A5046483710- Magnetic confinement fusion research
- Fusion materials and technologies
- Plasma Diagnostics and Applications
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Nuclear Materials and Properties
- Nuclear reactor physics and engineering
- Metal and Thin Film Mechanics
- Laser-induced spectroscopy and plasma
- Particle Accelerators and Free-Electron Lasers
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Ion-surface interactions and analysis
- Solar and Space Plasma Dynamics
- Spacecraft and Cryogenic Technologies
- Gyrotron and Vacuum Electronics Research
- Muon and positron interactions and applications
- Magnetic Field Sensors Techniques
- Scientific Research and Discoveries
- Meteorological Phenomena and Simulations
- Diamond and Carbon-based Materials Research
- Spectroscopy and Laser Applications
- Atomic and Subatomic Physics Research
Oak Ridge National Laboratory
2015-2025
University of Tennessee at Knoxville
2016-2021
University of Illinois Urbana-Champaign
2018-2021
Pennsylvania State University
2021
National Technical Information Service
2021
Office of Scientific and Technical Information
2021
University of Florida
2017-2018
Culham Science Centre
2003-2013
Royal Military Academy
2013
Max Planck Institute for Plasma Physics
2013
The onset of a neoclassical tearing mode (NTM) depends on the existence large enough seed island. It is shown in Joint European Torus that NTMs can be readily destabilized by long-period sawteeth, such as obtained sawtooth stabilization from ion-cyclotron heating or current drive. This has important implications for burning plasma scenarios, alpha particles strongly stabilize sawteeth. also that, adding and drive just outside inversion radius, sawteeth are destabilized, resulting shorter...
Polycrystalline, annealed tungsten targets were bombarded with 12.3 MeV W 4+ ions to various damage levels. Deuterium was implanted by high-flux plasmas in Pilot-PSI (>10 24 m −2 s −1 ) at a surface temperature below 525 K. retention has been studied nuclear reaction analysis and thermal desorption spectroscopy. We found that deuterium is strongly enhanced the bombardment saturation occurs fluence of about 3 × 10 17 . The maximum concentration damaged region measured be 1.4 at.%. This...
Abstract Since the publication of review Progress in ITER Physics Basis (PIPB) 2007, significant progress has been made understanding processes at plasma-material interface. This review, part ITPA Nuclear Fusion Special Issue On Path to Burning Plasma Operation , presents these developments, focusing on key areas such as physics plasma exhaust, interactions, and properties plasma-facing materials their evolution under exposure. The coordinated efforts Topical Group Scrape-Off Layer Divertor...
The availability of future fusion devices, such as a nuclear science facility or demonstration power station, greatly depends on long operating lifetimes plasma facing components in their divertors. ORNL is designing the Material Plasma Exposure eXperiment (MPEX), superconducting magnet, steady-state device to address material interactions reactors. MPEX will utilize new highintensity source concept based RF technology. This allow experiment cover entire expected conditions divertor reactor....
Stationary high energy confinement is observed on TEXTOR-94 for times limited only by the flux swing of transformer using strong edge radiation cooling. Necessary tools are feedback control radiated power and plasma content. At highest densities obtained (up to 1.2 Greenwald limit), exceeds edge-localized-mode-free H-mode scaling ITERH93-P more than 20%. β limits reached with fH89/qa≈0.6. No detrimental effect seeded impurity seen. These discharges meet many conditions necessary a fusion...
Impurity injection in the JET ELMy H-mode regime has produced high-confinement, quasi-steady-state plasmas with densities close to Greenwald density. However, at large Ar densities, a sudden loss of confinement is observed. A possible correlation between and observed MHD phenomena, both core edge plasma, was considered. The degradation coincided impurity profile peaking following disappearance sawtooth activity. In addition, density analysis confirmed that central modes prevented peaking....
The main objective of this paper is investigation methods for reduction divertor heat loads in order to increase the lifetime tiles future fusion reactors.Special emphasis given studies transient due edge localized modes (ELMs).Two are compared: argon seeded type-I ELMy H-modes and nitrogen type-III H-modes.In both scenarios, impurity seeding leads a pedestal energy hence released by ELM.This consequentially reduces power load targets.At high radiative fractions H-modes, part that ELM (small...
Two sets of identical tungsten (W) targets are irradiated at 300 K with 12.3 MeV W 4+ ions to peak damage levels ranging from 0.5 10 displacements per atom (dpa). This results in a profile that is peaked ∼0.8 µm and extends depth ∼1.5 µm. Both exposed high-density ( n e,center = 3 × 20 m −3 ), low-temperature T 1.6 eV) deuterium (D) plasma Pilot-PSI. One set high surface temperatures 950–680 K) the other low 480–340 K). The temperature determined by local conditions. Nuclear reaction...
The thermal expansion of 15 alkali halides has been investigated from 70 to 570 K. single-crystal specimens LiF, LiCl, LiBr, NaF, NaCl, NaBr, NaI, KF, KCl, KBr, KI, RbI, CsCl, CsBr, and CsI are examined using a high-precision differential dilatometer in conjunction with an electronic micrometer. results compared those available the literature found be reasonable agreement. Grüneisen parameter γ calculated present data. For given cation group, value is very close, but increase size decreases...
An advanced Thomson scattering system has been built for a linear plasma generator surface interaction studies. The is based on Nd:YAG laser operating at the second harmonic and detection branch featuring high etendue (f/3) transmission grating spectrometer equipped with an intensified charged coupled device camera. able to measure electron density (n(e)) temperature (T(e)) profiles close output of source and, distance 1.25 m, just in front target. enables 50 spatial channels about 2 mm...
Linear plasma generators are cost effective facilities to simulate divertor conditions of present and future fusion reactors. They used address important R&D gaps in the science material interactions towards viable facing components for Next generation have be able access expected on targets ITER devices. The steady-state linear device MPEX will this regime with electron temperatures 1–10 eV densities . resulting heat fluxes about 10 MW is designed deliver those a novel Radio Frequency...
Purpose: Extracting and structuring relevant clinical information from electronic health records (EHRs) remains a challenge due to the heterogeneity of systems, documents, documentation practices. Large Language Models (LLMs) provide an approach processing semi-structured unstructured EHR data, enabling classification, extraction, standardization. Methods: Medical documents are processed through structured data pipeline generate normalized FHIR data. Unstructured undergoes preprocessing,...
A microwave interferometry technique is applied for the first time detecting a discrete spectrum of Alfvén cascade (AC) eigenmodes excited with fast ions in reversed magnetic shear plasmas Joint European Torus. The measurements plasma density perturbations associated ACs show an unprecedented frequency and resolution superior to that obtained external coils. are used monitoring evolution safety factor rational surfaces region maximum current.
This paper presents the results of JET experiments aimed at studying operational space plasmas with a Type III ELMy edge, in terms both local and global plasma parameters. In JET, regime has wide pedestal ne – Te diagram, ELMs are observed standard H-modes as well an internal transport barrier (ITB). The transition from H-mode to steady state I requires minimum loss power, PTypeI. PTypeI decreases increasing triangularity. critical temperature for is found be inversely proportional density...
AbstractA new era of fusion research has started with ITER being constructed and DEMO for power demonstration on the horizon. However, nuclear science needs to be developed before can designed. One most crucial complex outstanding issues solved is plasma surface interaction (PSI) in hostile environment a reactor. Not only are materials exposed unprecedented steady-state transient fluxes, but they also neutron fluxes. Both ion fluxes will change micro-structure facing significantly even...
Plasma-facing materials in the divertor of a magnetic fusion reactor have to tolerate steady state plasma heat fluxes range 10 MW/m2 for ∼107 s, addition neutron fluences, which can damage plasma-facing high displacements per atom (dpa) ∼50 dpa. Materials solutions needed components are yet be developed and tested. The material exposure experiment (MPEX) is newly proposed linear device designed deliver necessary flux target testing, including capability expose priori neutron-damaged samples...