A5026530251- Magnetic confinement fusion research
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Nuclear reactor physics and engineering
- Plasma Diagnostics and Applications
- Solar and Space Plasma Dynamics
- Nuclear Physics and Applications
- Laser-induced spectroscopy and plasma
- High-pressure geophysics and materials
- Atomic and Molecular Physics
- Magnetic properties of thin films
- Dust and Plasma Wave Phenomena
- Astrophysics and Star Formation Studies
- Advancements in Semiconductor Devices and Circuit Design
- Magnetic Field Sensors Techniques
- Astrophysical Phenomena and Observations
- Impact of Light on Environment and Health
- Nuclear Materials and Properties
- Aerodynamics and Fluid Dynamics Research
- Silicon and Solar Cell Technologies
- Traffic control and management
- Quantum Chromodynamics and Particle Interactions
Max Planck Institute for Plasma Physics
2021-2025
Czech Academy of Sciences, Institute of Plasma Physics
2024
Massachusetts Institute of Technology
2017-2022
Plasma Technology (United States)
2017-2021
Fusion Academy
2017-2021
Fusion (United States)
2017-2021
General Atomics (United States)
2019
Princeton Plasma Physics Laboratory
2019
Imperial College London
2017
The SPARC tokamak is a critical next step towards commercial fusion energy. designed as high-field ( $B_0 = 12.2$ T), compact $R_0 1.85$ m, $a 0.57$ m), superconducting, D-T with the goal of producing gain $Q>2$ from magnetically confined plasma for first time. Currently under design, will continue path Alcator series tokamaks, utilizing new magnets based on rare earth barium copper oxide high-temperature superconductors to achieve high performance in device. achievable conservative...
Abstract Progress in physics understanding and theoretical model development of plasma transport confinement (TC) the ITPA TC Topical Group since publication ITER Physics Basis (IPB) document (Doyle et al 2007 Nucl. Fusion 47 S18) was summarized focusing on contributions to burning prediction control. This paper provides a general streamlined overview advances that were mainly led by joint experiments activities for last 15 years (see JEX/JA table appendix). starts with scientific strategy...
SPARC is designed to be a high-field, medium-size tokamak aimed at achieving net energy gain with ion cyclotron range-of-frequencies (ICRF) as its primary auxiliary heating mechanism. Empirical predictions conservative physics indicate that baseline plasmas would reach $Q\approx 11$ , which well above mission objective of $Q>2$ . To build confidence will successful, physics-based integrated modelling has also been performed. The TRANSP code coupled the theory-based trapped gyro-Landau...
Diverted discharges at negative triangularity on the DIII-D tokamak sustain normalized confinement and pressure levels typical of standard H-mode scenarios (H98y2 ≃ 1, βN 3) without developing an edge pedestal, despite auxiliary power far exceeding L → H threshold expected from conventional scaling laws. The degradation is substantially weaker than ITER-89P scaling, resulting in a factor that improves with increasing power. absence pedestal beneficial several ways, such as eliminating need...
Experimental conditions obtained on the DIII-D tokamak in ITER Similar Shape (ISS) have been compared extensively with nonlinear gyrokinetic simulation using CGYRO code [Candy et al., J. Comput. Phys. 324, 73–93 (2016)] comparisons spanning ion and electron heat fluxes, impurity particle transport, turbulent fluctuation levels characteristics. Bayesian optimization techniques [Rodriguez-Fernandez Nucl. Fusion 62(7), 076036 (2022)], combined gyrokinetics, used to obtain simultaneously Qi, Qe,...
Abstract The plasma and neutral density dynamics after an edge localized mode are investigated utilized to infer the transport coefficients for pedestal. Lyman-Alpha Measurement Apparatus (LLAMA) diagnostic provides sub-millisecond profile measurements of ionization shows significant poloidal asymmetries in both. Exploiting absolute calibration LLAMA allows quantitative comparison electron main ion profiles determined by charge-exchange recombination, Thomson scattering interferometry....
A long-standing enigma in plasma transport has been resolved by modeling of cold-pulse experiments conducted on the Alcator C-Mod tokamak. Controlled edge cooling fusion plasmas triggers core electron heating time scales faster than an energy confinement time, which long interpreted as strong evidence nonlocal transport. This Letter shows that steady-state profiles, rise and disappearance at higher density measured these are successfully captured a recent local quasilinear turbulent model,...
Laser blow-off injections of aluminum and tungsten have been performed on the DIII-D tokamak to investigate variation impurity transport in a set dedicated ion electron heating scans with fixed value external torque. The particle is quantified via Bayesian inference method, which, constrained by combination charge exchange recombination spectroscopy, soft X-ray measurements, VUV spectroscopy provides detailed uncertainty quantification coefficients. Contrasting discharge phases dominant...
Abstract In recent years, negative triangularity (NT) has emerged as a potential high-confinement L-mode reactor solution. this work, detachment is investigated using core density ramps in lower single null Ohmic plasmas across wide range of upper, lower, and average (the mean upper triangularity: δ ) the TCV tokamak. It universally found that more difficult to access for NT shaping. The outer divertor leg discharges with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"...
Abstract We present a novel framework for quantifying radial impurity transport in the pedestal of ASDEX Upgrade (AUG) discharges. Our method is based on charge-exchange recombination spectroscopy (CXRS) measurements line radiation from multiple charge states, each along radially distributed line-of-sight array steady-state plasmas. Inverse inference diffusive-convective solver Aurora combined with synthetic diagnostic enables us to separate diffusive and convective contributions derive...
We report detailed laboratory observations of the structure a reconnection current sheet in two-fluid plasma regime with guide magnetic field. observe and quantitatively analyze quadrupolar electron pressure variation ion-diffusion region, as originally predicted by extended magnetohydrodynamics simulations. The projection gradient parallel to field contributes significantly balancing electric field, resulting cross-field jets layer are diamagnetic origin. These results demonstrate how...
We present a fully Bayesian approach for the inference of radial profiles impurity transport coefficients and compare its results to neoclassical, gyrofluid gyrokinetic modeling. Using nested sampling, (BITE) framework can handle complex parameter spaces with multiple possible solutions, offering great advantages in interpretative power reliability respect previously demonstrated methods. BITE employs forward model based on pySTRAHL package, built success well-known STRAHL code (Dux 2003...
Abstract Tokamak operation at negative triangularity has been shown to offer high energy confinement without the typical disadvantages of edge pedestals (Marinoni et al 2021 Nucl. Fusion 61 116010). In this paper, we examine impurity transport in DIII-D diverted experiments. Analysis charge exchange recombination spectroscopy reveals flat or hollow carbon density profiles core, and times consistently shorter than times. Bayesian inferences coefficients based on laser blow-off injections...
Abstract The paper presents experimental and modelling results of a comparison negative (NT) positive (PT) triangularity ASDEX Upgrade (AUG) discharges using the plasma shapes presently foreseen in DTT tokamak, under construction Italy. This work is part broader effort investigation to understand whether good properties observed NT scenarios DIII-D TCV may be extrapolated device more generally DEMO future operations. have shown practical gain running these AUG plasmas with only ECRH mixed...
Abstract Experimental measurements of plasma and neutral profiles across the pedestal are used in conjunction with 2D edge modeling to examine stiffness Alcator C-Mod H-mode plasmas. Enhanced D α experiments on observed degradation loss confinement below a critical value net power crossing separatrix, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mi>P</mml:mi> <mml:mi>net</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo>...
Understanding transport in magnetically confined plasmas is critical for developing predictive models future devices such as ITER. Thanks to recent progress simulation and theory, along with enhanced computational power better diagnostic systems, direct quantitative comparisons between experimental results possible. However, validating using additional constraints accounting uncertainties still remains a formidable task. In this work, new optimization framework developed address the issue of...
Cold pulses are introduced in Ohmic DIII-D tokamak plasmas via injection of impurities with a laser blow-off system, revealing for the first time this machine quick increase core electron temperature shortly after edge cold-pulse at low collisionality. The experimental results consistent predict-first simulations heat transport enabled by Trapped Gyro-Landau-Fluid model. Measurements density evolution during propagation high resolution profile reflectometer. reveals pulse from to core, which...
We present Aurora, an open-source package for particle transport, neutrals and radiation modeling in magnetic confinement fusion plasmas.Aurora's modern multi-language interface enables simulations of 1.5D impurity transport within high-performance computing frameworks, particularly the inference coefficients.A user-friendly Python library allows simple interaction with atomic rates from Atomic Data Structure database as well other sources.This a range predictions, both power balance...
The turbulence and transport expected in the SPARC tokamak Primary Reference Discharge (PRD) [P. Rodriguez-Fernandez et al., J. Plasma Phys. 86, 865860503 (2020)] have been investigated with gyrokinetic code CGYRO [J. Candy Comput. 324, 73–93 (2016)]. Linear nonlinear simulations that focus on ion (kθρs&lt;1.0) electron-scale (kθρs&gt;1.0) were used to probe nature of resulting fusion core. It is found PRD, temperature gradient (ITG) dominate over most profile some potential trapped...
Abstract Experiments, gyrokinetic simulations and transport predictions were performed to investigate if a negative triangularity (NT) L-mode option for the Divertor Tokamak Test (DTT) full-power scenario would perform similarly positive (PT) H-mode reference scenario, avoiding harmful edge localized modes (ELMs). The show that beneficial effect of NT coming from edge/scrape-off layer (SOL) region <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow>...
Perturbative transport experiments in magnetically confined plasmas have shown, for more than 20 years, that the injection of cold pulses at plasma edge can trigger increase core temperature. Predictive heat simulations with trapped gyro Landau fluid (TGLF) quasilinear model demonstrate temperature some regimes, and lack thereof other be explained by a change dominant linear micro-instability Alcator C-Mod. The effect density current on pulse are well captured TGLF, including relative...
Abstract An efficient removal of He ash by active pumping in future fusion devices is necessary to avoid fuel dilution and not degrade the core confinement properties. Therefore, a deep understanding underlying physics mechanisms mandatory. Helium exhaust has been experimentally investigated at ASDEX Upgrade tokamak. This an ideal test environment, thanks ITER-like divertor geometry, extensive diagnostics coverage presence plasma-facing components made tungsten. The efficiency, characterized...
We present experimental inferences of cross-field impurity transport coefficients for Alcator C-Mod plasmas using a novel forward model the entire Ca K-alpha spectrum, including satellite lines within spectral range, to compare high-resolution X-ray Imaging Crystal Spectroscopy (XICS). These measurements are complemented by Extreme Ultra-Violet (EUV) spectroscopy that constrains closer edge. Using new atomic data sets both XICS and EUV analysis has enabled consideration line ratios across...