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in creator/contributor: "Krasheninnikov, S."  
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Migration of Artificially Introduced Micron Size Carbon Dust in the DIII-D Divertor

Description: Migration of pre-characterized carbon dust in a tokamak environment was studied by introducing about 30 milligrams of dust flakes 5-10 {micro}m in diameter in the lower divertor of DIII-D using the DiMES sample holder. The dust was exposed to high power ELMing Hmode discharges in lower-single-null magnetic configuration with the strike points swept across the divertor floor. When the outer strike point (OSP) passed over the dust holder exposing it to high particle and heat fluxes, part of the d… more
Date: May 15, 2006
Creator: Rudakov, D.; West, W.; Wong, C.; Brooks, N.; Evans, T.; Fenstermacher, M. et al.
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Partner: UNT Libraries Government Documents Department
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Dust Measurements in Tokamaks

Description: Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd… more
Date: April 23, 2008
Creator: Rudakov, D.; Yu, J.; Boedo, J.; Hollmann, E.; Krasheninnikov, S.; Moyer, R. et al.
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Partner: UNT Libraries Government Documents Department
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Large plasma pressure perturbations and radial convective transport in a tokamak

Description: Strongly localized plasma structures with large pressure inhomogeneities (such as plasma blobs in the scrape-off-layer (SOL)/shadow regions, pellet clouds, ELMs) observed in the tokamaks, stellarators and linear plasma devices. Experimental studies of these phenomena reveal striking similarities including more convective rather than diffusive radial plasma transport. We suggest that rather simple models can describe many essentials of blobs, ELMs, and pellet clouds dynamics. The main ingredient… more
Date: February 4, 2004
Creator: Krasheninnikov, S.; Ryutov, D. & Yu, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of Issues in U.S. Edge-Plasma Research and Priority Topics for the Next Five Years

Description: The Edge Coordinating Committee (ECC) was formed in July 14-15, 2004 when OFES Theory Team invited 14 plasma researchers to a two-day meeting in Germantown, MD to discuss the state of edge-plasma research in the U.S. with a focus on theory and modeling (see http://www.mfescience.org/ecc/ ecc/). At that time, OFES tasked the ECC with providing, in about a six month period, a report on the present status of key issues in this area together with a roadmap of what range of activities should be unde… more
Date: March 16, 2005
Creator: Bateman, G.; Chang, C.; Fenstermacher, M.; Guzdar, P.; Hahm, T. S.; Krasheninnikov, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transport by Intermittency in the Boundary of the Diii-D Tokamak

Description: A271 TRANSPORT BY INTERMITTENCY IN THE BOUNDARY OF THE DIII-D TOKAMAK. Intermittent plasma objectives (IPOs) featuring higher pressure than the surrounding plasma, are responsible for {approx} 50% of the E x B{sub T} radial transport in the scrape off layer (SOL) of the DIII-D tokamak in L- and H-mode discharges. Conditional averaging reveals that the IPOs are positively charged and feature internal poloidal electric fields of up to 4000 V/m. The IPOs move radially with E x B{sub T}/B{sup 2} ve… more
Date: November 1, 2002
Creator: Boedo, J. A.; Rudakov, D. L.; Moyer, R. A.; Mckee, G. R.; Colchin, R. J.; Schaffer, M. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Intermittent Convection in the Boundary of DIII-D

Description: Intermittent plasma objects (IPOs) featuring higher pressure than the surrounding plasma, and responsible for {approx}50% of the E x B{sub T} radial transport, are observed in the scrape-off layer (SOL) and edge of the DIII-D tokamak. The skewness of probe and BES intermittent data suggest IPO formation at or near the last closed flux surface (LCFS) and the existence of hole-IPO pairs. The particle content of the IPOs at the LCFS is linearly dependent on the discharge density, however, when nor… more
Date: June 1, 2002
Creator: Boedo, J. A.; Rudakov, D. L.; Colchin, R. J.; Moyer, R. A.; Krasheninnikov, S.; Whyte, D. G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status and Plans for the National Spherical Torus Experimental Research Facility

Description: An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at high beta, non-inductive sustainment, solenoid-free start-up, and power and particle handling. I… more
Date: July 27, 2005
Creator: Columbia University
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continuum Edge Gyrokinetic Theory and Simulations

Description: The following results are presented from the development and application of TEMPEST, a fully nonlinear (full-f) five dimensional (3d2v) gyrokinetic continuum edge-plasma code. (1) As a test of the interaction of collisions and parallel streaming, TEMPEST is compared with published analytic and numerical results for endloss of particles confined by combined electrostatic and magnetic wells. Good agreement is found over a wide range of collisionality, confining potential, and mirror ratio; and th… more
Date: January 9, 2007
Creator: Xu, X. Q.; Xiong, Z.; Dorr, M. R.; Hittinger, J. A.; Bodi, K.; Candy, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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