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PISCES and ALT-II: Juelich PSI papers

Description: This publication comprises papers from the PISCES and ALT-II Programs at UCLA which were presented at the International Plasma Surface Interactions Meeting held in Juelich, FRG, on May 2-6, 1988. A list of publications from the PISCES and ALT-II contained in this report are: Deuterium pumping and erosion behavior of selected graphite materials under high flux plasma bombardment in PISCES; Erosion and redeposition behavior of selected NET-candidate materials under high-flux hydrogen, deuterium p… more
Date: August 1, 1988
Creator: Conn, R. W.; Hirooka, Y.; LaBombard, B.; Moyer, R.; Goebel, D. M.; Leung, W. K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of Elm Pulse Propagation in the Diii-D Sol and Divertors With an Ion Convection Model

Description: OAK-B135 Results from dedicated ELM experiments, performed in DIII-D with fast diagnostics to measure the evolution of Type-I ELM effects in the SOL and divertor, are compared with a simple ion convection model and with initial time-dependent UEDGE simulations. Delays between ELM effects observed in the inner versus the outer divertor regions in the experiments scale, as a function of density, with the difference in ion convection time along field lines from the outer midplane to the divertor t… more
Date: August 1, 2003
Creator: Fenstermacher, M. E.; Porter, G. D.; Leonard, A. W.; Brooks, N. H.; Boedo, J. A.; Colchin, R. J. et al.
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Partner: UNT Libraries Government Documents Department
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Recent Experimental Studies of Edge and Internal Transport Barriers in the Diii-D Tokamak

Description: Results from recent experiments on the DIII-D tokamak have revealed many important details on transport barriers at the plasma edge and in the plasma core. These experiments include: (a) the formation of the H-mode edge barrier directly by pellet injection; (b) the formation of a quiescent H-mode edge barrier (QH-mode) which is free from edge localized modes (ELMs), but which still exhibits good density and radiative power control; (c) the formation of multiple transport barriers, such as the q… more
Date: August 1, 2002
Creator: Gohil, P.; Baylor, L. R.; Burrell, K. H.; Casper, T. A.; Doyle, E. J.; Greenfield, C. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An evaluation of kinetic effects in the DIII-D divertor

Description: Under certain conditions, high temperature electrons diffusing across the separatrix near the midplane can propagate to the divertor without collision and produce a high energy tail in the electron distribution function near the separatrix. The authors evaluate a kinetic criterion along the field using measurements from divertor Thomson scattering and compare temperature measurements from target plate Langmuir probes to estimate the magnitude of the high energy tail. A Fokker-Planck kinetic mod… more
Date: August 1, 1998
Creator: Watkins, J. G.; Batishchev, O.; Boedo, J. A.; Lehmer, R.; Moyer, R. A.; Hill, D. N. et al.
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Partner: UNT Libraries Government Documents Department
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SCRAPE-OFF LAYER FEATURES OF THE QH-MODE

Description: The quiescent high confinement (QH-mode) and quiescent double barrier (QDB) modes in DIII-D have long-duration H-mode confinement without ELMs, possibly an alternative operating mode in future tokamaks for avoiding damage by ELMs . Instead of ELMs, there is an edge harmonic oscillation (EHO), which is a continuous electromagnetic mode with associated density fluctuations. The edge pedestal is similar to ELMing H-mode, but at very low density to date. We see C{sup +6} ion temperatures of 3-7 keV… more
Date: August 1, 2002
Creator: Lasnier, C. J.; Burrell, K. H.; Degrassie, J. S.; Leonard, A. W.; Moyer, R. A.; Porter, G. D. et al.
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Partner: UNT Libraries Government Documents Department
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Scaling and profiles of heat flux during partial detachment in DIII-D

Description: The authors examine the scaling of the peak divertor heat flux and total divertor plate power in partially detached divertor (PDD) discharges in DIII-D, as a function of input power and radiated power. The peak divertor heat flux in the attached plasma increases linearly with input power, but saturates in the detached cases. The total divertor plate power remains linear with input power in both the attached and detached plasmas. This is consistent with the fact that the heat flux peak is reduce… more
Date: August 1998
Creator: Lasnier, C. J.; Hill, D. N.; Allen, S. L.; Fenstermacher, M. E.; Porter, G. D.; Leonard, A. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Density H-Mode Discharges with Gas Fueling and Good Confinement on DIII-D

Description: H-mode operation at high density is an attractive regime for future reactor-grade tokamaks [1]. High density maximizes fusion power output while the high confinement of H-mode keeps the plasma energy loss below the alpha heating power. One concern though is the energy released due to individual ELMs must be kept small to protect the diverter target from excess ablation. We report on discharges in DIII-D with electron densities as high as 1.45 times the Greenwald density, n{sub GW}(10{sup 20}m{s… more
Date: August 1, 2000
Creator: Leonard, A. W.; Osborne, T. H.; Mahdavi, M. A.; Fenstermacher, M. E.; Lasnier, C. J.; Petrie, T. W. et al.
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Partner: UNT Libraries Government Documents Department
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Interpretive Modeling of Simple-as-Possible-Plasma Discharges on Diii-D Using the Oedge Code

Description: Recently a number of major, unanticipated effects have been reported in tokamak edge research raising the question of whether we understand the controlling physics of the edge. This report is on the first part--here focused on the outer divertor--of a systematic study of the simplest possible edge plasma--no ELMs, no detachment, etc.--for a set of 10 repeat, highly-diagnosed, single-null, divertor discharges in DIII-D. For almost the entire, extensive data set so far evaluated, the matches of e… more
Date: August 1, 2002
Creator: Stangby, P. C.; Elder, J. D.; Boedo, J. A.; Bray, B.; Brooks, N. H.; Fenstermacher, M. E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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