A5037463444- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Ionosphere and magnetosphere dynamics
- Nuclear reactor physics and engineering
- Particle accelerators and beam dynamics
- Solar and Space Plasma Dynamics
- Plasma Diagnostics and Applications
- Laser-induced spectroscopy and plasma
- High-Energy Particle Collisions Research
- Magneto-Optical Properties and Applications
- Astronomical Observations and Instrumentation
- Theoretical and Computational Physics
- Characterization and Applications of Magnetic Nanoparticles
- Computational Fluid Dynamics and Aerodynamics
- Magnetic properties of thin films
- Nuclear Materials and Properties
- Atomic and Molecular Physics
- Seismic Waves and Analysis
- Geomagnetism and Paleomagnetism Studies
- Atomic and Subatomic Physics Research
- Optical Systems and Laser Technology
- Metallic Glasses and Amorphous Alloys
- Nuclear Physics and Applications
Culham Science Centre
2015-2024
Culham Centre for Fusion Energy
2010-2024
United Kingdom Atomic Energy Authority
2009-2024
Royal Military Academy
2020
Australian National University
2010
Imperial College London
2009-2010
Ludwig-Maximilians-Universität München
2010
Queen's University Belfast
2009
CEA Cadarache
2009
Université Côte d'Azur
2009
JET underwent a transformation from full carbon-dominated tokamak to fully metallic device with beryllium in the main chamber and tungsten divertor. This material combination is foreseen for activated phase of ITER. The ITER-Like Wall (ILW) experiment at shall demonstrate plasma compatibility walls reduction fuel retention. We report on set experiments (Ip = 2.0 MA, Bt 2.0–2.4 T, δ 0.2–0.4) different confinement conditions global gas balance analysis demonstrating strong long-term retention...
Abstract In 2021 JET exploited its unique capabilities to operate with T and D–T fuel an ITER-like Be/W wall (JET-ILW). This second major campaign (DTE2), after DTE1 in 1997, represented the culmination of a series enhancements—new fusion diagnostics, new injection capabilities, refurbishment plant, increased auxiliary heating, in-vessel calibration 14 MeV neutron yield monitors—as well as significant advances plasma theory modelling community. DTE2 was complemented by sequence isotope...
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...
Disruptions are a major operational concern for next generation tokamaks, including ITER.They may generate excessive heat loads on plasma facing components, large electromagnetic forces in the machine structures and several MA of multi-MeV runaway electrons.A more complete understanding processes methods to suppress them is necessary ensure safe reliable operation future tokamaks.Runaway electrons were studied at JET-ILW showing that their dependencies (accelerating electric field, avalanche...
A new technique has been developed to produce plasmas with improved confinement relative the H98,y2 scaling law (ITER Physics Expert Groups on Confinement and Transport Modelling Database ITER Basics Editors EDA 1999 Nucl. Fusion 39 2175) JET tokamak. In mid-size tokamaks ASDEX upgrade DIII-D heating during current formation is used a flat q-profile minimum close 1. On this leads q-profiles similar q but opposite other not an state. By changing method utilizing faster ramp temporary higher...
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...
Real-time simultaneous control of several radially distributed magnetic and kinetic plasma parameters is being investigated on JET, in view developing integrated advanced tokamak scenarios. This paper describes the new model-based profile controller which has been implemented during 2006–2007 experimental campaigns. The aims to use combination heating current drive (H&CD) systems—and optionally poloidal field (PF) system—in an optimal way regulate evolution parameter profiles such as...
In tokamak experiments, equilibrium reconstruction codes are used to calculate the location of last closed flux surface, map diagnostic information, and derive important properties like current density safety factor. At JET, code EFIT is automatically executed after each discharge. For speed robustness, intershot based on magnetic probe measurements only. As a consequence, profiles factor can be wrong for variety plasma scenarios. Internal pitch angle as measured with motional stark effect,...
Experiments on JET with a carbon-fibre composite wall have explored the reduction of steady-state power load in an ELMy H-mode scenario at high Greenwald fraction ∼0.8, constant and close to L H transition. This paper reports systematic study due effect fuelling combination seeding over wide range pedestal density ((4–8) × 1019 m−3) detailed documentation divertor, main plasma conditions, as well comparative two extrinsic impurity nitrogen neon. It also impact overall behaviour, possible...
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 This paper reports the first experiment carried out in deuterium–tritium addressing integration of a radiative divertor for heat-load control with good confinement. Neon seeding was time D–T plasma as part second campaign JET its Be/W wall environment. The technical difficulties linked to re-ionisation heat load are reported T and D–T. compares impact neon on plasmas their D counterpart detachment, localisation radiation, scrape-off profiles, pedestal structure, edge localised modes global
Abstract The pre-thermal quench (pre-TQ) dynamics of a pure deuterium ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mi mathvariant="normal">D</mml:mi> </mml:mrow> <mml:mn>2</mml:mn> </mml:msub> </mml:math> ) shattered pellet injection (SPI) into <mml:mn>3</mml:mn> <mml:mstyle scriptlevel="0"/> <mml:mi>MA</mml:mi> / <mml:mn>7</mml:mn> <mml:mi>MJ</mml:mi> JET H-mode plasma is studied via 3D non-linear MHD modelling with the JOREK code....
A new pellet injection system was installed at JET designed for both fuelling and ELM pacing. The purpose of the pacing section to validate as a suitable tool mitigation in ITER. Pellet confirmed large size scale JET. dynamics triggered ELMs investigated with respect their spontaneous counterparts. Triggered show features also typical several operational regimes. Since none these regimes unsettled by pellets this is strong hint compatibility other plasma control tools. Observations modelling...
Abstract L to H transition studies at JET have revealed an n = 0, m 1 magnetic oscillation starting immediately the (called M-mode for brevity). While is present a weak ELM-less H-mode regime obtained, with clear increase of density and electron temperature pedestal. It intermediate state between H-mode. In ICRH heated plasmas or low NBI mode pedestal can remain steady (with small oscillations) duration heating phase, order 10 s more. The axisymmetric has period ~0.5–2 ms, poloidal number 1:...
Abstract Experimental trends in thermal plasma partial recombination resulting from massive <?CDATA ${{\text{D}}_2}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mtext>D</mml:mtext> </mml:mrow> <mml:mn>2</mml:mn> </mml:msub> </mml:math> injection into high-Z (Ar) containing runaway electron (RE) plateaus DIII-D and JET are studied for the purpose of achieving sufficiently low density ( ${n_{\text{e}}} \approx {10^{18}}{{\text{m}}^{...
We report the identification of a localized current structure inside JET plasma. It is field-aligned closed helical ribbon, carrying in same direction as background profile (cocurrent), rotating toroidally with ion velocity (corotating). appears to be located at flat spot plasma pressure profile, top pedestal. The spontaneously low density, high rotation plasmas, and can last up 1.4 s, time comparable local resistive time. considerably delays appearance first edge mode.Received 23 November...
The former all-carbon wall on JET has been replaced with beryllium in the main torus and tungsten divertor to mimic surface materials envisaged for ITER. Comparisons are presented between type I H-mode characteristics each design by examining respective scans over deuterium fuelling impurity seeding, required ameliorate exhaust loads both at full capability Attention is focused upon a common high-triangularity, single-null configuration 2.5 MA, q95 ≈ 3.5 yielding most robust all-C...
In this paper, we present the work in implementation of a new calibration for JET real-time polarimeter based on complex amplitude ratio technique and self-validation mechanism data. This allowed easy integration polarimetry measurements into plasma density control (gas feedback control) as well machine protection systems (neutral beam injection heating safety interlocks). The addition was used successfully during 2014 Campaign is envisaged that will operate routinely from 2015 campaign...
Abstract 3D non-linear magnetohydrodynamic simulations of a disruption triggered by massive injection argon gas in JET are performed with the JOREK code. The key role thermal drive m = 2, n 1 tearing mode (i.e. from helical cooling inside island) process is highlighted varying amplitude and position source across simulations, also during simulation. In cases where this persists spite development magnetic stochasticity, which favoured moving an ad hoc way plasma edge into 2/1 island at some...
Abstract The required heating power, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mi>P</mml:mi> <mml:mi>LH</mml:mi> </mml:mrow> </mml:msub> </mml:math> , to access the high confinement regime (H-mode) in tritium containing plasmas is investigated JET with ITER-like wall at a toroidal magnetic field of <mml:mi>B</mml:mi> <mml:mi>t</mml:mi> <mml:mo>=</mml:mo> <mml:mn>1.8</mml:mn> T and plasma current <mml:mi>I</mml:mi>...
The far-infrared diagnostic provides essential internal measurements of the plasma density and magnetic field topology (q-profile via Faraday rotation angle) in real-time. capabilities have recently been extended a number key areas. Fast interferometer data, with 10 μs time resolution, new MATLAB code allowed improved analysis evolution profiles during fast events such as vertical displacements, edge localized mode, pellet fuelling, disruptions. Using polarimeter real-time, calibration...
The paper deals with JET polarimeter measurements and in particular it presents a study of the Faraday rotation angle, which is used as constraint equilibrium codes. This angle can be calculated by means rigorous numerical solution Stokes equations. A detailed comparison calculations carried out time traces measurements, inside limited dataset representative discharges: general, found that Cotton–Mouton phase shift represented to To obtain this agreement for rotation, magnetic surfaces must...
Electron temperature and density profiles consistent with JET high resolution Thomson scattering (HRTS) far infrared (FIR) interferometer data are inferred by a Bayesian joint model using Gaussian processes. Forward models predicting diagnostic including instrument effects such as optics electronics developed independently for both systems in the Minerva framework, combined one model. The full posterior distribution of electron profiles, hyperparameters processes calibration factor is...