Matthew Beidler
A5063255433- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Fusion materials and technologies
- Superconducting Materials and Applications
- Magnetic Field Sensors Techniques
- Geomagnetism and Paleomagnetism Studies
- Plasma Diagnostics and Applications
- Nuclear reactor physics and engineering
- Solar and Space Plasma Dynamics
- Laser-Plasma Interactions and Diagnostics
- Geophysical and Geoelectrical Methods
- Electromagnetic Simulation and Numerical Methods
- Magnetic Properties and Applications
- Electromagnetic Scattering and Analysis
- Neural Networks and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Nuclear Materials and Properties
- Semiconductor materials and devices
- Catalytic Processes in Materials Science
- Software System Performance and Reliability
- Cold Fusion and Nuclear Reactions
- Age of Information Optimization
- Photocathodes and Microchannel Plates
- Dust and Plasma Wave Phenomena
- NMR spectroscopy and applications
Oak Ridge National Laboratory
2020-2024
Culham Science Centre
2024
Culham Centre for Fusion Energy
2024
University of Wisconsin–Madison
2017-2022
Government of the United States of America
2022
Princeton Plasma Physics Laboratory
2022
West Virginia University
2011-2016
Abstract The JET 2019–2020 scientific and technological programme exploited the results of years concerted engineering work, including ITER-like wall (ILW: Be W divertor) installed in 2010, improved diagnostic capabilities now fully available, a major neutral beam injection upgrade providing record power 2019–2020, tested technical procedural preparation for safe operation with tritium. Research along three complementary axes yielded wealth new results. Firstly, plasma delivered scenarios...
Abstract In 2021 JET exploited its unique capabilities to operate with T and D–T fuel an ITER-like Be/W wall (JET-ILW). This second major campaign (DTE2), after DTE1 in 1997, represented the culmination of a series enhancements—new fusion diagnostics, new injection capabilities, refurbishment plant, increased auxiliary heating, in-vessel calibration 14 MeV neutron yield monitors—as well as significant advances plasma theory modelling community. DTE2 was complemented by sequence isotope...
The objective of thermonuclear fusion consists producing electricity from the coalescence light nuclei in high temperature plasmas. most promising route to envisages confinement such plasmas with magnetic fields, whose studied configuration is tokamak. Disruptions are catastrophic collapses affecting all tokamak devices and one main potential showstoppers on a commercial reactor. In this work we report how, deploying innovative analysis methods thousands JET experiments covering isotopic...
Relativistic electron (RE) beams at high current density (low safety factor, qa) yet very low free-electron accessed with D2 secondary injection in the DIII-D and JET tokamak are found to exhibit large-scale MHD instabilities that benignly terminate RE beam. In JET, this technique has enabled termination of MA-level currents without measurable first-wall heating. This scenario thus offers an unexpected alternate pathway achieve mitigation collisional dissipation. Benign is explained by two...
Abstract The thermo-mechanical response of an ATJ graphite sample to controlled runaway electron (RE) dissipation, realized in DIII-D, is modelled with a novel work-flow that features the RE orbit code KORC, Monte Carlo particle transport Geant4 and finite element multiphysics software COMSOL. KORC provides striking positions momenta, calculates volumetric energy deposition COMSOL simulates thermoelastic response. Brittle failure predicted according maximum normal stress criterion, which...
Abstract Post-disruption runaway electron (RE) kinetic energy K and pitch angle sin are critical parameters for determining resulting first wall material damage during strikes, but very challenging to measure experimentally. During the final loss instability, confined RE reconstructed center-post strikes both high impurity (high-Z) low (low-Z) plasmas by combining soft x-ray, hard synchrotron emission, total radiated power measurements. Deconfined (wall impacting) sinθ is then these shots...
A model for incomplete reconnection in sawtooth crashes is presented. The inflow during the crash phase of sawteeth self-consistently convects high pressure core toward site, raising gradient there. Reconnection shuts off if diamagnetic drift speed at site exceeds a threshold, which may explain reconnection. relaxation magnetic shear after stops destabilization ideal interchange instabilities reported previously. Proof-of-principle two-fluid simulations confirm this basic picture....
Abstract DIII-D physics research addresses critical challenges for the operation of ITER and next generation fusion energy devices. This is done through a focus on innovations to provide solutions high performance long pulse operation, coupled with fundamental plasma understanding model validation, drive scenario development by integrating core boundary plasmas. Substantial increases in off-axis current efficiency from an innovative top launch system EC power, pressure broadening Alfven...
Abstract Subcritical energetic electrons (SEEs) produced by the runaway electron (RE) avalanche source at energies below threshold are found to be primary contributor surface heating of plasma-facing components (PFCs) during final loss events. This finding is supported theoretical analysis, computational modeling with Kinetic Orbit Runaway Code (KORC), and qualitative agreement DIII-D experimental observations. The generates significantly more secondary threshold, which thermalize rapidly...
A new regime of fast magnetic reconnection with an out-of-plane (guide) field is reported in which the key role played by electron pressure anisotropy described Chew-Goldberger-Low gyrotropic equations state generalized Ohm's law, even dominates Hall term. description physical cause this behavior provided and two-dimensional fluid simulations are used to confirm results. The causes develop a quadrupole structure opposite polarity gives rise dispersive waves. In addition being important for...
The nonlinear, extended-magnetohydrodynamic (MHD) code NIMROD is benchmarked with the theory of time-dependent forced magnetic reconnection induced by small resonant fields in slab geometry context visco-resistive MHD modeling. Linear computations agree time-asymptotic, linear flow screening externally applied fields. inclusion nonlinear can result mode penetration due to balance between electromagnetic and viscous forces time-asymptotic state, which produces bifurcations from a high-slip...
Abstract The DIII-D tokamak has elucidated crucial physics and developed projectable solutions for ITER fusion power plants in the key areas of core performance, boundary heat particle transport, integrated scenario operation, with closing core-edge integration knowledge gap being overarching mission. New experimental validation high-fidelity, multi-channel, non-linear gyrokinetic turbulent transport models provides strong confidence it will achieve Q ⩾ 10 operation. Experiments identify...
Three dimensional magnetic fields in tokamaks can induce forced reconnection (FMR) and produce islands on resonant surfaces. Conventional analytic solutions to FMR focus describing the time asymptotic state given a steady-state field error. The of this work is understand nonlinear dynamics mode penetration, an evolution from high-slip, flow-screened metastable equilibrium into low-slip, field-penetrated equilibrium. In work, we extend previous by incorporating temporally varying external as...
We diagnose local properties of magnetic reconnection during a sawtooth crash employing the three-dimensional toroidal, extended-magnetohydrodynamic (MHD) code M3D-C1. To do so, we sample simulation data in plane which occurs, perpendicular to helical mode at q = 1 surface, where m and n are poloidal toroidal numbers is safety factor. study nonlinear evolution particular test equilibrium non-reduced field representation using both resistive-MHD extended-MHD models. find growth rates for...
New simulations with the Kinetic Orbit Runaway electron (RE) Code (KORC) show RE deconfinement losses to wall during plasma scrape off are primary current dissipation mechanism in DIII-D experiments high-Z impurity injection, and not collisional slowing down. The majority of also exhibit an increase beam energy due acceleration by induced toroidal electric field, even while is decreasing. In this study, KORC integrates orbits using relativistic guiding center equations motion incorporates...
A numerical study of magnetohydrodynamics (MHD) and tracer-particle evolution investigates the effects resonant magnetic perturbations (RMPs) on confinement runaway electrons (REs) in tokamak discharges conducted Madison Symmetric Torus. In computational results applying RMPs having a broad toroidal spectrum but single poloidal harmonic, m = 1 RMP does not suppress REs, whereas 3 achieves significant deconfinement complete suppression obtained experiment [Munaretto et al., Nuclear Fusion 60,...
Runaway electrons (RE) generated during magnetic disruptions present a major threat to the safe operation of plasma nuclear fusion reactors. A critical aspect understanding RE dynamics is calculate runaway probability, i.e., probability that an electron in phase space will on, or before, prescribed time. Such can be obtained by solving adjoint equation underlying Fokker-Planck controls dynamics. In this effort, we sparse-grid probabilistic scheme for computing probability. The key ingredient...