a particular focus on estimating the radiated power from the core region. This measurement is essential for determining and monitoring the power crossing the separatrix, which is a critical parameter controlling overall plasma performance. Since diagnostics rely on line-integrated measurements, the application of tomographic reconstruction techniques is necessary to extract spatially resolved information on core plasma radiation. This contribution presents the development of numerical algorithms addressing the problem of radiation tomography reconstruction. A robust and computationally efficient method is proposed for reconstructing the spatial distribution of plasma radiated power, with a view toward enabling real-time applications. The reconstruction methodology is based on a linear model formulated using a set of predefined basis functions, which define the radiation distribution within a specified plasma cross-section. In the initial stages of emissivity reconstruction in tokamak plasmas, it is typically assumed that the radiation distribution is dependent on magnetic flux surfaces. As a baseline approach, the plasma radiative properties are considered invariant along these surfaces and can thus be represented as one-dimensional profiles parameterized by the poloidal magnetic flux. Within this framework, the reconstruction method employs an approximation model utilizing three sets of basis functions: (i) polynomial splines, as well as Gaussian functions with (ii) sigma parameters and (iii) position parameters. The performance of the proposed method was evaluated using two synthetic radiated power emission phantoms, developed for the DEMO plasma scenario. The results indicate that the method is effective under the specified conditions.https://www.mdpi.com/1424-8220/25/10/3162plasma diagnosticsX-ray tomographybasis functions approach |
| spellingShingle | Tomasz Czarski Maryna Chernyshova Katarzyna Mikszuta-Michalik Karol Malinowski Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions Sensors plasma diagnostics X-ray tomography basis functions approach |
| title | Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions |
| title_full | Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions |
| title_fullStr | Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions |
| title_full_unstemmed | Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions |
| title_short | Reconstruction of Tokamak Plasma Emissivity Distribution by Approximation with Basis Functions |
| title_sort | reconstruction of tokamak plasma emissivity distribution by approximation with basis functions |
| topic | plasma diagnostics X-ray tomography basis functions approach |
| url | https://www.mdpi.com/1424-8220/25/10/3162 |
| work_keys_str_mv | AT tomaszczarski reconstructionoftokamakplasmaemissivitydistributionbyapproximationwithbasisfunctions AT marynachernyshova reconstructionoftokamakplasmaemissivitydistributionbyapproximationwithbasisfunctions AT katarzynamikszutamichalik reconstructionoftokamakplasmaemissivitydistributionbyapproximationwithbasisfunctions AT karolmalinowski reconstructionoftokamakplasmaemissivitydistributionbyapproximationwithbasisfunctions |