A5042682358- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Particle accelerators and beam dynamics
- Fusion materials and technologies
- Advanced Battery Materials and Technologies
- Supercapacitor Materials and Fabrication
- Digital Holography and Microscopy
- Laser-Matter Interactions and Applications
- Advanced Fiber Laser Technologies
- Gyrotron and Vacuum Electronics Research
- Advancements in Battery Materials
- Magnetic properties of thin films
- Photocathodes and Microchannel Plates
- Orbital Angular Momentum in Optics
- Laser-induced spectroscopy and plasma
- Cold Atom Physics and Bose-Einstein Condensates
- Superconducting Materials and Applications
- Photorefractive and Nonlinear Optics
- Advanced Optical Imaging Technologies
- Glass properties and applications
- Material Dynamics and Properties
- Quantum Information and Cryptography
- Electron and X-Ray Spectroscopy Techniques
Burapha University
2017-2023
Heinrich Heine University Düsseldorf
2013-2015
Magnetic turbulence is observed at the beginning of current quench in intended TEXTOR disruptions. Runaway electron (RE) suppression has been experimentally found magnetic larger than a certain threshold. Below this threshold, generated RE inversely proportional to level turbulence. The originates from background plasma and amplitude depends strongly on toroidal field density. These results explain previously threshold for generation have be considered predictions ITER.
Lithium iron phosphate (LFP) is widely used as an active material in a cathode electrode for lithium-ion batteries (LIBs). LFP has many remarkable properties such high working voltage and excellent thermal stability. However, it suffers with slow ion diffusion low electrical conductivity. Graphene foam outstanding large surface area great These are suitable improving the electrode. In this work, graphene was synthesized by chemical vapor deposition. The prepared dropping on foam. We found...
Investigations of runaway electrons (REs) during induced disruptions are performed at the TEXTOR tokamak. The synchrotron radiation generated by REs in plasma core is detected using an infrared camera. measurements enable observation structure and dynamics beam. In particular, beam investigated as a function vertical horizontal control fields. From current number 4.33 × 1016 was calculated. with energies exceeding 25 MeV 6.4 1015 according to measurement end quench phase. mean pitch angle...
We introduce a method for measuring periodic structure, particularly grating period. The is based on the high-precision laser Talbot effect. combination of rubidium-locked external cavity diode and interferometer provides an excellent simple tool this purpose. Some experimental results are provided to demonstrate approach.
The evolution of runaway electrons in disruptive plasmas TEXTOR is determined by observing the synchrotron radiation (hard component E > 25 MeV) and measuring runway with an energy a few MeV using scintillator probe. Disruptions are initiated massive argon gas injection performed fast valve. observed beam high (synchrotron radiation) fills about half diameter original plasma. smooth shows no indication filamentation. initial conditions all cases very similar. temporal development electrons,...
A new physical mechanism of formation runaway electron beams during plasma disruptions in tokamaks is proposed. The disruption caused by a strong stochastic magnetic field formed due to nonlinearly excited low-mode number magnetohydrodynamic (MHD) modes. It conjectured that the beam central region confined inside intact surface located between q = 1 and closest low–order rational surfaces [q 5/4 or 4/3,…]. results current has helical nature with predominant m/n 1/1 component. thermal quench...
Experimental evidence supporting the theory of hot tail runaway electron (RE) generation has been identified in TEXTOR disruptions. With higher temperature, more REs are generated during thermal quench. Increasing RE by increasing an obvious plateau is observed even with low toroidal magnetic field (1.7 T). These results explain previously found density threshold for generation.
Based on the analysis of data from numerous dedicated experiments plasma disruptions in TEXTOR tokamak mechanisms formation runaway electron (RE) beams and their losses are proposed. The disruption is caused by a strong stochastic magnetic field formed due to nonlinearly excited low-mode-number magneto-hydro-dynamics (MHD) modes. It hypothesized that RE beam central region confined an intact surface acceleration electrons inductive toroidal electric field. In case plasmas with safety factor...
Based on the analysis of data from numerous dedicated experiments plasma disruptions in TEXTOR tokamak mechanisms formation runaway electron beams and their losses are proposed. The disruption is caused by strong stochastic magnetic field formed due to nonlinearly excited low-mode number magnetohydrodynamic (MHD) modes. It hypothesized that beam central region confined an intact surface acceleration electrons inductive toroidal electric field. In case plasmas with safety factor $q(0)<1$...
By making use of advanced technique the near-field Talbot effect, we design a novel spectrometer. Our method provides compact and portable spectrometer according to characteristic effect. Here, propose idea with simulations done reasonable values. With vibration temperature adjustments, high resolution over range few nanometers can be obtained.
Long-pulse steady-state discharges with lower hybrid current drive were successfully obtained in the limiter configuration machine, Tore Supra. The hard x-ray (HXR) diagnostic system Supra associated tomographic inversion provided a good approximation of power deposition profile. accurate plasma control through this reconstruction leads to an improvement confinement. was upgraded WEST, Tungsten (W) Environment Steady-state Tokamak. geometry changed D-shaped geometry. Therefore, novel code...
Abstract This work aimed to enhance a resolution of the electron diffraction pattern by improving longitudinal and lateral coherence beam. Using uniform magnetic field slits is cheap straightforward method. However, such magnet requires larger space. Smaller solenoids which create non-uniform are more applicable, especially when space was limited. bTherefore, effect on energy spread beam investigated numerically experimentally. The simulation results agreed well (within 10%) with...
The loss of runaway electrons during an induced disruption is recorded by a synchrotron imaging technique using fast infrared CCD camera. predominantly diffuse. During the “spiky-loss phase”, when beam moves close to wall, narrow channel between column and scintillator probe formed lasts until terminated. In some cases, processed images show stripe pattern at plasma edge. A comparison MHD dominated disruptions MHD-free performed. new mechanism with electron generation novel model which...
Abstract Electron diffraction is not solely a powerful method to study fundamental physics but has also been applied quantum sensors. A low-coherence electron source results in drop of fringe contrast. One approach enhance visibility the pattern improve longitudinal coherence an beam. When electrons pass through magnetic field, they experience force which bends them circular paths. Electrons with different energies will travel along By placing slit behind width energy distribution become...
Abstract Molecular dynamics simulations have been carried out to investigate the effect of inertia on both and locally favoured structures (LFS) a supercooled liquid toward glass transition. In this work, equimolar binary mixtures Hard Spheres with same diameter but different masses were studied. The mass ratio system was 2:1. simulation performed sampled by using microcanonical ensemble. Both structure changing analysed. A cluster analysis detected topological classification (TCC) based...
Abstract Near-field diffraction has been widely studied and applied in many research fields including optics, quantum mechanics sensor technology. High accuracy sensors, for instance, have developed based on the Talbot effect, i.e., self-imaging due to high sensitivity of near-field pattern. Since visibility pattern depends intensively velocity distribution wavefront incoming wave, Talbot-Lau effect is generally used improve spatial coherence incident wave hence a better fringe contrast....