A5084378679- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Solar and Space Plasma Dynamics
- Superconducting Materials and Applications
- Fusion materials and technologies
- Advanced Data Storage Technologies
- Parallel Computing and Optimization Techniques
- Dust and Plasma Wave Phenomena
- Quantum Information and Cryptography
- Laser-induced spectroscopy and plasma
- Electromagnetic Launch and Propulsion Technology
- Nuclear reactor physics and engineering
- Distributed and Parallel Computing Systems
- Fluid Dynamics Simulations and Interactions
- Gas Dynamics and Kinetic Theory
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Computing Algorithms and Architecture
- Fluid Dynamics and Turbulent Flows
- Atomic and Molecular Physics
- Inertial Sensor and Navigation
- Electromagnetic Simulation and Numerical Methods
- Computational Fluid Dynamics and Aerodynamics
George Mason University
2025
University of Colorado Boulder
2015-2024
Duke University
2024
Los Alamos National Laboratory
1996-2023
Duke Medical Center
2019-2023
Duke University Hospital
2023
Ingenza (United Kingdom)
2022
Argonne National Laboratory
2013-2021
Princeton Plasma Physics Laboratory
1992-2021
Princeton University
1992-2021
The predictions of gyrokinetic and gyrofluid simulations ion-temperature-gradient (ITG) instability turbulence in tokamak plasmas as well some plasma thermal transport models, which have been widely used for predicting the performance proposed International Thermonuclear Experimental Reactor (ITER) [Plasma Physics Controlled Nuclear Fusion Research, 1996 (International Atomic Energy Agency, Vienna, 1997), Vol. 1, p. 3], are compared. These comparisons provide information on effects...
A new scheme that evolves the perturbed part of distribution function along a set characteristics solves fully nonlinear gyrokinetic equations is presented. This low-noise characteristic method for particle simulation an extension partially linear weighting scheme, and may be considered improvement over existing δf methods. Some features this include ability to keep all nonlinearities, particularly those associated with velocity space, use conventional loading techniques, also retention...
Results from a fully nonlinear three-dimensional toroidal electrostatic gyrokinetic simulation of the ion temperature gradient instability are presented. The model has adiabatic electrons and complete gyrophase-averaged dynamics, including trapped particles. include confirmation radially elongated ballooning mode structure predicted by linear theory, saturation these modes. ensuing turbulent spectrum retains remnants structure, very similar features as recent experimental fluctuation measurements.
We develop theoretical and numerical tools for the quantification of entanglement in systems with continuous degrees freedom. Continuous variable swapping is introduced based on this idea we methods purification systems. The success these then assessed using tools.
A three-dimensional (3-D) hybrid gyrokinetic-MHD (magnetohydrodynamic) simulation scheme is presented. To the 3-D toroidal MHD code, MH3D-K energetic particle component added as gyrokinetic particles. The resulting mh3d-k, used to study nonlinear behavior of effects in tokamaks, such stabilization sawteeth, fishbone oscillations, and alpha-particle-driven Alfvén eigenmode (TAE) modes.
A series of carefully designed experiments on DIII-D have taken advantage a broad set turbulence and profile diagnostics to rigorously test gyrokinetic simulations. In this paper the goals, tools performed in these validation studies are reviewed specific examples presented. It is found that predictions transport fluctuation levels mid-core region (0.4 < ρ 0.75) better agreement with experiment than those outer (ρ ⩾ where edge coupling effects may become increasingly important multiscale...
It is found from a heat-flux-driven full-f gyrokinetic particle simulation that there ion temperature gradient (ITG) turbulence across an entire L-mode-like edge density pedestal in diverted tokamak plasma which the mild without structure, hence normalized parameter ηi=(d log Ti/dr)/(d n/dr) varies strongly high (&gt;4 at top/shoulder) to low (&lt;2 slope) values. Variation of and ηi same scale as correlation length, compressing slope region. The resulting thermal flux on order...
MPI is the most prominent programming model used in scientific computing today. Despite importance of MPI, however, how applications use it production not well understood. This lack understanding attributed primarily to fact that systems are often wary incorporating automatic profiling tools perform such analysis because concerns about potential performance over-heads. In this study, we a lightweight tool, called Autoperf, log usage characteristics on large IBM BG/Q supercomputing system...
The Vlasov-Maxwell system of equations, which describes classical plasma physics, is extremely challenging to solve, even by numerical simulation on powerful computers. By linearizing and assuming a Maxwellian background distribution function, we convert the into Hamiltonian problem. Then for limiting case electrostatic Landau damping, design verify quantum algorithm, appropriate future error-corrected universal computer. While has costs that scale as $\mathcal{O}(N_v t)$ velocity grid with...
It is commonly assumed that Shor's quantum algorithm for the efficient factorization of a large number N requires pure initial state. Here we demonstrate single qubit, together with collection log 2N qubits in an arbitrary mixed state, sufficient to implement efficiently.
Joint experiment/theory/modelling research has led to increased confidence in predictions of the pedestal height ITER. This work was performed as part a US Department Energy Research Target FY11 identify physics processes that control H-mode structure. The study included experiments on C-Mod, DIII-D and NSTX well interpretation experimental data with theory-based modelling codes. provides ability models for peeling–ballooning stability, bootstrap current, width scaling make correct...
The increasing complexity of HPC systems has introduced new sources variability, which can contribute to significant differences in run-to-run performance applications. With components at various levels the system contributing application developers and users are now faced with difficult task running tuning their applications an environment where measurements vary by as much a factor two three. In this study, we classify, quantify, present ways mitigate variability on Cray XC Intel Xeon Phi...
The simulation of large nonlinear dynamical systems, including systems generated by discretization hyperbolic partial differential equations, can be computationally demanding. Such are important in both fluid and kinetic computational plasma physics. This motivates exploring whether a future error-corrected quantum computer could perform these simulations more efficiently than any classical computer. We describe method for mapping finite system to an infinite linear (embedding) detail three...
D2C7-immunotoxin (IT), a dual-specific IT targeting wild-type epidermal growth factor receptor (EGFR) and mutant EGFR variant III (EGFRvIII) proteins, demonstrates encouraging survival outcomes in subset of patients with glioblastoma. We hypothesized that immunosuppression glioblastoma limits D2C7-IT efficacy. To improve the response rate reverse immunosuppression, we combined tumor cell killing αCD40 costimulation antigen-presenting cells. In murine glioma models, single intratumoral...
Gyrokinetic δf particle simulation is used to investigate the nonlinear saturation mechanisms in collisionless trapped electron mode (CTEM) turbulence. It found that importance of zonal flow parameter-sensitive and well characterized by shearing rate formula. The effect empirically be sensitive temperature ratio, magnetic shear, gradient. For parameters where unimportant, density (purely radial perturbations) generated expected dominant mechanism. A toroidal mode-coupling theory presented...
Trapped electron mode (TEM) turbulence exhibits a rich variety of collisional and zonal flow physics. This work explores the parametric variation flows underlying mechanisms through series linear nonlinear gyrokinetic simulations, using both particle-in-cell continuum methods. A new stability diagram for modes is presented, identifying critical boundary at ηe=1, separating long short wavelength TEMs. novel parity test used to separate TEMs from temperature gradient driven modes. scan ηe...
Global electromagnetic gyrokinetic simulations show the existence of near threshold conditions for both a high-$n$ kinetic ballooning mode (KBM) and an intermediate-$n$ version peeling-ballooning (KPBM) in edge pedestal two DIII-D H-mode discharges. When magnetic shear is reduced narrow region steep pressure gradient, KPBM significantly stabilized, while KBM weakly destabilized hence becomes most-unstable mode. Collisions decrease KBM's critical $\ensuremath{\beta}$ increase growth rate.
D2C7-IT is a novel immunotoxin (IT) targeting wild-type epidermal growth factor receptor (EGFRwt) and mutant EGFR variant III (EGFRvIII) proteins in glioblastoma. In addition to inherent tumoricidal activity, immunotoxins induce secondary immune responses through the activation of T cells. However, glioblastoma-induced suppression major obstacle an effective durable immunotoxin-mediated antitumor response. We hypothesized that D2C7-IT-induced response could be effectively augmented...
We simulate the dynamics, including laser cooling, of three-dimensional (3-D) ion crystals confined in a Penning trap using newly developed molecular dynamics-like code. The numerical integration ions’ equations motion is accelerated fast multipole method to calculate Coulomb interaction between ions, which allows us efficiently study large with thousands ions. In particular, we show that simulation time scales linearly number, rather than square number. By treating absorption photons as...
Abstract Recent advances in GYRO allow simulations to map out the linear stability of many eigenvalues and eigenvectors gyrokinetic equation (as opposed only most unstable) at low computational cost. In this work, GYRO's new capabilities are applied a pressure scan about pedestal region DIII-D shot 131997. MHD calculations infinite- n limit ideal ballooning mode, used very successful EPED model predict height width, demonstrate clear onset instability 70% experimental pressure. Presented...