A5085218261- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Laser-Plasma Interactions and Diagnostics
- Nuclear reactor physics and engineering
- Plasma Diagnostics and Applications
- Particle accelerators and beam dynamics
- Nuclear Materials and Properties
- Nuclear Physics and Applications
- Laser-induced spectroscopy and plasma
- Semiconductor materials and devices
- Atomic and Molecular Physics
- Silicon and Solar Cell Technologies
- Advanced Data Storage Technologies
- Solar and Space Plasma Dynamics
- Physics of Superconductivity and Magnetism
- High-Energy Particle Collisions Research
- Electrostatic Discharge in Electronics
- Thin-Film Transistor Technologies
- Geomagnetism and Paleomagnetism Studies
- Semiconductor Quantum Structures and Devices
- Advancements in Semiconductor Devices and Circuit Design
- Dust and Plasma Wave Phenomena
- Semiconductor Lasers and Optical Devices
Aalto University
2016-2025
Universidad de Sevilla
2025
Culham Centre for Fusion Energy
2006-2024
Institut de Recherche sur la Fusion par Confinement Magnétique
2024
CEA Cadarache
2024
Culham Science Centre
2006-2024
Max Planck Institute for Plasma Physics
2024
Royal Military Academy
2020
Lawrence Livermore National Laboratory
2002-2018
VTT Technical Research Centre of Finland
2010-2017
Progress, since the ITER Physics Basis publication (ITER Editors et al 1999 Nucl. Fusion 39 2137–2664), in understanding processes that will determine properties of plasma edge and its interaction with material elements is described. Experimental areas where significant progress has taken place are energy transport scrape-off layer (SOL) particular anomalous scaling, particle SOL plays a major role diverted plasmas main-chamber elements, localized mode (ELM) deposition on mechanism for ELM...
A stochastic magnetic boundary, produced by an applied edge resonant perturbation, is used to suppress most large edge-localized modes (ELMs) in high confinement ($H$-mode) plasmas. The resulting $H$ mode displays rapid, small oscillations with a bursty character modulated coherent 130 Hz envelope. transport barrier and core are unaffected the despite threefold drop toroidal rotation. These results demonstrate that boundaries compatible may be attractive for ELM control next-step fusion tokamaks.
This paper reports the successful installation of JET ITER-like wall and realization its technical objectives. It also presents an overview planned experimental programme which has been optimized to exploit new other enhancements in 2011/12.
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...
Metallic mirrors will be used in ITER for optical diagnostics working different spectral ranges. Their properties change with time due to erosion, deposition, and particle implantation. First tests of molybdenum were performed the DIII-D divertor under deposition-dominated conditions. Two sets recessed 2cm below floor private flux region exposed a series identical, lower-single-null, ELMing (featuring edge localized modes) H-mode discharges detached plasma conditions both legs. The first set...
Dust production and accumulation present potential safety operational issues for the ITER. diagnostics can be divided into two groups: of dust on surfaces in plasma. Diagnostics from both groups are employed contemporary tokamaks; new suitable ITER also being developed tested. is likely to occur hidden areas, e.g., between tiles under divertor baffles. A novel electrostatic detector monitoring these regions has been tested at PPPL. In DIII-D tokamak include Mie scattering Nd:YAG lasers,...
Large sub-millisecond heat pulses due to Type-I edge localized modes (ELMs) have been eliminated reproducibly in DIII-D for periods approaching nine energy confinement times (τE) with small dc currents driven a simple magnetic perturbation coil. The current required eliminate all but few isolated ELM impulses during coil pulse is less than 0.4% of plasma current. Based on field line modelling, the fields resonate flux surfaces across most pedestal region (0.9 ⩽ ψN 1.0) when q95 = 3.7 ± 0.2,...
In this paper the manipulation of power deposition on divertor targets at DIII-D by application resonant magnetic perturbations (RMPs) for suppression large type-I edge localized modes (ELMs) is analysed. We discuss modification ELM characteristics RMP applied. It shown that width pattern in ELMy H-mode depends linearly deposited energy, whereas phase discharge those patterns are controlled externally induced perturbation. was also found heat transport due to small, plasma pedestal electron...
The impact of carbon and beryllium/tungsten as plasma-facing components on plasma radiation, divertor power particle fluxes, neutral conditions in the divertors has been assessed JET both experimentally by edge fluid code simulations for plasmas low-confinement mode. In high-recycling studies show a 30% reduction total radiation scrape-off (SOL) layer when replacing (JET-C) with beryllium main chamber tungsten (JET-ILW). Correspondingly, at low-field side (LFS) plate two-fold increase...
In a wide variety of natural and laboratory magnetized plasmas, filaments appear as result interchange instability. These convective structures substantially enhance transport in the direction perpendicular to magnetic field. According filament models, their propagation may follow different regimes depending on parallel closure charge conservation. This is paramount importance fusion high collisionality scrape-off layer trigger regime transition leading strongly enhanced particle fluxes....
The provision of a particle and power exhaust solution which is compatible with first-wall components edge-plasma conditions key area present-day fusion research mandatory for successful operation ITER DEMO. work package plasma-facing (WP PFC) within the European programme complements laboratory experiments, i.e. in linear plasma devices, electron ion beam loading facilities, studies performed toroidally confined magnetic such as JET, ASDEX Upgrade, WEST etc. connection both groups done via...
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...
Based on the dipole model of peptide groups developed in our earlier work [Liwo et al., Prot. Sci., 2, 1697 (1993)], a cumulant expansion average free energy system freely rotating peptide-group dipoles tethered to fixed α-carbon trace is derived. A graphical approach presented find all nonvanishing terms cumulants. In particular, analytical expressions for three- and four-body (correlation) averaged interaction potential united are These similar cooperative forces hydrogen bonding...
Far Scrape-Off Layer (SOL) and near-wall plasma parameters in DIII-D depend strongly on the discharge confinement regime. In L-mode discharges cross-field transport increases with average density flattens far SOL profiles, thus increasing contact low field side (LFS) main chamber wall. H-mode between edge localized modes (ELMs) plasma–wall is weaker than L-mode. During ELM fluxes of particles heat to LFS wall increase transiently above values. Depending conditions, ELMs are responsible for...
A study of three-dimensional (3D) perturbed magnetic field structures and transport for edge localized mode control experiments with resonant perturbations at DIII-D is presented. We focus on ITER-Similar Shape plasmas ITER relevant electron pedestal collisionalities . This performed in comparison results from TEXTOR-Dynamic Ergodic Divertor circular limiter plasmas. For both the structure analyzed vacuum paradigm—superimposing external RMP unperturbed equilibrium. TEXTOR L-mode this...
A low amplitude (δbr∕BT=1 part in 5000) edge resonant magnetic field perturbation with toroidal mode number n=3 and poloidal numbers between 8 15 has been used to suppress most large type I localized modes (ELMs) without degrading core plasma confinement. ELMs have suppressed for periods of up 8.6 energy confinement times when the safety factor q95 is 3.5 4. The are replaced by packets events (possibly II ELMs) small amplitude, narrow radial extent, a higher level density fluctuations,...
The new full-metal ITER-like wall (ILW) at JET was found to have a profound impact on the physics of disruptions. main difference is significantly lower fraction (by up factor 5) energy radiated during disruption process, yielding higher plasma temperatures after thermal quench and thus longer current times. Thus, larger total conducted resulting in heat loads. Active mitigation by means massive gas injection became necessity avoid beryllium melting already moderate levels magnetic (i.e....
A bifurcative step transition from low-density, high-temperature, attached divertor conditions to high-density, low-temperature, detached is experimentally observed in DIII-D tokamak plasmas as density increased. The only the high confinement mode and when $B\ifmmode\times\else\texttimes\fi{}\ensuremath{\nabla}B$ drift directed towards divertor. This work reports for first time a theoretical explanation numerical simulations that qualitatively reproduce this bifurcation its dependence on...
In the recent JET experimental campaigns with new ITER-like wall (JET-ILW), major progress has been achieved in characterization and operation of H-mode regime metallic environments: (i) plasma breakdown at first attempt X-point L-mode recovered a few days operation; (ii) stationary stable type-I ELMy H-modes βN ∼ 1.4 have low high triangularity shape plasmas are showing that their operational domain H = 1 is significantly reduced JET-ILW mainly because need to inject large amount gas (above...
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....
Type I ELMy H-mode operation in JET with the ITER-like Be/W wall (JET-ILW) generally occurs at lower pedestal pressures compared to those full carbon (JET-C). The density is similar but temperature where type ELMs occur reduced and below so-called critical I–type III transition reported JET-C experiments. Furthermore, confinement factor H98(y,2) baseline plasmas JET-ILW low power fractions Ploss/Pthr,08 < 2 (where Ploss (Pin − dW/dt), Pthr,08 L–H threshold from Martin et al 2008 (J. Phys....