A5060188810- Magnetic confinement fusion research
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Nuclear reactor physics and engineering
- Nuclear Physics and Applications
- Solar and Space Plasma Dynamics
- High-Energy Particle Collisions Research
- Electrostatic Discharge in Electronics
- Gyrotron and Vacuum Electronics Research
- Chaos control and synchronization
- Meteorological Phenomena and Simulations
- Quantum, superfluid, helium dynamics
- Adipose Tissue and Metabolism
- Nuclear physics research studies
- thermodynamics and calorimetric analyses
- Model Reduction and Neural Networks
- Time Series Analysis and Forecasting
- Complex Systems and Time Series Analysis
- Atomic and Molecular Physics
- Nuclear Materials and Properties
- Nuclear Engineering Thermal-Hydraulics
Max Planck Institute for Plasma Physics
2014-2025
Culham Science Centre
2015-2024
United Kingdom Atomic Energy Authority
2020-2024
Royal Military Academy
2012-2024
Culham Centre for Fusion Energy
2013-2023
European Steel Association
2016-2023
European Commission
2021
Uppsala University
2020
Laboratoire de Physique des Plasmas
2007-2020
National Institute for Laser Plasma and Radiation Physics
2020
Abstract The quasi-continuous exhaust (QCE) regime is a that naturally type-I ELM-free. It combines the high density at plasma edge needed for power with normalised energy confinement typical H-mode operation. In QCE large-scale ELMs are avoided and high-frequent, low-amplitude filaments present leading to name-giving transport of particles energy.
This contribution reports first time was successfully achieved in JET metal wall. More so, it demonstrated recent deuterium-tritium...
Experiments were carried out in the JET tokamak to determine critical ion temperature inverse gradient length (R/LTi=R|nablaTi|/Ti) for onset of modes and stiffness Ti profiles with respect deviations from value. Threshold have been compared linear nonlinear predictions gyrokinetic code GS2. Plasmas higher values toroidal rotation show a significant increase R/LTi, which is found be mainly due decrease level. This finding has implications on extrapolation future machines present day results...
New transport experiments on JET indicate that ion stiffness mitigation in the core of a rotating plasma, as described by Mantica et al. [Phys. Rev. Lett. 102, 175002 (2009)] results from combined effect high rotational shear and low magnetic shear. The observations have important implications for understanding improved confinement advanced tokamak scenarios. Simulations using quasilinear fluid gyrofluid models show features mitigation, while nonlinear gyrokinetic simulations do not....
The dependence of plasma transport and confinement on the main hydrogenic ion isotope mass is fundamental importance for understanding turbulent and, therefore, accurate extrapolations from present tokamak experiments, which typically use a single hydrogen isotope, to burning plasmas such as ITER, will operate in deuterium–tritium mixtures. Knowledge properties edge barrier formation species critical view initial, low-activation phase ITER operations or helium its implications subsequent...
A comparison of the L–H power threshold (Pthr) in JET with all carbon, JET-C, and beryllium/tungsten wall (the ITER-like choice), JET-ILW, has been carried out experiments slow input ramps matched plasma shapes, divertor configuration IP/BT pairs. The low density dependence threshold, namely an increase below a minimum ne,min, which was first observed MkII-GB C subsequently not current MkII-HD geometry, is again JET-ILW. At densities above Pthr reduced by ∼30%, ∼40% when radiation from bulk...
Abstract In JET deuterium-tritium (D-T) plasmas, the fusion power is produced through thermonuclear reactions and between thermal ions fast particles generated by neutral beam injection (NBI) heating or accelerated electromagnetic wave in ion cyclotron range of frequencies (ICRFs). To complement experiments with 50/50 D/T mixtures maximizing reactivity, a scenario dominant non-thermal reactivity has been developed successfully demonstrated during second campaign DTE2, as it was predicted to...
Abstract The JET hybrid scenario has been developed from low plasma current carbon wall discharges to the record-breaking Deuterium-Tritium plasmas obtained in 2021 with ITER-like Be/W wall. development started pure Deuterium refinement of current, and toroidal magnetic field choices succeeded solving heat load challenges arising 37 MW injected power ITER like environment, keeping radiation edge core controlled, avoiding MHD instabilities reaching high neutron rates. have re-run Tritium...
The W-transport in the core plasma of JET is investigated experimentally by deriving W-concentration profiles from modelling signals soft x-ray cameras. For case pure neutral beam heating W accumulates (r/a < 0.3) approaching W-concentrations 10−3 between sawtooth crashes, which flatten W-profile to a concentration about 3 × 10−5. When central Ion cyclotron resonant additionally applied decays phases that exhibit changed mode activity, while also electron temperature increases and density...
The scan of ion cyclotron resonant heating (ICRH) power has been used to systematically study the pump out effect central electron on impurities such as Ni and Mo in H-mode low collisionality discharges JET. transport parameters have measured by introducing a transient perturbation their densities via laser blow off technique. Without ICRH density profiles are typically peaked. application induces plasma centre (at normalized poloidal flux ρ = 0.2) an outward drift approximately proportional...
Abstract Ion cyclotron resonance frequency (ICRF) heating has been an essential component in the development of high power H-mode scenarios Jet European Torus ITER-like wall (JET-ILW). The ICRF performance was improved by enhancing antenna-plasma coupling with dedicated main chamber gas injection, including preliminary minimization RF-induced plasma-wall interactions, while RF where optimized for core impurity screening terms ion position and minority hydrogen concentration. impact on...
This paper reports the progress made at JET-ILW on integrating requirements of reference ITER baseline scenario with normalized confinement factor 1, a pressure 1.8 together partially detached divertor whilst maintaining these conditions over many energy times. The 2.5 MA high triangularity ELMy H-modes are studied two different configurations D-gas injection and nitrogen seeding. power load reduction N seeding is reported. relationship between an increase in pedestal investigated....
The JET exploitation plan foresees D–T operations in 2020 (DTE2). With respect to the first campaign 1997 (DTE1), when was equipped with a carbon wall, experiments will be conducted presence of beryllium–tungsten ITER-like wall and benefit from an extended improved set diagnostics higher additional heating power (32 MW neutral beam injection + 8 ion cyclotron resonance heating). There are several challenges presented by new wall: general deterioration pedestal confinement; risk heavy...
The evolution of the JET high performance hybrid scenario, including central accumulation tungsten (W) impurity, is reproduced with predictive multi-channel integrated modelling over multiple confinement times using first-principle based core transport models.8 channels ( , ) are modelled predictively, self-consistent sources, radiation and magnetic equilibrium, yielding a system non-linearities: This can reproduce observed radiative temperature collapse after several times.W transported...
This paper summarizes the physical principles behind novel three-ion scenarios using radio frequency waves in ion cyclotron range of frequencies (ICRF). We discuss how to transform mode conversion electron heating into a new flexible ICRF technique for and fast-ion generation multi-ion species plasmas. The theoretical section provides practical recipes selecting plasma composition realize scenarios, including two equivalent possibilities choice resonant absorbers that have been identified....
Abstract In this work the onset of tearing modes in termination phase plasma pulses on JET is investigated. It shown that broadening or shrinking current density profile, as a consequence core hollowing an edge cooling electron temperature strongly increases probability destabilizing 2/1 mode also absence external trigger (e.g. sawtooth crash). Two parameters are defined to highlight changes shape profile can lead MHD instabilities and empirical stability diagram introduced into space two...
Abstract In the paper we present an overview of interpretive modelling a database JET-ILW 2021 D-T discharges using TRANSP code. The main aim is to assess our capability computationally reproducing fusion performance various plasma scenarios different external heating and mixtures, understand driving mechanisms. We find that simulations confirm general power-law relationship between increasing power output, which supported by absolutely calibrated neutron yield measurements. A comparison...
In JET, lower hybrid (LH) and ion cyclotron resonance frequency (ICRF) wave absorption in the scrape-off layer can lead to enhanced heat fluxes on some plasma facing components (PFCs). Experiments have been carried out characterize these loads order to: (i) prepare JET operation with Be wall which has a reduced power handling capability as compared carbon (ii) better understand physics driving phenomena propose solutions for next generation systems reduce them. When using ICRF, hot spots are...
The spectral broadening of characteristic γ-ray emission peaks from the reaction (12)C((3)He,pγ)(14)N was measured in D((3)He) plasmas JET tokamak with ion cyclotron resonance heating tuned to fundamental harmonic (3)He. Intensities and detailed shapes were successfully reproduced using a physics model combining kinetics reacting ions description nuclear differential cross sections for populating L1-L8 (14)N excitation levels yielding observed emission. results provide paradigm, which...
To consolidate International Thermonuclear Experimental Reactor (ITER) design choices and prepare for its operation, Joint European Torus (JET) has implemented ITER's plasma facing materials, namely, Be the main wall W in divertor. In addition, protection systems, diagnostics, vertical stability control were upgraded heating capability of neutral beams was increased to over 30 MW. First results confirm expected benefits limitations all metal components (PFCs) but also yield understanding...
Dedicated experiments to generate energetic D ions and fusion-born alpha particles were performed at the Joint European Torus (JET) with ITER-like wall (ILW). Using 3-ion radio frequency (RF) heating scenario, deuterium from neutral beam injection (NBI) accelerated in core of mixed plasmas higher energies ion cyclotron resonance (ICRF) waves, turn leading a core-localized source particles. The fast-ion distribution RF-accelerated D-NBI was controlled by varying ICRF NBI power ( 4–6 MW, 3–20...
Abstract We present an overview of results from a series L–H transition experiments undertaken at JET since the installation ITER-like-wall (JET-ILW), with beryllium wall tiles and tungsten divertor. Tritium, helium deuterium plasmas have been investigated. Initial in tritium show ohmic transitions low density power threshold for ( P LH ) is lower than ones densities, while we still lack contrasted data to provide scaling high densities. In there notable shift which minimum <?CDATA...
Abstract The recent deuterium–tritium campaign in JET-ILW (DTE2) has provided a unique opportunity to study the isotope dependence of L-H power threshold an ITER-like wall environment (Be and W divertor). Here we present results from dedicated transition experiments at JET-ILW, documenting tritium plasmas, comparing them with matching deuterium hydrogen datasets. From earlier it is known that as plasma isotopic composition changes deuterium, through varying deuterium/hydrogen concentrations,...
Abstract JET experiments using the fuel mixture envisaged for fusion power plants, deuterium and tritium (D–T), provide a unique opportunity to validate existing D–T prediction capabilities in support of future device design operation preparation. The 2021 experimental campaign has achieved powers sustained over 5 s ITER-relevant conditions i.e. with baseline or hybrid scenario full metallic wall. In preparation campaign, extensive predictive modelling was carried out several assumptions...