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Annotated Bibliography of EDGE2D Use

Description: This annotated bibliography is intended to help EDGE2D users, and particularly new users, find existing published literature that has used EDGE2D. Our idea is that a person can find existing studies which may relate to his intended use, as well as gain ideas about other possible applications by scanning the attached tables.
Date: June 24, 2005
Creator: Strachan, J. D. & Corrigan, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Basics of Fusion-Fissison Research Facility (FFRF) as a Fusion Neutron Source

Description: FFRF, standing for the Fusion-Fission Research Facility represents an option for the next step project of ASIPP (Hefei, China) aiming to a first fusion-fission multifunctional device [1]. FFRF strongly relies on new, Lithium Wall Fusion plasma regimes, the development of which has already started in the US and China. With R/a=4/1m/m, Ipl=5 MA, Btor=4-6 T, PDT=50- 100 MW, Pfission=80-4000MW, 1 m thick blanket, FFRF has a unique fusion mission of a stationary fusion neutron source. Its pioneering… more
Date: June 3, 2011
Creator: Zakharov, Leonid E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of Gas Puff Imaging Data in NSTX with the DEGAS 2 Simulation

Description: Gas-Pu -Imaging (GPI) is a two dimensional diagnostic which measures the edge Dα light emission from a neutral Dα gas puff near the outer mid- plane of the National Spherical Torus Experiment (NSTX). DEGAS 2 is a 3-D Monte Carlo code used to model neutral transport and plasma-neutral interactions in fusion plasmas. In this paper, we compare the measured and modeled Dα light emission for speci c NSTX experiments. Both the simulated spatial distribution and radiance of the Dα light emission agree… more
Date: April 10, 2013
Creator: Cao, B.; Stotler, D. P.; Zweben, S. J.; Bell, M.; Diallo, A. & LeBlanc, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamical Evolution of Pedestal Parameters in ELMy H-mode in the National Spherical Torus Experiment

Description: Characterizations of the pedestal parameter dynamics throughout the edge localized modes(ELM) cycles are performed on the National Spherical Torus Experiment (NSTX, [M. Ono et al., Nucl. Fusion 40, 557 (2000)]). A clear buildup of the pedestal height is observed between ELMs for three di erent plasma currents, which tends to saturate prior to the onset of ELM at low and medium plasma current. Similarly, the pedestal width increases with no clear evidence of saturation during an ELM cycle. The m… more
Date: July 27, 2011
Creator: Diallo, A; Kubota, S; Sontag, A; Osborne, T; Podesta, M; Bell, R E et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge Ion Heating by Launched High Harmonic Fast Waves in NSTX

Description: A new spectroscopic diagnostic on the National Spherical Torus Experiment (NSTX) measures the velocity distribution of ions in the plasma edge simultaneously along both poloidal and toroidal views. An anisotropic ion temperature is measured during high-power high harmonic fast wave (HHFW) radio-frequency (rf) heating in helium plasmas, with the poloidal ion temperature roughly twice the toroidal ion temperature. Moreover, the measured spectral distribution suggests that two populations of ions … more
Date: December 1, 2004
Creator: Biewer, T. M.; Bell, R. E.; Diem, S. J.; Phillips, C. K.; Wilson, J. R. & Ryan, P. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge Minority Heating Experiment in Alcator C-Mod

Description: An attempt was made to control global plasma confinement in the Alcator C-Mod tokamak by applying ion cyclotron resonance heating (ICRH) power to the plasma edge in order to deliberately create a minority ion tail loss. In theory, an edge fast ion loss could modify the edge electric field and so stabilize the edge turbulence, which might then reduce the H-mode power threshold or improve the H-mode barrier. However, the experimental result was that edge minority heating resulted in no improvemen… more
Date: March 25, 2005
Creator: Zweben, S. J.; Terry, J. L.; Bonoli, P.; Budny, R.; Chang, C. S.; Fiore, C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge Plasma Boundary Layer Generated By Kink Modes in Tokamaks

Description: This paper describes the structure of the electric current generated by external kink modes at the plasma edge using the ideally conducting plasma model. It is found that the edge current layer is created by both wall touching and free boundary kink modes. Near marginal stability, the total edge current has a universal expression as a result of partial compensation of the δ-functional surface current by the bulk current at the edge. The resolution of an apparent paradox with the pressure balanc… more
Date: November 22, 2010
Creator: Zakharov, L.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Edge Rotation and Temperature Diagnostic on NSTX

Description: A new diagnostic for the National Spherical Torus Experiment (NSTX) is described whose function is to measure ion rotation and temperature at the plasma edge. The diagnostic is sensitive to C III, C IV, and He II intrinsic emission, covering a radial region of 15 cm at the extreme edge of the outboard midplane. Thirteen chords are distributed between toroidal and poloidal views, allowing the toroidal and poloidal rotation and temperature of the plasma edge to be simultaneously measured with 10 … more
Date: August 29, 2003
Creator: Biewer, T. M.; Bell, R. E.; Feder, R.; Johnson, D. W. & Palladino, R. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge, Sol, and Diverter Plasma Turbulence and Macroscopic Transport

Description: In the last few years, it was clearly shown that cross-field transport in the far SOL could be significantly faster than previously thought and that this transport exhibited convective rather then diffusive features. As a result, in high density cases the plasma coming into the SOL from the core recycled at the wall of the tokamak main chamber, rather than flowing into the divertor and recycling there, as the conventional picture of edge plasma flows would suggest. It was also shown that cohere… more
Date: April 25, 2005
Creator: Krasheninnikov, Prof. Sergi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge Turbulence Imaging on NSTX and Alcator C-Mod

Description: Edge turbulence images have been made using an ultra-high speed CCD camera on both NSTX and Alcator C-Mod. In both cases, the D-alpha or HeI (587.6 nm) line emission from localized deuterium or helium gas puffs was viewed along a local magnetic field line near the outer midplane. Fluctuations in this line emission reflect fluctuations in electron density and/or electron temperature through the atomic excitation rates, which can be modeled using the DEGAS-2 code. The 2-D structure of the measure… more
Date: July 10, 2002
Creator: Zweben, S. J.; Maqueda, R. A.; Terry, J. L.; Bai, B.; Boswell, C. J.; Bush, C. E. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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EDGE2D Simulations of JET{sup 13}C Migration Experiments

Description: Material migration has received renewed interest due to tritium retention associated with carbon transport to remote vessel locations. Those results influence the desirability of carbon usage on ITER. Subsequently, additional experiments have been performed, including tracer experiments attempting to identify material migration from specific locations. In this paper, EDGE2D models a well-diagnosed JET{sup 13}C tracer migration experiment. The role of SOL flows upon the migration patterns is ide… more
Date: June 16, 2004
Creator: Strachan, J.D.; Coad, J.P.; Corrigan, G.; Matthews, G.F. & Spence, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Gas Fueling Location on H-mode Access in NSTX

Description: The dependence of H-mode access on the poloidal location of the gas injection source has been investigated in the National Spherical Torus Experiment (NSTX). We find that gas fueling from the center stack midplane area produces the most reproducible H-mode access with generally the lowest L-H threshold power in lower single-null configuration. The edge toroidal rotation velocity is largest (in direction of the plasma current) just before the L-H transition with center stack midplane fueling, an… more
Date: October 9, 2003
Creator: Maingi, R.; Bell, M.; Bell, R.; Biewer, T.; Bush, C.; Chang, C. S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ELMs and the H-mode Pedestal in NSTX

Description: We report on the behavior of ELMs in NBI-heated H-mode plasmas in NSTX. It is observed that the size of Type I ELMs, characterized by the change in plasma energy, decreases with increasing density, as observed at conventional aspect ratio. It is also observed that the Type I ELM size decreases as the plasma equilibrium is shifted from a symmetric double-null toward a lower single-null configuration. Type III ELMs have also been observed in NSTX, as well as a high-performance regime with small E… more
Date: July 16, 2004
Creator: Maingi, R.; Sabbagh, S. A.; Bush, C. E.; Fredrickson, E. D.; Menard, J. E.; Stutman, D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final Technical Report: Global Field Aligned Mesh and Gyrokinetic Field Solver in a Tokamak Edge Geometry

Description: This project was a collaboration between researchers at the California Institute of Technology and the University of California, Irvine to investigate the utility of a global field-aligned mesh and gyrokinetic field solver for simulations of the tokamak plasma edge region. Mesh generation software from UC Irvine was tested with specific tokamak edge magnetic geometry scenarios and the quality of the meshes and the solutions to the gyrokinetic Poisson equation were evaluated.
Date: May 15, 2013
Creator: Cummings, Julian C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The H-mode Pedestal and Edge Localized Modes in NSTX

Description: The research program of the National Spherical Torus Experiment (NSTX) routinely utilizes the H-mode confinement regime to test and extend beta and pulse length limits. As in conventional aspect ratio tokamaks, NSTX observes a variety of edge localized modes (ELMs) in H-mode. Hence a significant part of the research program is dedicated to ELMs studies.
Date: July 16, 2004
Creator: Maingi, R.; Fredrickson, E. D.; Menard, J. E.; Nishino, N.; Roquemore, A. L.; Sabbagh, S. A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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L-H Mode Transitions in the National Spherical Torus Experiment

Description: Edge data from plasmas in the National Spherical Torus Experiment (NSTX) [S. Kaye et al., Fusion Technology 36 (1999) 16] have been compared to theories of transport suppression that have been used to develop a physics framework for low-confinement (L) to high-confinement (H) mode transitions. The NSTX data were obtained in low aspect ratio (R/a approximately equal to 1.3) discharges taken from a variety of discharge phases, including L-modes, L-H transitions, and H-modes with and without edge … more
Date: July 24, 2003
Creator: Kaye, S. M.; Bush, C. E.; Fredrickson, E.; LeBlanc, B.; Maingi, R. & Sabbagh, S. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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H-Mode Turbulence, Power Threshold, ELM, and Pedestal Studies in NSTX

Description: High-confinement mode (H-mode) operation plays a crucial role in NSTX [National Spherical Torus Experiment] research, allowing higher beta limits due to reduced plasma pressure peaking, and long-pulse operation due to high bootstrap current fraction. Here, new results are presented in the areas of edge localized modes (ELMs), H-mode pedestal physics, L-H turbulence, and power threshold studies. ELMs of several other types (as observed in conventional aspect ratio tokamaks) are often observed: (… more
Date: October 28, 2004
Creator: Maingi, R.; Bush, C. E.; Fredrickson, E. D.; Gates, D. A.; Kaye, S. M.; LeBlanc, B. P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heuristic Drift-based Model of the Power Scrape-off width in H-mode Tokamaks

Description: An heuristic model for the plasma scrape-off width in H-mode plasmas is introduced. Grad B and curv B drifts into the SOL are balanced against sonic parallel flows out of the SOL, to the divertor plates. The overall particle flow pattern posited is a modification for open field lines of Pfirsch-Shlüter flows to include sinks to the divertors. These assumptions result in an estimated SOL width of ~ 2aρp/R. They also result in a first-principles calculation of the particle confinement time of H-m… more
Date: April 29, 2011
Creator: Goldston, Robert J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Speed Imaging of Edge Turbulence in NSTX

Description: The two-dimensional radial versus poloidal structure and motion of edge turbulence in NSTX (National Spherical Torus Experiment) were measured by using high-speed imaging of the visible light emission from a localized neutral gas puff. Edge turbulence images are shown and analyzed for Ohmic, L-mode (low-confinement mode) and H-mode (high-confinement mode) plasma conditions. Typical edge turbulence poloidal correlation lengths as measured using this technique are = 4 {+-} 1 cm and autocorrelatio… more
Date: March 2003
Creator: Zweben, S. J.; Maqueda, R.; Stotler, D. P.; Keesee, A.; Boedo, J.; Bush, C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Images of Edge Turbulence in NSTX

Description: The 2-D structure of edge plasma turbulence has been measured in the National Spherical Torus Experiment (NSTX) by viewing the emission of the Da spectral line of deuterium. Images have been made at framing rates of up to 250,000 frames/sec using an ultra-high speed CCD camera developed by Princeton Scientific Instruments. A sequence of images showing the transition between L-mode and H-mode states is shown.
Date: July 16, 2004
Creator: Zweben, S. J.; Bush, C. E.; Maqueda, R.; Munsat, T.; Stotler, D.; Lowrance, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Intermittency in the Scrape-off Layer of the National Spherical Torus Experiment During H-mode Confinement

Description: A gas puff imaging diagnostic is used in the National Spherical Tokamak Experiment [M. Ono, et al., Nucl. Fusion 40, 557 (2000)] to study the edge turbulence and intermittency present during H-mode discharges. In the case of low power Ohmic H-modes the suppression of turbulence/blobs is maintained through the duration of the (short lived) H-modes. Similar quiescent edges are seen during the early stages of H-modes created with the use of neutral beam injection. Nevertheless, as time progresses … more
Date: November 22, 2010
Creator: Maqueda, R. J.; Stotler, D. P. & Zweben, S. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquid Lithium Limiter Experiments in CDX-U

Description: Recent experiments in the Current Drive Experiment-Upgrade provide a first-ever test of large area liquid lithium surfaces as a tokamak first wall, to gain engineering experience with a liquid metal first wall, and to investigate whether very low recycling plasma regimes can be accessed with lithium walls. The CDX-U is a compact (R = 34 cm, a = 22 cm, B{sub toroidal} = 2 kG, I{sub P} = 100 kA, T{sub e}(0) = 100 eV, n{sub e}(0) {approx} 5 x 10{sup 19} m{sup -3}) spherical torus at the Princeton … more
Date: October 28, 2004
Creator: Majeski, R.; Jardin, S.; Kaita, R.; Gray, T.; Marfuta, P.; Spaleta, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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LiWall Fusion - The New Concept of Magnetic Fusion

Description: Utilization of the outstanding abilities of a liquid lithium layer in pumping hydrogen isotopes leads to a new approach to magnetic fusion, called the LiWall Fusion. It relies on innovative plasma regimes with low edge density and high temperature. The approach combines fueling the plasma by neutral injection beams with the best possible elimination of outside neutral gas sources, which cools down the plasma edge. Prevention of cooling the plasma edge suppresses the dominant, temperature gradie… more
Date: January 12, 2011
Creator: Zakharov, L. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MARFE Stability and Movement in an ELMy H-mode NSTX Discharge

Description: The results of a comparison of Multifaceted Asymmetric Radiation From the Edge (MARFE) theory with experiment in the National Spherical Torus Experiment (NSTX) are presented. A variety of MARFE behavior was observed using a fast-framing camera. A basic MARFE theory was applied to NSTX Multi-Pulse Thomson scattering (MPTS) and charge-exchange recombination spectroscopy (CHERS) data. MARFE theory showed some limited agreement with experiment, but uncertainty in the separatrix location constrained… more
Date: February 23, 2009
Creator: F. Kelly, R. Maingi, R. Maqueda, J. Menard, S. Paul
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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