A5087538114- Laser-induced spectroscopy and plasma
- Magnetic confinement fusion research
- Atomic and Molecular Physics
- Ionosphere and magnetosphere dynamics
- Plasma Diagnostics and Applications
- Fusion materials and technologies
- Laser-Plasma Interactions and Diagnostics
- Solar and Space Plasma Dynamics
- Nuclear reactor physics and engineering
- Mass Spectrometry Techniques and Applications
- Dust and Plasma Wave Phenomena
- Spectroscopy and Laser Applications
- Fluid Dynamics and Turbulent Flows
- Astrophysics and Star Formation Studies
- Superconducting Materials and Applications
- High-Energy Particle Collisions Research
- Quantum, superfluid, helium dynamics
- Astro and Planetary Science
- Forecasting Techniques and Applications
- Advanced Chemical Physics Studies
- Combustion and flame dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- X-ray Spectroscopy and Fluorescence Analysis
- Astronomical Observations and Instrumentation
- Nuclear Physics and Applications
Centre National de la Recherche Scientifique
2012-2024
Aix-Marseille Université
2012-2024
Physique des interactions ioniques et moléculaires
2008-2023
Royal Military Academy
2020
Forschungszentrum Jülich
2010
Japan Atomic Energy Agency
2008
Institute for Atomic and Molecular Physics
2008
The TCV tokamak is augmenting its unique historical capabilities (strong shaping, strong electron heating) with ion heating, additional heating compatible high densities, and variable divertor geometry, in a multifaceted upgrade program designed to broaden operational range without sacrificing fundamental flexibility. rooted three-pronged approach aimed at ITER support, explorations towards DEMO, research. A 1 MW, tangential neutral beam injector (NBI) was recently installed promptly...
Stark broadening of hydrogen lines in the presence a magnetic field is revisited, with emphasis on role ion component under typical conditions magnetized fusion devices. An impact theory for ions valid at low density $({N}_{e}\ensuremath{\lesssim}{10}^{14}\text{ }{\text{cm}}^{\ensuremath{-}3})$ and taking into account Zeeman degeneracy removal atomic states developed. It shown that widths Lorentz triplet components strongly depend field. The model validated by computer simulation method. For...
The effect of turbulence on the transport neutral species (atom, molecules) in plasmas is investigated. A stochastic model relying a multivariate gamma distribution introduced to describe turbulent fluctuations, and implemented EIRENE. effects fluctuations density ionization source radial profiles are role temperature discussed detail. Calculations with ITER scrape-off layer parameters presented, two distinct regimes respect identified, depending far SOL mean temperature. Finally, influence...
This work addresses the transport of neutral particles (atoms, molecules) in magnetized fusion plasmas, presence density fluctuations with given statistics. The latter are described by a multivariate gamma distribution. geometry is 2D slab and turbulence assumed to be statistically homogeneous. average ionization source, which quantities relevant for integrated simulations diagnostic applications, calculated analytically scattering free case. boundary conditions ratio correlation length mean...
Abstract Artificial Intelligence (AI) and data science techniques are increasingly introduced in physics including plasma where Machine Learning (ML) is applied to emission spectroscopy for parameter determination. Recently, the open-access python-based Sickit-Learn ML platform was used analyze line intensities order infer electron densities temperatures conditions relevant tokamak divertors. In this paper, we discuss application of deep-learning (DL) synthetic spectra magnetic fusion...
Analysis of asymmetric Dα spectra emitted in front a neutralizer plate the Tore-Supra ergodic divertor, M Koubiti, Y Marandet, A Escarguel, H Capes, L Godbert-Mouret, R Stamm, C De Michelis, Guirlet, Mattioli
Abstract The physical model used in the photon transport module of Monte‐Carlo code EIRENE ( www.eirene.de ) is presented. A critical assessment spectral line broadening mechanisms (which give shape photon‐atom reaction rates) and their relevance a simulation carried out (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The impact approximation used in the modelling of Stark profiles is examined when a magnetic field present. Motivated by tokamak plasma spectroscopy, we calculate line shapes and S-matrix elements for first Lyman lines hydrogen with two models proposed retaining simultaneously Zeeman effects limit. An evaluation accuracy approaches made help numerical simulation.
We address a model for atomic population kinetics in fluctuating plasmas. An analytical expression the ensemble-average populations is obtained terms of two statistical functions that can be retrieved experimentally, namely probability density function and autocorrelation plasma fluid fields. This expression, allowing very fast calculations, great interest to thoroughly analyze radiative properties Two limits, where fluctuations are either faster or slower than relaxation time scales,...
Carbon pellets were injected into high-temperature plasmas produced in the Large Helical Device (LHD), a heliotron-type fusion experimental device. Radiation from high-density plasma formed around pellet core, so-called ablation cloud, was observed and its spectrum UV–visible wavelength range obtained. The is found to be dominated by emission lines of CII CIII ions, their level populations are determined measured line intensities. result suggests that LTE (local thermodynamic equilibrium)...
The transport of neutral particles in turbulent plasmas is addressed from the prospect developing coarse-grained models which can be implemented code suites like B2-EIRENE, currently used for designing ITER divertor. statistical properties fluctuations are described by a multivariate Gamma distribution able to retain space and time correlations through proper choice covariance function. We show that scattering free case, relevant molecules impurity atoms, average particle density obeys...
The shape of atomic spectral lines in plasmas contains information on the plasma parameters, and can be used as a diagnostic tool. Under specific conditions, located at edge tokamaks has parameters similar to those magnetic white dwarf stellar atmospheres, which suggests that same line models used. A problem common tokamak dwarfs concerns modeling Stark broadening hydrogen presence an external field related Zeeman effect. In this work, we focus selection issues relevant magnetized plasmas....
Line shape spectroscopy is a valuable tool both for diagnostic purposes, and understanding the basic atomic processes in boundary region of magnetically confined fusion plasmas. We report on present state versatile line model including Stark, Zeeman Doppler broadening an arbitrary emitter divertor or other edge Several examples temperature density diagnostics based use this are presented neutral ionized carbon, hydrogen isotopes. In case Dα line, fitting to experimental spectra involves...
Starting from first principles, we derive for the time a comprehensive formalism allowing to calculate Doppler spectral line shapes emitted in plasmas affected by low-frequency turbulence. The apparent velocity distribution function (VDF) of emitters turbulent plasma, deduced analysis, is expressed terms joint probability density (PDF) fluctuating plasma fields. In case where temperature fluctuations are dominant, use analytic expressions PDF, theoretical predictions VDF. We show that PDFs...
For a given set of plasma parameters, along single series (Lyman, Balmer, etc.) the lines with higher principal quantum number (n) get progressively wider, closer to each other, and start merging for certain critical n. In present work, four different codes (with further options) are used calculate entire Balmer moderate high electron densities. Particular attention is paid relevant physics, such as cutoff criteria, strong penetrating collisions.
A computer simulation technique is applied to the modelling of Balmer line shapes in dense divertor conditions. The spectral profile lines with a high principal quantum number n sensitive Stark broadening and can be used as density diagnostic. In contrast, an analysis shape low or moderate such D α ( = 3), β 4), γ 5) more intricate because effect weaker compete thermal Doppler broadening. We examine this issue address relative contribution effects on first lines. Analyses experimental...
We propose in this paper the use of artificial intelligence, especially deep learning algorithms, for isotopic ratio determination hydrogen–deuterium mixtures. Our approach is based on Balmer-α line emitted by hydrogen and deuterium, but unlike standard method, it does not consist fitting Hα/Dα spectra. Instead, only some basic spectroscopic features such as peak-to-dip wavelength separation, peak-to-peak dip-to-peak intensity ratios Zeeman–Doppler-broadened spectra are used regression...
The influence of low-frequency temperature fluctuations on Doppler line shapes is investigated. It shown that the profile can be strongly narrowed if ion and electron temperatures are correlated. This result shows widely used model retaining only velocity in analysis lines might lead to misleading conclusions about turbulence level.