S. Aleiferis
A5045088255- Magnetic confinement fusion research
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Atomic and Molecular Physics
- Nuclear reactor physics and engineering
- Gyrotron and Vacuum Electronics Research
- Ionosphere and magnetosphere dynamics
- Nuclear Physics and Applications
- High-Energy Particle Collisions Research
- Electrohydrodynamics and Fluid Dynamics
- Diamond and Carbon-based Materials Research
- Laser-induced spectroscopy and plasma
- Metal and Thin Film Mechanics
- Spectroscopy and Laser Applications
- Nuclear Materials and Properties
- Fault Detection and Control Systems
- Plasma Applications and Diagnostics
- Nuclear Engineering Thermal-Hydraulics
- Advanced Chemical Physics Studies
- Electron and X-Ray Spectroscopy Techniques
- Anomaly Detection Techniques and Applications
- Gas Sensing Nanomaterials and Sensors
Culham Centre for Fusion Energy
2022-2024
National Centre of Scientific Research "Demokritos"
2019-2024
Culham Science Centre
2020-2024
United Kingdom Atomic Energy Authority
2023-2024
Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety
2020-2022
Institute of Nuclear and Particle Physics
2022
Centre National de la Recherche Scientifique
2013-2021
Université Grenoble Alpes
2013-2021
Laboratoire de Physique Subatomique et de Cosmologie
2016-2021
University of Patras
2012-2020
Abstract The JET 2019–2020 scientific and technological programme exploited the results of years concerted engineering work, including ITER-like wall (ILW: Be W divertor) installed in 2010, improved diagnostic capabilities now fully available, a major neutral beam injection upgrade providing record power 2019–2020, tested technical procedural preparation for safe operation with tritium. Research along three complementary axes yielded wealth new results. Firstly, plasma delivered scenarios...
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 For the past several years, JET scientific programme (Pamela et al 2007 Fusion Eng. Des . 82 590) has been engaged in a multi-campaign effort, including experiments D, H and T, leading up to 2020 first with 50%/50% D–T mixtures since 1997 ever plasmas ITER mix of plasma-facing component materials. this purpose, concerted physics technology was launched view prepare campaign (DTE2). This paper addresses key elements developed by directly contributing preparation. intense preparation...
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...
Abstract After the second Deuterium–Tritium Campaign (DTE2) in JET tokamak with ITER-Like Wall (ILW) and full tritium campaigns that preceded followed after DTE2, a sequence of fuel recovery methods was applied to promote removal from wall components. The started several days baking main chamber walls at 240 °C 320 °C. Subsequently, superimposed Ion-Cyclotron Conditioning (ICWC) Glow Discharge (GDC) cleaning cycles deuterium. Diverted plasma operation deuterium different strike point...
Success of the UK’s Spherical Tokamak for Energy Production (STEP) programme requires a robust plasma control system. This system has to guide from initiation burning phase, maintain it there, produce desired fusion power duration and then terminate safely. be done in challenging environment with limited sensors without overloading plasma-facing components. The parameters operational regime STEP prototype will very different tokamaks, which are presently operation. During burn,...
The objective of thermonuclear fusion consists producing electricity from the coalescence light nuclei in high temperature plasmas. most promising route to envisages confinement such plasmas with magnetic fields, whose studied configuration is tokamak. Disruptions are catastrophic collapses affecting all tokamak devices and one main potential showstoppers on a commercial reactor. In this work we report how, deploying innovative analysis methods thousands JET experiments covering isotopic...
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 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 This study investigates the dependence of radial electric field (Er) on line-averaged density in JET L-mode plasmas, utilizing Doppler backscattering measurements. Density ramp discharges up to limit are analyzed investigate physical processes that determine edge Er profile. At low densities, profile at midplane exhibits a pronounced peak near scrape-off layer (SOL) and shallow well inside separatrix. As increases, SOL diminishes quickly deepens until Greenwald fraction fGW ≈ 0.8,...
During the past decade multi-dipolar plasmas have been employed for various purposes such as surface treatments in biomedicine, physical and chemical vapour deposition hydrogen storage, applications mechanical engineering. On other hand, due to design operational mode of these plasma sources (i.e., strong permanent magnets electron cyclotron resonance coupling, low working pressure, high density achieved) they are suitable studying fundamental mechanisms involved negative ion used...
Abstract In 2019 the UK launched Spherical Tokamak for Energy Production (STEP) programme to design and build a prototype electricity producing nuclear fusion power plant, aiming start operation around 2040. The plant should lay foundation development of commercial plants. is based on spherical tokamak principle, which opens route high pressure, steady state, operation. While facilitating state operation, introduces some specific plasma control challenges: (i) All current during burn phase...
The potential to use liposomes (LIPs) as a cellular model in order study interactions of cold atmospheric-pressure plasma with cells is herein investigated. Cold formed by dielectric-barrier discharge reactor. Large multilamellar vesicle liposomes, consisted phosphatidylcholine and cholesterol, are prepared the thin film hydration technique, encapsulate small hydrophilic dye, i.e., calcein. plasma-induced release calcein from then used measure liposome membrane integrity and, consequently,...
Abstract Changes in global and edge plasma parameters ( H 98(y,2) , dimensionless collisionality ν * core density peaking, separatrix n e,sep ) with variations the D 2 fueling rate divertor configuration are unified into a single trend when mapped to ⟨ T e,ot ⟩, spatially averaged spectroscopically derived outer target electron temperature. Dedicated JET ITER-like wall (JET-ILW) experiments combination an extended JET-ILW database of unseeded low-triangularity H-mode plasmas spanning wide...
Abstract A sequence of fuel recovery methods was tested in JET, equipped with the ITER-like beryllium main chamber wall and tungsten divertor, to reduce plasma deuterium concentration less than 1% preparation for operation tritium. This also a key activity regard refining clean-up strategy be implemented at end 2nd DT campaign JET (DTE2) assess tools that are envisaged mitigate tritium inventory build-up ITER. The began 4 days baking 320 °C, followed by further which Ion Cyclotron Wall...
Abstract Analysis of the divertor edge localized mode (ELM) electron temperature at a uniquely high temporal resolution (10 −5 s) was reported JET tokamak (Guillemaut et al 2018 Nucl. Fusion 58 066006). By collecting probe data obtained during many dozens ELMs, conditional-average (CAV) technique yields surprisingly low peak temperatures, far below pedestal ones (70%–99% reduction!) which we, however, question. This result interpreted through collisional free-streaming kinetic model by...
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>...
Benchmarking and validation are prerequisites for using simulation codes as predictive tools. In this work, we have developed a Global Model Negative Hydrogen Ion Source (GMNHIS) performed benchmarking of the GMNHIS against another independently code, Enhanced Vibrational Kinetic (GEVKM). This is first study to present quite comprehensive test kind models negative hydrogen ion sources (NHIS), excellent agreements been achieved collisional energy loss per electron-ion pair created, electron...
Measurements of the ion currents to and plasma conditions at low-field side (LFS) divertor target plate in low-confinement mode plasmas JET ITER-like wall materials configuration show that core density required detach LFS is independent hydrogenic species protium, deuterium tritium, a 40 %/60 % deuterium–tritium mixture. This observation applies with strike line connected horizontal part chosen because its superior diagnostic coverage. The finding operational status cryogenic pump. electron...
In this paper we present optimized actuator trajectories, evolving in time and space, of non-inductive ramp-up scenarios for the Spherical Tokamak Energy Production (STEP). These trajectories are computed by solving a non-linear, multi-objective, constrained, finite-time optimal control problem. A method unique to STEP studies that provides an alternative existing trajectory search strategies which rely on manually adjusting reach desired state. To navigate non-linear parameter space is...