A5070418598- Plasma Diagnostics and Applications
- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Solar and Space Plasma Dynamics
- Atomic and Molecular Physics
- Fusion materials and technologies
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Computer Graphics and Visualization Techniques
- Laser Design and Applications
- Semiconductor Quantum Structures and Devices
- Electromagnetic Simulation and Numerical Methods
- Silicon Carbide Semiconductor Technologies
- Photocathodes and Microchannel Plates
- Electromagnetic Launch and Propulsion Technology
- Computational Geometry and Mesh Generation
- Plasma Applications and Diagnostics
- Scientific Research and Discoveries
- Blood groups and transfusion
- Lightning and Electromagnetic Phenomena
- Cellular Automata and Applications
- Pulsed Power Technology Applications
- Dust and Plasma Wave Phenomena
Czech Academy of Sciences, Institute of Plasma Physics
2018-2021
Czech Technical University in Prague
2000-2018
Tesla Engineering (United Kingdom)
1986
TESLA (Czechia)
1986
The role of the COMPASS tokamak in research generation, confinement and losses runaway electron (RE) population is presented. Recently, two major groups experiments aimed at improved understanding control REs have been pursued. First, effects massive gas injection ( Ar/Ne particles) impurity seeding were studied systematically. observed phenomena include generation post-disruption RE beam current conversion from plasma to RE. Zero loop voltage was implemented order study decay simplified...
This paper presents two scenarios used for generation of a runaway electron (RE) beam in the COMPASS tokamak with focus on decay phase and control beam. The first scenario consists massive gas injection argon into current ramp-up phase, leading to disruption accompanied by plateau generation. In second scenario, smaller amount is order isolate RE from high-temperature plasma. performances radial vertical position feedback were experimentally studied analysed. role energy stability seems be...
Abstract COMPASS addressed several physical processes that may explain the behaviour of important phenomena. This paper presents results related to main fields research obtained in recent two years, including studies turbulence, L–H transition, plasma material interaction, runaway electron, and disruption physics: Tomographic reconstruction edge/SOL turbulence observed by a fast visible camera allowed visualize turbulent structures without perturbing plasma. Dependence power threshold on...
The generalized Buneman dispersion relation for two-component plasma is derived in the case of nonzero pressure both components and longitudinally dominated magnetic field. also valid other field configurations mentioned paper. It can be useful a variety systems, example, analyses jet penetrating into background plasma, beam-plasma physics, tests various magnetohydrodynamics (MHD) hybrid numerical codes designed magnetized plasmas.
A low energy (500 J) discharge at relatively high pressure (kPa) between two cone-shaped electrodes has been studied. The geometry enables the formation of jets with filaments and a compact plasmoid in center. existence was discovered our experiments. Electron density temperature were measured by standard interferometric, schlieren, spectroscopic methods. turbulent structure proposed for explanation values some parameters estimated.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...
An application study of modern pixel semiconductor detectors for characterization runaway electron events in tokamaks is presented. Characterization techniques utilizing both spectroscopic measurements and monitoring the intensity secondary X-rays produced by electrons were used. Energy spectra time evolutions their on two (Golem Compass) measured under different conditions compared with results standard diagnostics. The energy have similar exponential shapes but a significant variation...
The two-stream instability is a common instability, responsible for many observed phenomena in nature, especially the interaction of jets various origin with background plasma (e.g. extragalactic jet interacting cosmic background). dispersion relation not considering magnetic field described by well-known Buneman relation. In 2011, Bohata, Bren, and Kulhanek derived without cold limit, general orientation field, arbitrary stream directions. maximum value imaginary part individual branches...
Fully three dimensional PIC program package for the helical pinch numerical simulation was developed in our department. Both electromagnetic and gravitational interactions are incorporated into model. Collisions treated via Monte Carlo methods. The enabled to prove conditions of onset spiral structures pinch.
The Z-pinch is formed in a low-pressure pulsed discharge between two conical electrodes having an axial symmetry. In such configuration, plasma jet can be created. Results of study by schlieren and interferometric diagnostics are used to design apparatus with similar electrode which the effect drives through hole cathode toward metallic surface placed behind anode. Preliminary results on pulse coating target material from both anode chamber filling gas presented.< <ETX...
Runaway electrons are a potential threat in many plasma devices. At high velocities, the acceleration is not further offset by collisions plasma, as ohmic regime. The particles obtain relativistic velocity and considerable energy. A typical configuration includes parallel electric magnetic fields, which there no drifts, movement of charged combination gyration motion with an field. It follows from Lorentz equation that transverse component (perpendicular to fields) will be interconnected...
There are presented the implications of interferometric, schlieren and spectroscopic diagnostics in diode pulse discharge nitrogen between two cone‐shaped electrodes (discharge energy 0.5 kJ, max. current 50 kA, 1 st period 4 μs, gas pressure 5 kPa).In this discharge, there formed jets with filamentary structure due to inertial force ions layer. These accelerate evaporated from breakdown layer into central part discharge. The filaments shape both relatively stable during first halfperiod...
Bremsstrahlung and synchrotron radiation from the moving charged particles was calculated in planet magnetospheres. A program package RADIATION developed for these calculations. The radiative intensity is projected on a far sphere. directional dependence of during penetration through polar cusp calculated. can be also used treating plasma cluster penetrating electric double layer, MHD compress magnetic bow shock, fibers pinches other important situations. Intensity derived advanced retarded...
Abstract