M. Aradi

55566164300

Publications - 7

Atomic Beam Probe Synthetic Diagnostic in the COMPASS Tokamak and Its Application in Fusion Plasmas

M. Berta P. Hacek D. Réfy M. Aradi G. I. Pokol J. Krbec O. Asztalos Shimpei Futatani S. Zoletnik

Publication Name: Fusion Science and Technology

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The atomic beam probe (ABP) is a beam diagnostic concept that opens opportunities in plasma edge measurements due to the sensitivity of the magnetic field and the high temporal resolution. The first ABP has been installed and is operating on the COMPASS tokamak. A new numerical toolset, which is the subject of this paper, was required to model the diagnostic to accurately detect the alkali beam. For further development and understanding of the diagnostic, this tool had to be designed to simulate different magnetic field configurations in a performance-efficient manner. The TAIGA synthetic diagnostic (TAIGA-SD), which was implemented with a massively parallel trajectory solver core that runs on graphic cards to support experiments, provides a better understanding of measurements and has opened opportunities for future applications. This paper presents the model concept with relevant physical processes and necessary simplifications. The submodules implemented or integrated into the synthetic diagnostic are explained and described, and their scopes of validity are highlighted. This includes the integration of RENATE-OD for the primary ionization radial distribution for lithium beams, as well as the implementation and verification of a combined electron impact and charge exchange ionization module for other alkaline beams, which is a new atomic physics solver. Calculations were performed to investigate the relation between magnetic field, electron density, and temperature perturbations. Further simulations were run to estimate beam attenuation due to secondary ionization. The utilization of the ABP synthetic diagnostic is demonstrated by comparing it with the measurements.

Open Access: Yes

DOI: 10.1080/15361055.2025.2511540

Plasma edge current fluctuation measurements during the ELM cycle with the atomic beam probe at COMPASS

M. Berta G. Anda D. Dunai P. Hacek D. Réfy M. Aradi J. Krbec S. Zoletnik A. Bencze

Publication Name: 46th Eps Conference on Plasma Physics Eps 2019

Publication Date: 2019-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

No description provided

Open Access: Yes

DOI: DOI not available

Development of an ion beam detector for the atomic beam probe diagnostic

M. Berta G. Anda D. Dunai P. Hacek D. Réfy M. Aradi J. Krbec R. Pánek S. Zoletnik A. Bencze V. Weinzettl J. Stockel

Publication Name: Review of Scientific Instruments

Publication Date: 2018-11-01

Volume: 89

Issue: 11

Page Range: Unknown

Description:

The atomic beam probe diagnostic concept aims at measuring the edge magnetic field and through that edge current distribution in fusion plasmas by observing trajectories of an ion beam stemming from a diagnostic neutral beam. The diagnostic potentially has microsecond scale time resolution and can thus prove to be a powerful option to study fast changes in the edge plasma. A test detector has been installed on the COMPASS tokamak as an extension of the existing lithium beam diagnostic system. It employs a relatively simple concept of an array of conductive detection plates measuring the incident ion current, which is then amplified and converted to a voltage signal. The aim of the test detector is to experimentally examine the idea of the diagnostic and provide background data for design and installation of a final detector. Also, a numerical code based on the CUDA parallel computing platform has been developed for modeling lithium ion trajectories in the given COMPASS plasma discharges. We present the developments of the detector design and test measurements of the diagnostic performed both in a laboratory beam system and on the COMPASS tokamak.

Open Access: Yes

DOI: 10.1063/1.5044529

Advanced neutral alkali beam diagnostics for applications in fusion research (invited)

D. Réfy B. Tál G. Petravich G. I. Pokol M. Vécsei G. Anda D. Dunai M. Aradi O. Asztalos S. Bató G. Demeter S. Hegedus P. Hacek M. Berta A. Bencze T. Krizsanóczi M. Lampert G. H. Hu D. Nagy J. Németh M. Otte S. Zoletnik

Publication Name: Review of Scientific Instruments

Publication Date: 2018-10-01

Volume: 89

Issue: 10

Page Range: Unknown

Description:

Diagnosing the density profile at the edge of high temperature fusion plasmas by an accelerated lithium beam is a known technique since decades. By knowledge of the relevant atomic physics rate coefficients, the plasma electron density profile can be calculated from the relatively calibrated light profile along the beam. Several additional possibilities have already been demonstrated: Charge Exchange Resonance Spectroscopy (CXRS) for ion temperature/flow and Zeeman polarimetry for edge plasma current; therefore the Li-beam diagnostic offers a wealth of information at the plasma edge. The weaknesses of the method are the relatively faint light signal, background light, and technical difficulties of the beam injector which usually seriously limit the applicability. In this talk, we present systematic developments in alkali-beam diagnostics (Li, Na) for the injector and the observation system and detectors which resulted in strongly increased capabilities. Advanced systems have been built, and microsecond scale density profile, turbulence, and zonal flow measurement have been demonstrated. A novel edge current measurement technique has also been designed, and components have been tested with potential microsecond-scale time resolution. Additional possibilities of these advanced systems for spectral measurements (CXRS and various Zeeman schemes) are also discussed.

Open Access: Yes

DOI: 10.1063/1.5039309

Atomic Beam Probe diagnostic for plasma edge current measurements at COMPASS

M. Berta G. Anda D. Dunai P. Hacek D. Réfy M. Aradi M. Lampert J. Krbec M. Palánkai S. Hegedus B. Leskó J. Kádi D. Nagy R. Pánek S. Zoletnik A. Bencze V. Weinzettl

Publication Name: 45th Eps Conference on Plasma Physics Eps 2018

Publication Date: 2018-01-01

Volume: 2018-July

Issue: Unknown

Page Range: 1028-1031

Description:

No description provided

Open Access: Yes

DOI: DOI not available

Development of atomic beam probe for tokamaks

M. Berta G. Anda I. G. Kiss J. Havlicek S. Tulipán P. Hacek M. Aradi Cs Buday G. Veres S. Zoletnik A. Bencze

Publication Name: Fusion Engineering and Design

Publication Date: 2013-11-01

Volume: 88

Issue: 11

Page Range: 2875-2880

Description:

The concept and development of a new detection method for light alkali ions stemming from diagnostic beams installed on medium size tokamak is described. The method allows us the simultaneous measurement of plasma density fluctuations and fast variations in poloidal magnetic field, therefore one can infer the fast changes in edge plasma current. The concept has been worked out and the whole design process has been done at Wigner RCP. The test detector with appropriate mechanics and electronics is already installed on COMPASS tokamak. General ion trajectory calculation code (ABPIons) has also been developed. Detailed calculations show the possibility of reconstruction of edge plasma current density profile changes with high temporal resolution, and the possibility of density profile reconstruction with better spatial resolution compared to standard Li-BES measurement, this is important for pedestal studies. © 2013 Elsevier B.V.

Open Access: Yes

DOI: 10.1016/j.fusengdes.2013.05.064

Concept of an atomic beam probe diagnostic on COMPASS tokamak

M. Berta G. Anda D. Dunai M. Aradi G. Veres S. Zoletnik A. Bencze

Publication Name: 36th Eps Conference on Plasma Physics 2009 Eps 2009 Europhysics Conference Abstracts

Publication Date: 2009-12-01

Volume: 33 E2

Issue: Unknown

Page Range: 1399-1402

Description:

No description provided

Open Access: Yes

DOI: DOI not available