A5060209411- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Nuclear reactor physics and engineering
- Laser-Plasma Interactions and Diagnostics
- Solar and Space Plasma Dynamics
- Gas Dynamics and Kinetic Theory
- Nuclear Materials and Properties
- Quantum Computing Algorithms and Architecture
- Silicon Carbide Semiconductor Technologies
- Antenna Design and Analysis
- Gyrotron and Vacuum Electronics Research
- Quantum Information and Cryptography
- Scientific Measurement and Uncertainty Evaluation
- Advanced Antenna and Metasurface Technologies
- Advanced Sensor Technologies Research
- Nuclear Physics and Applications
- Metamaterials and Metasurfaces Applications
- Atomic and Subatomic Physics Research
- Dust and Plasma Wave Phenomena
- Plasma and Flow Control in Aerodynamics
- Advancements in Semiconductor Devices and Circuit Design
LINKS Foundation
2021-2025
Tokamak Energy (United Kingdom)
2024
Max Planck Institute for Plasma Physics
2010-2019
Max Planck Society
2009-2018
Max Planck Institute for Plasma Physics - Greifswald
2011
Culham Science Centre
2011
École Polytechnique Fédérale de Lausanne
2001-2008
Max Planck Innovation
2007
Plasma Technology (United States)
2001
Massachusetts Institute of Technology
2001
A multi-machine database for the H-mode scrape-off layer power fall-off length, λq in JET, DIII-D, ASDEX Upgrade, C-Mod, NSTX and MAST has been assembled under auspices of International Tokamak Physics Activity. Regression inside finds that most important scaling parameter is poloidal magnetic field (or equivalently plasma current), with decreasing linearly increasing Bpol. For conventional aspect ratio tokamaks, regression , yielding λq,ITER ≅ 1 mm baseline inductive burning scenario at Ip...
Experimental measurements of the SOL power decay length (λ(q)) estimated from analysis fully attached divertor heat load profiles two tokamaks, JET and ASDEX Upgrade, are presented. Data was measured by means infrared thermography. An empirical scaling reveals parametric dependency λ(q) in mm = 0.73B(T)(-0.78)q(cyl)(1.2)P(SOL)(0.1)R(geo)(0), where B(T)(T) describes toroidal magnetic field, q(cyl) cylindrical safety factor, P(SOL)(MW) crossing separatrix R(geo)(m) major radius device. A...
Parametric scalings of the intrinsic (spontaneous, with no external momentum input) toroidal rotation observed on a large number tokamaks have been combined an eye towards revealing underlying mechanism(s) and extrapolation to future devices. The velocity has found increase plasma stored energy or pressure in JET, Alcator C-Mod, Tore Supra, DIII-D, JT-60U TCV, decrease increasing current some these cases. Use dimensionless parameters led roughly unified scaling MA ∝ βN, although variety Mach...
In this paper, a new experimental classification of divertor detachment in ASDEX Upgrade is presented. For purpose, series ohmic and L-mode density ramp discharges at different heating powers, magnetic field directions plasma species were carried out. the first time electron volume occurrence recombination measured by means spectroscopy. It shown that not continuously evolving process but rather undergoes three distinct states while characteristics inner outer are strongly coupled. Before...
An overview of the H-mode threshold power in ASDEX Upgrade which addresses impact tungsten versus graphite wall, dependences upon plasma current and density, as well influence ion mass is given.Results on H-L back transition are also presented.Dedicated L-H studies with electron heating at low enable a complete separation channels, reveal that heat flux key parameter physics mechanism through main pressure gradient itself contribution to radial electric field induced flow shearing edge.The...
Diagnostic tools for understanding the edge plasma behavior in fusion devices are essential. The main focus of present work is to infra-red (IR) diagnostics installed on Tokamak Energy’s spherical tokamak (ST40) and IR thermographic inversion tool, Functional Analysis Heat Flux (FAHF). FAHF designed multi-2D inversions within divertor tiles using finite difference method an explicit time stepping scheme. ST40’s re-entrant endoscope allows acquisition data with highest available effective...
Bulk plasma toroidal rotation is observed to invert spontaneously from counter cocurrent direction in TCV (Tokamak \`a Configuration Variable) Ohmically heated discharges, low confinement mode, without momentum input. The inversion occurs high current when the electron density exceeds a well-defined threshold. transition between two rotational regimes has been studied by means of ramps. results provide evidence change balance nondiffusive fluxes core an external drive.
In 2008, experiments have been carried out in ASDEX Upgrade to compare Hmode power threshold and confinement time helium deuterium.A scan magnetic field a wide density variation indicate that the two gases is very similar.The dependence of exhibits clear minimum.Confinement about 30% lower than deuterium, mainly due reduction ion caused by Z=2 helium.
Predicting intrinsic plasma rotation and its shear, which often help stabilize instabilities affecting performance, is important for prospective fusion grade devices. Although in ITER-like scenarios has been extrapolated from measured experimental data, little understood about the underlying mechanisms governing either generation or dissipation of momentum a tokamak plasma. This paper reports on studies toroidal poloidal charge exchange spectroscopy using low power diagnostic beam TCV...
Power exhaust is one of the major challenges for development a fusion power plant.Predictions based upon multi machine database give scrapeoff layer fall-off length λ q ≤ 1 mm large devices such as ITER.The deposition profile on target broadened in divertor by heat transport perpendicular to magnetic field lines.This broadening described spreading S. Hence both and S need be understood order estimate expected load future devices.For investigation L-Mode discharges with stable conditions...
The first toroidal rotation measurements in TCV ohmic L-mode plasmas with no external momentum injection are presented. velocity profile of the fully stripped carbon species is measured by active Charge eXchange Recombination Spectroscopy a temporal resolution typically 90 ms and spatial 2.5 cm, about 1/10 plasma radius. observed order deuterium diamagnetic drift up to 1/5 thermal velocity. It directed opposite current electron direction. reverses when reversing current. angular flat, or...
Theoretical approaches to low-frequency magnetized turbulence in collisionless and weakly collisional astrophysical plasmas are reviewed. The proper starting point for an analytical description of these is kinetic theory, not fluid equations. anisotropy the used systematically derive a series reduced models. Above ion gyroscale, it shown rigourously that Alfven waves decouple from electron-density magnetic-field-strength fluctuations satisfy Reduced MHD density field-strength (slow entropy...
For the design and operation of large fusion devices a detailed understanding power exhaust processes is necessary.This paper will give an overview current research on divertor load mechanisms.The results shown are obtained in JET with ITER like wall ASDEX Upgrade tungsten coated plasma facing components.The challenges infrared thermography bulk presented.For steady state heat load, fall-off length λ q JET-ILW compared to empirical scaling found carbon components.A first attempt scale...
The upstream separatrix electron density is an important interface parameter for core performance and divertor power exhaust. It has been measured in ASDEX Upgrade H-mode discharges by means of Thomson scattering using a self-consistent estimate the temperature under assumption Spitzer–Härm conduction. Its dependence on various plasma parameters tested different conditions H-mode. leading determining ne,sep was found to be neutral pressure, which can considered as engineering since it...
In this article we present the development of a new diagnostic capable determining electron density in divertor volume ASDEX Upgrade (AUG). It is based on spectroscopic measurement Stark broadening Balmer lines. work two approaches calculating broadening, i.e. unified theory and model microfield method, are compared. will be shown that both yield similar results case lines with high upper principal quantum numbers n. addition, for typical AUG parameters influence Zeeman splitting n found to...
ASDEX Upgrade became a full tungsten experiment in 2007 by coating its graphite plasma facing components with tungsten. In 2013 redesigned solid divertor, Div-III, was installed and came into operation 2014. The redesign of the outer divertor geometry provided opportunity to increase pumping efficiency lower increasing gap between vessel. parallel, by-pass cryo-pump region allowing adapting speed required edge density.
Hypersonic flight regime is conventionally defined for Mach larger than 5; in these conditions, the flying object becomes enveloped a plasma. This plasma densest thin surface layers, but typical situations of interest it impacts electromagnetic wave propagation an electrically large volume. We address this problem with hybrid approach. employ Equivalence Theorem to separate inhomogeneous region from surrounding free space via equivalent (Huygens) surface, and Eikonal approximation Maxwell...