O. Neubauer
A5006016532- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Ionosphere and magnetosphere dynamics
- Nuclear Materials and Properties
- Laser-induced spectroscopy and plasma
- Nuclear reactor physics and engineering
- Solar and Space Plasma Dynamics
- Nuclear Physics and Applications
- Electromagnetic Launch and Propulsion Technology
- Atomic and Molecular Physics
- Spacecraft and Cryogenic Technologies
- Geophysics and Gravity Measurements
- Astro and Planetary Science
- Laser Design and Applications
- Astronomical Observations and Instrumentation
- Particle Accelerators and Free-Electron Lasers
- Metallurgical Processes and Thermodynamics
- Electromagnetic Compatibility and Measurements
- Astronomy and Astrophysical Research
- Gas Dynamics and Kinetic Theory
- Geophysics and Sensor Technology
Forschungszentrum Jülich
2015-2024
Max Planck Institute for Plasma Physics - Greifswald
2016-2019
Atlas Copco (Germany)
2018
Huazhong University of Science and Technology
2018
Institute of Plasma Physics
2018
Chinese Academy of Sciences
2018
Max Planck Society
2017
Max Planck Institute for Plasma Physics
2017
Australian National University
2016
Oak Ridge National Laboratory
2016
Operating ITER in the reference inductive scenario at design values of Ip = 15 MA and QDT 10 requires achievement good H-mode confinement that relies on presence an edge transport barrier whose pedestal pressure height is key to plasma performance. Strong gradients occur such conditions can drive magnetohydrodynamic instabilities resulting localized modes (ELMs), which produce a rapid energy loss from region facing components (PFC). Without appropriate control, heat loads PFCs during ELMs...
The Wendelstein 7-X (W7-X) optimized stellarator fusion experiment, which went into operation in 2015, has been operating since 2017 with an un-cooled modular graphite divertor. This allowed first divertor physics studies to be performed at pulse energies up 80 MJ, as opposed 4 MJ the phase, where five inboard limiters were installed instead of a This, and number other upgrades device capabilities, extension regimes higher plasma density, heating power, performance overall, e.g. setting new...
The investigation of edge plasmas at the stellarator W7-X requires a flexible tool for integration variety different diagnostics as e.g. electrical probes, probing magnetic coils, material collection, or exposition and gas injection. A multi-purpose manipulator (MPM) system has been developed attached to vessel before operational phase 1.1. was designed user facility many diagnostics, which can be mounted on unique interface without breaking vacuum. system, located in equatorial plane,...
The first results of the Dynamic Ergodic Divertor in TEXTOR, when operating m/n=3/1 mode configuration, are presented. deeply penetrating external magnetic field perturbation this configuration increases toroidal plasma rotation. Staying below excitation threshold for m/n=2/1 tearing mode, rotation is always direction current, even if projection rotating opposite direction. observed consistent with a radial electric field, generated by an enhanced electron transport ergodic layers near...
Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters December 2015. At end of 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were operation, allowing detailed studies many interesting plasma phenomena. For example, fast neutral gas manometers supported video cameras (including one fast-frame camera frame rates...
TEXTOR is the Tokamak Experiment for Technology Oriented Research in field of plasma-wall interaction. The scope includes a detailed analysis particle and energy exchange between plasma surrounding chamber as well active measures to optimize first wall boundary region. medium-sized tokamak belonging class moderate-field but large-volume devices having circular cross section an iron core. major radius 1.75 m, minor 0.47 m. maximum current 0.8 MA, 3 T, pulse length 10 s. fed directly from...
The stellarator fusion experimental device Wendelstein 7-X (W7-X) is presently under assembly at the Greifswald branch of Max-Planck-Institut für Plasmaphysik, Germany. superconducting magnet system consists 50 nonplanar coils, 20 planar a bus system, and 14 current leads. It organized in seven electrical circuits with ten for interconnection, two leads each. cooled by supercritical helium. enclosed cryostat an outer diameter 16 m formed plasma vessel vessel. There are five different types...
Wendelstein 7-X (W7-X) is a large optimized stellarator (B=2.5T, V=30m3) aiming at demonstrating the reactor relevance of stellarators. In 2015 W7-X will begin its first operation phase (OP1.1) with five inertially cooled inboard limiters made graphite. Assuming heat loads can be spread out evenly between limiters, 1 second discharges 2 MW ECRH heating power could run in OP1.1. The expected plasma parameters sufficient to demonstrate readiness installed diagnostics and even physics program....
The current status of the mechanical and electromagnetic design for ICRF antenna system W7-X is presented. Two plugins are discussed: one consisting a pair straps with pre-matching to cover first frequency band, 25–38 MHz, second two short strap triplets band around 76 MHz. This paper focusses on lower band. Power coupling reference plasma profile studied help codes TOPICA Microwave Studio that deliver scattering matrix needed optimization geometric parameters box. Radiation power spectra...
Abstract W7-X completed its plasma operation in hydrogen with island divertor and inertially cooled test unit (TDU) made of graphite. A substantial set plasma-facing components (PFCs), including particular marker target elements, were extracted from the vessel analysed post-mortem. The analysis provided key information about underlying plasma–surface interactions (PSI) processes, namely erosion, transport, deposition as well fuel retention graphite components. net carbon (C) erosion...
Wendelstein 7-X (W7-X), started operation in December 2015 with a limiter configuration. In conjunction the multi-purpose manipulator, carrier for fast reciprocating probe systems, combined has been installed. This is able to measure local electron temperatures and densities, magnetic field, electric field plasma flow. These parameters are very useful ascertaining edge perfomance. addition, line tracing feature of W7-X webservices was used calculate connection length along path probe, each
For the ITER-like wall project at JET present main chamber CFC tiles will be exchanged with Be and in parallel a fully tungsten-clad divertor prepared. Therefore three R&D programmes were initiated: coatings on Inconel as well erosion markers developed for first of chamber. High heat flux screening cyclic loading tests carried out showed excellent performance, above required power energy density. conceptual design bulk W horizontal target plate was investigated, emphasis minimizing...
Recently, the dynamic ergodic divertor (DED) of TEXTOR has been studied in an m/n = 3/1 set-up which is characterized by a relatively deep penetration perturbation field. The field creates (a) helical divertor, (b) pattern and/or (c) excitation tearing modes, depending on whether DED current static, rotating co-current direction or counter-current direction. Characteristic properties such as high recycling regime enhanced shielding have studied. A strong effect ergodization spin up plasma...
For the first operation phase of optimized stellarator W7-X, a heterodyne poloidal correlation reflectometry diagnostic is installed and put into operation. The system intended to measure perpendicular (with respect magnetic field) turbulence rotation properties, such as decorrelation time length at plasma edge. Furthermore, it can give information on field line pitch angle. consists an array microwave antennas distributed in toroidal directions. frequency range 22 GHz–40 GHz allows us...
A group of edge diagnostics and modelling has been developed for investigation synergy between 3D physics plasma-wall interactions on Wendelstein 7-X (W7-X). Two endoscopes have designed visible ultraviolet spectroscopy tomography the plasma edge, along with infrared thermography divertor tiles. 2D profiles impurities (e.g. helium, carbon) will be measured by two viewing island region in a spatial resolution <2 mm. multipurpose manipulator, which is used as carrier either probe head...
Wendelstein 7-X (W7-X) is a nearly full-carbon machine with graphite divertors, baffles and shields in Operation Phase 1.2b (OP 1.2b). Divertor spectrometer measurements showed that an amount of helium oxygen impurities existed the predominately hydrogen plasma, which resulted high carbon impurity level by enhanced physical chemical sputtering these comparison pure impinging proton yields. In order to improve wall conditions, especially reduce content, boronizations were applied OP1.2b....