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Sample records for torus experiment nstx

  1. Status of the control system on the National Spherical Torus Experiment (NSTX)

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    #61 final Status of the control system on the National Spherical Torus Experiment (NSTX) D. A Abstract In 2003, the NSTX plasma control system was used for plasma shape control using real. More recently, the system has been upgraded to support feedback control of the resistive wall mode (RWM

  2. National Spherical Torus Experiment (NSTX) Power Supply Real Time Controller

    E-Print Network [OSTI]

    . The NSTX depends on a real time, high speed, synchronous, and deterministic control system isolated from each other but subject to the same "Firing Generator" (FG). Each PSS Magnets Power Supply

  3. Approval of CD-2 for the National Spherical Torus Experiment (NSTX) Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    of compact and high normalized pressure "spherical torus" (ST) magnetic fusion plasmas. The compact Plasma Physics Laboratory DOE Princeton Site Office (SSO) Office of Science Office of Fusion Energy Selection and Cost Range for the NSTX Upgrade Project was approved by the Associate Director for Fusion

  4. (NATIONAL SPHERICAL TORUS EXPERIMENT) STRUCTURAL DESIGN CRITERIA

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX (NATIONAL SPHERICAL TORUS EXPERIMENT) STRUCTURAL DESIGN CRITERIA NSTX-CRIT-0001-01 February Design Criteria Revision 1 RECORD OF REVISIONS REVISION DATE ECP DESCRIPTION OF CHANGE 0 AUGUST 2003. STRUCTURAL CRITERIA

  5. Vessel Eddy Current Measurement for the National Spherical Torus Experiment (NSTX)

    SciTech Connect (OSTI)

    D.A. Gates; J. Menard; R. Marsala

    2004-11-19

    A simple analog circuit that measures the NSTX axisymmetric eddy current distribution has been designed and constructed. It is based on simple circuit model of the NSTX vacuum vessel that was calibrated using a special axisymmetric eddy current code which was written so that accuracy was maintained in the vicinity of the current filaments. The measurement and the model have been benchmarked against data from numerous vacuum shots and they are in excellent agreement. This is an important measurement that helps give more accurate equilibrium reconstructions.

  6. Abs t rac t ---The National Spherical Torus Experiment (NSTX) is a low aspect ratio s ph e r i c a l

    E-Print Network [OSTI]

    , and initial power tests were completed in February o f 1 9 9 9 . The majority of the design and c on s t r u c. The Centerstack Assembly consists of the i nn e r legs of the Toroidal Field (TF) windings, t h e Ohmic Heating issues associated with the design, fabrication and assembly of the NSTX Torus system i nc l ud i ng those

  7. Vessel eddy current measurement for the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Gates, D.A.; Menard, J.E.; Marsala, R.J. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States)

    2004-12-01

    A simple analog circuit that measures the National Spherical Torus Experiment (NSTX) axisymmetric eddy current distribution has been designed and constructed. It is based on simple circuit model of the NSTX vacuum vessel that was calibrated using a special axisymmetric eddy current code which was written so that accuracy was maintained in the vicinity of the current filaments [J. Menard, J. Fusion Tech. (to be published)]. The measurement and the model have been benchmarked against data from numerous vacuum shots and they are in excellent agreement. This is an important measurement that helps give more accurate equilibrium reconstructions.

  8. Characteristics of Energy Transport of Li-conditioned and non-Li-conditioned Plasmas in the National Spherical Torus Experiment (NSTX)

    SciTech Connect (OSTI)

    Ding, S.; Kaye, S. M.; Bell, R. E.; Kaita, R.; Kugel, H.; LeBlanc, B. P.; Paul, S.; Wan, B.

    2009-10-21

    The transport properties of NSTX plasmas obtained during the 2008 experimental cam- paign have been studied and are reported here. Transport trends and dependences have been isolated, and it is found that both electron and ion energy transport coefficients have strong dependences on local values of n?T, which in turn is strongly dependent on local current density profile. Without identifying this dependence, it is difficult to identify others, such as the dependence of transport coefficients on Bp (or q), Ip and Pheat. In addition, a comparison between discharges with and without Lithium wall conditioning has been made. While the trends in the two sets of data are similar, the thermal transport loss, especially in the electron channel, is found to strongly depend on the amount of Lithium deposited, decreasing by up to 50% of its no-Lithium value.

  9. Electron Bernstein Wave Research on the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    G. Taylor; A. Bers; T.S. Bigelow; M.D. Carter; J.B. Caughman; J. Decker; S. Diem; P.C. Efthimion; N.M. Ershov; E. Fredd; R.W. Harvey; J. Hosea; F. Jaeger; J. Preinhaelter; A.K. Ram; D.A. Rasmussen; A.P. Smirnov; J.B. Wilgen; J.R. Wilson

    2005-04-21

    Off-axis electron Bernstein wave current drive (EBWCD) may be critical for sustaining noninductive high-beta National Spherical Torus Experiment (NSTX) plasmas. Numerical modeling results predict that the {approx}100 kA of off-axis current needed to stabilize a solenoid-free high-beta NSTX plasma could be generated via Ohkawa current drive with 3 MW of 28 GHz EBW power. In addition, synergy between EBWCD and bootstrap current may result in a 10% enhancement in current-drive efficiency with 4 MW of EBW power. Recent dual-polarization EBW radiometry measurements on NSTX confirm that efficient coupling to EBWs can be readily accomplished by launching elliptically polarized electromagnetic waves oblique to the confining magnetic field, in agreement with numerical modeling. Plans are being developed for implementing a 1 MW, 28 GHz proof-of-principle EBWCD system on NSTX to test the EBW coupling, heating and current-drive physics at high radio-frequency power densities.

  10. M. Ono, NSTX 1 National Spherical Torus Experiment (NSTX)*

    E-Print Network [OSTI]

    . The NBI heating system and associated NBI based diagnostics such as the CHERS will be operational in Oct.5, and plasma pulse length of up to 5 sec. The plasma heating / current drive (CD) tools are High Harmonic Fast device is shown in Fig. 1. The device mid­plane is about 3.5 m from the floor. The device center

  11. Divertor Heat Flux Mitigation in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Soukhanovskii, V A; Maingi, R; Gates, D A; Menard, J E; Paul, S F; Raman, R; Roquemore, A L; Bell, M G; Bell, R E; Boedo, J A; Bush, C E; Kaita, R; Kugel, H W; LeBlanc, B P; Mueller, D

    2008-08-04

    Steady-state handling of divertor heat flux is a critical issue for both ITER and spherical torus-based devices with compact high power density divertors. Significant reduction of heat flux to the divertor plate has been achieved simultaneously with favorable core and pedestal confinement and stability properties in a highly-shaped lower single null configuration in the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 2000] using high magnetic flux expansion at the divertor strike point and the radiative divertor technique. A partial detachment of the outer strike point was achieved with divertor deuterium injection leading to peak flux reduction from 4-6 MW m{sup -2} to 0.5-2 MW m{sup -2} in small-ELM 0.8-1.0 MA, 4-6 MW neutral beam injection-heated H-mode discharges. A self-consistent picture of outer strike point partial detachment was evident from divertor heat flux profiles and recombination, particle flux and neutral pressure measurements. Analytic scrape-off layer parallel transport models were used for interpretation of NSTX detachment experiments. The modeling showed that the observed peak heat flux reduction and detachment are possible with high radiated power and momentum loss fractions, achievable with divertor gas injection, and nearly impossible to achieve with main electron density, divertor neutral density or recombination increases alone.

  12. Simulation of microtearing turbulence in national spherical torus experiment

    SciTech Connect (OSTI)

    Guttenfelder, W.; Kaye, S. M.; Bell, R. E.; Hammett, G. W.; LeBlanc, B. P.; Mikkelsen, D. R.; Ren, Y.; Candy, J.; Nevins, W. M.; Wang, E.; Zhang, J.; Crocker, N. A.; Yuh, H.

    2012-05-15

    Thermal energy confinement times in National Spherical Torus Experiment (NSTX) dimensionless parameter scans increase with decreasing collisionality. While ion thermal transport is neoclassical, the source of anomalous electron thermal transport in these discharges remains unclear, leading to considerable uncertainty when extrapolating to future spherical tokamak (ST) devices at much lower collisionality. Linear gyrokinetic simulations find microtearing modes to be unstable in high collisionality discharges. First non-linear gyrokinetic simulations of microtearing turbulence in NSTX show they can yield experimental levels of transport. Magnetic flutter is responsible for almost all the transport ({approx}98%), perturbed field line trajectories are globally stochastic, and a test particle stochastic transport model agrees to within 25% of the simulated transport. Most significantly, microtearing transport is predicted to increase with electron collisionality, consistent with the observed NSTX confinement scaling. While this suggests microtearing modes may be the source of electron thermal transport, the predictions are also very sensitive to electron temperature gradient, indicating the scaling of the instability threshold is important. In addition, microtearing turbulence is susceptible to suppression via sheared E Multiplication-Sign B flows as experimental values of E Multiplication-Sign B shear (comparable to the linear growth rates) dramatically reduce the transport below experimental values. Refinements in numerical resolution and physics model assumptions are expected to minimize the apparent discrepancy. In cases where the predicted transport is strong, calculations suggest that a proposed polarimetry diagnostic may be sensitive to the magnetic perturbations associated with the unique structure of microtearing turbulence.

  13. Modification Of The Electron Energy Distribution Function During Lithium Experiments On The National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Jaworski, M A; Gray, T K; Kaita, R; Kallman, J; Kugel, H; LeBlanc, B; McLean, A; Sabbagh, S A; Soukanovskii, V; Stotler, D P

    2011-06-03

    The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX.

  14. New Capabilities and Results for the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    M.G. Bell, R.E. Bell, D.A. Gates, S.M. Kaye, H. Kugel, B.P. LeBlanc, F.M. Levinton, R. Maingi, J.E. Menard, R. Raman, S.A. Sabbagh, D. Stutman and the NSTX Research Team

    2008-02-29

    The National Spherical Torus Experiment (NSTX) produces plasmas with toroidal aspect ratio as low as 1.25, which can be heated by up to 6 MW High-Harmonic Fast Waves and up to 7 MW of deuterium Neutral Beam Injection. Using new poloidal fields coils, plasmas with cross-section elongation up to 2.7, triangularity 0.8, plasma currents Ip up to 1.5 MA and normalized currents Ip/a?BT up to 7.5 MA/m?T have been achieved. A significant extension of the plasma pulse length, to 1.5 s at a plasma current of 0.7 MA, has been achieved by exploiting the bootstrap and NBI-driven currents to reduce the dissipation of poloidal flux. Inductive plasma startup has been supplemented by Coaxial Helicity Injection (CHI) and the production of persistent current on closed flux surfaces by CHI has now been demonstrated in NSTX. The plasma response to magnetic field perturbations with toroidal mode numbers n = 1 or 3 and the effects on the plasma rotation have been investigated using three pairs of coils outside the vacuum vessel. Recent studies of both MHD stability and of transport benefitted from improved diagnostics, including measurements of the internal poloidal field using the motional Stark effect (MSE). In plasmas with a region of reversed magnetic shear in the core, now confirmed by the MSE data, improved electron confinement has been observed.

  15. Hardwired Control Changes For NSTX DC Power Feeds

    SciTech Connect (OSTI)

    Ramakrishnan, S.

    2013-06-28

    The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The original TFTR Hardwired Control System (HCS) with electromechanical relays was used for NSTX DC Power loop control and protection during NSTX operations. As part of the NSTX Upgrade, the HCS is being changed to a PLC-based system with the same control logic. This paper gives a description of the changeover to the new PLC-based system __________________________________________________

  16. NSTX-U Digital Coil Protection System Software Detailed Design

    SciTech Connect (OSTI)

    2014-06-01

    The National Spherical Torus Experiment (NSTX) currently uses a collection of analog signal processing solutions for coil protection. Part of the NSTX Upgrade (NSTX-U) entails replacing these analog systems with a software solution running on a conventional computing platform. The new Digital Coil Protection System (DCPS) will replace the old systems entirely, while also providing an extensible framework that allows adding new functionality as desired.

  17. A Megawatt-level 28z GHz Heating System For The National Spherical Torus Experiment Upgrade

    SciTech Connect (OSTI)

    Taylor, Gary

    2014-04-01

    The National Spherical Torus Experiment Upgrade (NSTX-U) will operate at axial toroidal fields of < 1 T and plasma currents, Ip < 2 MA. The development of non-inductive (NI) plasmas is a major long-term research goal for NSTX-U. Time dependent numerical simulations of 28 GHz electron cyclotron (EC) heating of low density NI start-up plasmas generated by Coaxial Helicity Injection (CHI) in NSTX-U predict a significant and rapid increase of the central electron temperature (Te(0)) before the plasma becomes overdense. The increased Te(0) will significantly reduce the Ip decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. A megawatt-level, 28 GHz electron heating system is planned for heating NI start-up plasmas in NSTX-U. In addition to EC heating of CHI start-up discharges, this system will be used for electron Bernstein wave (EBW) plasma start-up, and eventually for EBW heating and current drive during the Ip flattop.

  18. Imaging x-ray crystal spectrometers for the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Bitter, M.; Hill, K.W.; Roquemore, A.L.; Beiersdorfer, P.; Kahn, S.M.; Elliott, S.R.; Fraenkel, B.

    1999-01-01

    A new type of high-resolution x-ray imaging crystal spectrometers is described for implementation on the National Spherical Torus Experiment (NSTX) to provide spatially and temporally resolved data on the ion temperature, toroidal and poloidal plasma rotation, electron temperature, impurity ion-charge state distributions, and impurity transport. These data are derived from observations of the satellite spectra of heliumlike argon, ArthinspXVII, which is the dominant charge state for electron temperatures in the range from 0.4 to 3.0 keV and which is accessible to NSTX. Experiments at the Torus Experiment for Technology Oriented Research (TEXTOR) demonstrate that a throughput of 2{times}10{sup 5}thinspphotons/s (corresponding to the count-rate limit of the present detectors) can easily be obtained with small, nonperturbing argon gas puffs of less than 1{times}10{sup {minus}3}thinspTorrthinspscr(l)/s, so that it is possible to record spectra with a small statistical error and a good time resolution (typically 50 and 1 ms in some cases). Employing a novel design, which is based on the imaging properties of spherically bent crystals, the spectrometers will provide spectrally and spatially resolved images of the plasma for all experimental conditions, which include ohmically heated discharges as well as plasmas with rf and neutral-beam heating. The conceptual design, experimental results on the focusing properties, and relevant spectral data from TEXTOR are presented. {copyright} {ital 1999 American Institute of Physics.}

  19. Ohmic Flux Consumption During Initial Operation of the NSTX Spherical Torus

    E-Print Network [OSTI]

    been achieved on NSTX, while faster ramps generate significant MHD activity. Discharges with IP will rely on OH current drive to generate target plasmas suitable for strong auxiliary heating to test.5, vacuum toroidal field B T = 0.3 Tesla at R 0 , plasma current I P

  20. Progress in Understanding Error-field Physics in NSTX Spherical Torus Plasmas

    SciTech Connect (OSTI)

    E. Menard, R.E. Bell, D.A. Gates, S.P. Gerhardt, J.-K. Park, S.A. Sabbagh, J.W. Berkery, A. Egan, J. Kallman, S.M. Kaye, B. LeBlanc, Y.Q. Liu, A. Sontag, D. Swanson, H. Yuh, W. Zhu and the NSTX Research Team

    2010-05-19

    The low aspect ratio, low magnetic field, and wide range of plasma beta of NSTX plasmas provide new insight into the origins and effects of magnetic field errors. An extensive array of magnetic sensors has been used to analyze error fields, to measure error field amplification, and to detect resistive wall modes in real time. The measured normalized error-field threshold for the onset of locked modes shows a linear scaling with plasma density, a weak to inverse dependence on toroidal field, and a positive scaling with magnetic shear. These results extrapolate to a favorable error field threshold for ITER. For these low-beta locked-mode plasmas, perturbed equilibrium calculations find that the plasma response must be included to explain the empirically determined optimal correction of NSTX error fields. In high-beta NSTX plasmas exceeding the n=1 no-wall stability limit where the RWM is stabilized by plasma rotation, active suppression of n=1 amplified error fields and the correction of recently discovered intrinsic n=3 error fields have led to sustained high rotation and record durations free of low-frequency core MHD activity. For sustained rotational stabilization of the n=1 RWM, both the rotation threshold and magnitude of the amplification are important. At fixed normalized dissipation, kinetic damping models predict rotation thresholds for RWM stabilization to scale nearly linearly with particle orbit frequency. Studies for NSTX find that orbit frequencies computed in general geometry can deviate significantly from those computed in the high aspect ratio and circular plasma cross-section limit, and these differences can strongly influence the predicted RWM stability. The measured and predicted RWM stability is found to be very sensitive to the E × B rotation profile near the plasma edge, and the measured critical rotation for the RWM is approximately a factor of two higher than predicted by the MARS-F code using the semi-kinetic damping model.

  1. National Spherical Torus Experiment NSTX CENTER STACK UPGRADE

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ; added section 2.6 "Design Criteria"; added 3.1.3.3 "Center Stack Assembly"; 3.1.3.4 "Coil Bus Runs 2.5 Field Errors 14 2.6 Design Criteria 14 2.6.1 General Design Guidelines 14 2.6.2 Failure Modes and Effects Analysis (FMEA) 15 2.6.3 Structural Design Criteria 15 2.7 Material

  2. National Spherical Torus Experiment NSTX CENTER STACK UPGRADE

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Analysis (FMEA) 14 2.6.3 Structural Design Criteria 15 2.7 Material Selection 15 2.8 General Electrical

  3. National Spherical Torus Experiment (NSTX) Power Supply Real Time Controller

    E-Print Network [OSTI]

    depends on a real time, high speed, synchronous, and deterministic control system acting on a system Generator" (FG). Each PSS Magnets Power Supply System Plasma Power Supply Real Time Control Plasma Real Time

  4. PPPL-3445 PPPL-3445 National Spherical Torus Experiment (NSTX)

    E-Print Network [OSTI]

    in Calendar Year 2000. The home page for PPPL Reports and Publications is: http://www.pppl.gov/pub_report/ DOE-term applications such as the Volume Neutron Source (VNS) and burning plasmas, and future applications to the plasma. The NBI heating system and associated NBI based diagnostics such as the CHERS will be operational

  5. National Spherical Torus Experiment (NSTX) | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework usesofPublications TheScience (SC)ResourceScience » NSS

  6. Electron Bernstein Wave Research on NSTX and CDX-U

    SciTech Connect (OSTI)

    G. Taylor; P.C. Efthimion; B. Jones; G.L. Bell; A. Bers; T.S. Bigelow; M.D. Carter; R.W. Harvey; A.K. Ram; D.A. Rasmussen; A.P. Smirnov; J.B. Wilgen; J.R. Wilson

    2003-06-10

    Studies of thermally emitted electron Bernstein waves (EBWs) on CDX-U and NSTX, via mode conversion (MC) to electromagnetic radiation, support the use of EBWs to measure the Te profile and provide local electron heating and current drive (CD) in overdense spherical torus plasmas. An X-mode antenna with radially adjustable limiters successfully controlled EBW MC on CDX-U and enhanced MC efficiency to {approx} 100%. So far the X-mode MC efficiency on NSTX has been increased by a similar technique to 40-50% and future experiments are focused on achieving * 80% MC. MC efficiencies on both machines agree well with theoretical predictions. Ray tracing and Fokker-Planck modeling for NSTX equilibria are being conducted to support the design of a 3 MW, 15 GHz EBW heating and CD system for NSTX to assist non-inductive plasma startup, current ramp up, and to provide local electron heating and CD in high beta NSTX plasmas.

  7. Full wave simulations of fast wave heating losses in the scrape-off layer of NSTX and NSTX-U

    SciTech Connect (OSTI)

    Bertelli, Nicola [Princeton Plasma Physics Laboratory (PPPL); Jaeger, E. F. [XCEL; Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Berry, Lee Alan [XCEL Engineering Inc., Oak Ridge; Gerhardt, S. [Princeton Plasma Physics Laboratory (PPPL); Green, David L [ORNL; LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Perkins, R. J. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Valeo, E. J. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)

    2014-01-01

    Full wave simulations of fusion plasmas show a direct correlation between the location of the fast-wave cut-off, radiofrequency (RF) field amplitude in the scrape-off layer (SOL) and the RF power losses in the SOL observed in the National Spherical Torus eXperiment (NSTX). In particular, the RF power losses in the SOL increase significantly when the launched waves transition from evanescent to propagating in that region. Subsequently, a large amplitude electric field occurs in the SOL, driving RF power losses when a proxy collisional loss term is added. A 3D reconstruction of absorbed power in the SOL is presented showing agreement with the RF experiments in NSTX. Loss predictions for the future experiment NSTX-Upgrade (NSTX-U) are also obtained and discussed.

  8. Ramp-up of CHI Initiated Plasmas on NSTX

    SciTech Connect (OSTI)

    Mueller, D; Bell, R E; LeBlanc, B; Roquemore, A L; Raman, R; Jarboe, T R; Nelson, B A

    2009-10-29

    Experiments on the National Spherical Torus (NSTX) have now demonstrated flux savings using transient coaxial helicity injection (CHI). In these discharges, the discharges initiated by CHI are ramped up with an inductive transformer and exhibit higher plasma current than discharges without the benefit of CHI initiation.

  9. Primary ELM filament structure in the National Spherical Torus Experiment

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Primary ELM filament structure in the National Spherical Torus Experiment R. J. Maqueda,1 R. Maingi modes give rise to plasma filaments that burst radially outward during the non-linear phase to study the evolution and characteristics of the post-ELM filaments. These edge filaments, which are well

  10. Using LGI experiments to achieve better understanding of pedestal-edge coupling in NSTX-U

    SciTech Connect (OSTI)

    Wang, Zhehui

    2015-02-23

    PowerPoint presentation. Latest advances in granule or dust injection technologies, fast and high-resolution imaging, together with micro-/nano-structured material fabrication, provide new opportunities to examine plasma-material interaction (PMI) in magnetic fusion environment. Some of our previous work in these areas is summarized. The upcoming LGI experiments in NSTX-U will shed new light on granular matter transport in the pedestal-edge region. In addition to particle control, these results can also be used for code validation and achieving better understanding of pedestal-edge coupling in fusion plasmas in both NSTX-U and others.

  11. Design of solid state neutral particle analyzer array for National Spherical Torus Experiment-Upgrade

    SciTech Connect (OSTI)

    Liu, D., E-mail: deyongl@uci.edu; Heidbrink, W. W.; Zhu, Y. B. [Department of Physics and Astronomy, University of California - Irvine, Irvine, California 92697 (United States); Tritz, K. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Roquemore, A. L.; Medley, S. S. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-11-15

    A new compact, multi-channel Solid State Neutral Particle Analyzer (SSNPA) diagnostic based on silicon photodiode array has been designed and is being fabricated for the National Spherical Torus Experiment-Upgrade (NSTX-U). The SSNPA system utilizes a set of vertically stacked photodiode arrays in current mode viewing the same plasma region with different filter thickness to obtain fast temporal resolution (?120 kHz bandwidth) and coarse energy information in three bands of >25?keV, >45 keV, and >65 keV. The SSNPA system consists of 15 radial sightlines that intersect existing on-axis neutral beams at major radii between 90 and 130 cm, 15 tangential sightlines that intersect new off-axis neutral beams at major radii between 120 and 145 cm. These two subsystems aim at separating the response of passing and trapped fast ions. In addition, one photodiode array whose viewing area does not intersect any neutral beams is used to monitor passive signals produced by fast ions that charge exchange with background neutrals.

  12. Direct X-B mode conversion for high-? national spherical torus experiment in nonlinear regime

    SciTech Connect (OSTI)

    Ali Asgarian, M. E-mail: maa@msu.edu; Parvazian, A.; Abbasi, M.; Verboncoeur, J. P.

    2014-09-15

    Electron Bernstein wave (EBW) can be effective for heating and driving currents in spherical tokamak plasmas. Power can be coupled to EBW via mode conversion of the extraordinary (X) mode wave. The most common and successful approach to study the conditions for optimized mode conversion to EBW was evaluated analytically and numerically using a cold plasma model and an approximate kinetic model. The major drawback in using radio frequency waves was the lack of continuous wave sources at very high frequencies (above the electron plasma frequency), which has been addressed. A future milestone is to approach high power regime, where the nonlinear effects become significant, exceeding the limits of validity for present linear theory. Therefore, one appropriate tool would be particle in cell (PIC) simulation. The PIC method retains most of the nonlinear physics without approximations. In this work, we study the direct X-B mode conversion process stages using PIC method for incident wave frequency f{sub 0}?=?15?GHz, and maximum amplitude E{sub 0}?=?10{sup 5?}V/m in the national spherical torus experiment (NSTX). The modelling shows a considerable reduction in X-B mode conversion efficiency, C{sub modelling}?=?0.43, due to the presence of nonlinearities. Comparison of system properties to the linear state reveals predominant nonlinear effects; EBW wavelength and group velocity in comparison with linear regime exhibit an increment around ?36% and 17%, respectively.

  13. November 10, 1998 Physics Design of the National Spherical Torus

    E-Print Network [OSTI]

    1 Abstract The mission of the National Spherical Torus Experiment (NSTX) is to prove the principles an attractive path to a reactor or Volumetric Neutron Source (VNS). The ST fusion core would be small, economic and is presently under construction. Various reactor concepts have been advanced for the ST, 7,8 and these have

  14. Analysis Efforts Supporting NSTX Upgrades

    SciTech Connect (OSTI)

    H.Zhang, P. Titus, P. Rogoff, A.Zolfaghari, D. Mangra, M. Smith

    2010-11-29

    The National Spherical Torus Experiment (NSTX) is a low aspect ratio, spherical torus (ST) configuration device which is located at Princeton Plasma Physics Laboratory (PPPL) This device is presently being updated to enhance its physics by doubling the TF field to 1 Tesla and increasing the plasma current to 2 Mega-amperes. The upgrades include a replacement of the centerstack and addition of a second neutral beam. The upgrade analyses have two missions. The first is to support design of new components, principally the centerstack, the second is to qualify existing NSTX components for higher loads, which will increase by a factor of four. Cost efficiency was a design goal for new equipment qualification, and reanalysis of the existing components. Showing that older components can sustain the increased loads has been a challenging effort in which designs had to be developed that would limit loading on weaker components, and would minimize the extent of modifications needed. Two areas representing this effort have been chosen to describe in more details: analysis of the current distribution in the new TF inner legs, and, second, analysis of the out-of-plane support of the existing TF outer legs.

  15. Power Supply Changes for NSTX Resistive Wall Mode Coils

    SciTech Connect (OSTI)

    Ramakrishnan, S S.

    2013-06-28

    The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. Prior to 2004, the NSTX power system was feeding twelve (12) circuits in the machine. In 2004 the Resistive Wall Mode (RWM) Coils were installed on the machine to correct error fields. There are six of these coils installed around the machine in the mid-plane. Since these coils need fast and accurate controls, a Switching Power Amplifier (SPA) with three sub-units was procured, installed and commissioned along with other power loop components. Two RWM Coils were connected in series and fed from one SPA sub-unit. After the initial RWM campaign, operational requirements evolved such that each of the RWM coils now requires separate power and control. Hence a second SPA with three sub-units has been procured and installed. The second unit is of improved design and has the controls and power components completely isolated. The existing thyristor rectifier is used as DC Link to both of the Switching Power Amplifiers. The controls for the RWM are integrated into the overall computer control of the DC Power systems for NSTX. This paper describes the design changes in the RWM Power system for NSTX.

  16. Measured improvement of global magnetohydrodynamic mode stability at high-beta, and in reduced collisionality spherical torus plasmas

    SciTech Connect (OSTI)

    Berkery, J. W.; Sabbagh, S. A.; Balbaky, A.; Bell, R. E.; Diallo, A.; Gerhardt, S. P.; LeBlanc, B. P.; Manickam, J.; Menard, J. E.; Podestà, M.; Betti, R.

    2014-05-15

    Global mode stability is studied in high-? National Spherical Torus Experiment (NSTX) plasmas to avoid disruptions. Dedicated experiments in NSTX using low frequency active magnetohydrodynamic spectroscopy of applied rotating n?=?1 magnetic fields revealed key dependencies of stability on plasma parameters. Observations from previous NSTX resistive wall mode (RWM) active control experiments and the wider NSTX disruption database indicated that the highest ?{sub N} plasmas were not the least stable. Significantly, here, stability was measured to increase at ?{sub N}?l{sub i} higher than the point where disruptions were found. This favorable behavior is shown to correlate with kinetic stability rotational resonances, and an experimentally determined range of measured E?×?B frequency with improved stability is identified. Stable plasmas appear to benefit further from reduced collisionality, in agreement with expectation from kinetic RWM stabilization theory, but low collisionality plasmas are also susceptible to sudden instability when kinetic profiles change.

  17. Overview of the physics and engineering design of NSTX upgrade

    SciTech Connect (OSTI)

    Menard, J. E. [Princeton Plasma Physics Laboratory (PPPL); Gerhardt, S. P. [Princeton Plasma Physics Laboratory (PPPL); Bell, M. [Princeton Plasma Physics Laboratory (PPPL); Bialek, J [Columbia University; Brooks, A. [Princeton Plasma Physics Laboratory (PPPL); Canik, John [ORNL; Chrzanowski, J. [Princeton Plasma Physics Laboratory (PPPL); Denault, M [Princeton Plasma Physics Laboratory (PPPL)

    2012-01-01

    The spherical tokamak (ST) is a leading candidate for a Fusion Nuclear Science Facility (FNSF) due to its compact size and modular configuration. The National Spherical Torus eXperiment (NSTX) is a MA-class ST facility in the US actively developing the physics basis for an ST-based FNSF. In plasma transport research, ST experiments exhibit a strong (nearly inverse) scaling of normalized confinement with collisionality, and if this trend holds at low collisionality, high fusion neutron fluences could be achievable in very compact ST devices. A major motivation for the NSTX Upgrade (NSTX-U) is to span the next factor of 3-6 reduction in collisionality. To achieve this collisionality reduction with equilibrated profiles, NSTX-U will double the toroidal field, plasma current, and NBI heating power and increase the pulse length from 1-1.5 s to 5-8 s. In the area of stability and advanced scenarios, plasmas with higher aspect ratio and elongation, high beta(N), and broad current profiles approaching those of an ST-based FNSF have been produced in NSTX using active control of the plasma beta and advanced resistive wall mode control. High non-inductive current fractions of 70% have been sustained for many current diffusion times, and the more tangential injection of the 2nd NBI of the Upgrade is projected to increase the NBI current drive by up to a factor of 2 and support 100% non-inductive operation. More tangential NBI injection is also projected to provide non-solenoidal current ramp-up as needed for an ST-based FNSF. In boundary physics, NSTX measures an inverse relationship between the scrape-off layer heat-flux width and plasma current that could unfavourably impact next-step devices. Recently, NSTX has successfully demonstrated substantial heat-flux reduction using a snowflake divertor configuration, and this type of divertor is incorporated in the NSTX-U design. The physics and engineering design supporting NSTX Upgrade is described.

  18. NSTX Diagnostics for Fusion Plasma Science Studies

    SciTech Connect (OSTI)

    R. Kaita; D. Johnson; L. Roquemore; M. Bitter; F. Levinton; F. Paoletti; D. Stutman; and the NSTX Team

    2001-07-05

    This paper will discuss how plasma science issues are addressed by the diagnostics for the National Spherical Torus Experiment (NSTX), the newest large-scale machine in the magnetic confinement fusion (MCF) program. The development of new schemes for plasma confinement involves the interplay of experimental results and theoretical interpretations. A fundamental requirement, for example, is a determination of the equilibria for these configurations. For MCF, this is well established in the solutions of the Grad-Shafranov equation. While it is simple to state its basis in the balance between the kinetic and magnetic pressures, what they are as functions of space and time are often not easy to obtain. Quantities like the plasma pressure and current density are not directly measurable. They are derived from data that are themselves complex products of more basic parameters. The same difficulties apply to the understanding of plasma instabilities. Not only are the needs for spatial and temporal resolution more stringent, but the wave parameters which characterize the instabilities are difficult to resolve. We will show how solutions to the problems of diagnostic design on NSTX, and the physics insight the data analysis provides, benefits both NSTX and the broader scientific community.

  19. Department of Energy Review of the National Spherical Torus Experiment (NSTX) Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    -903-0269 stephen.meador@science.doe.gov Review Committee Subcommittee 1: Technical *Tom McManamy, ORNL 865@fnal.gov Subcommittee 3: Cost and Schedule *Kin Chao, DOE/SC 301-903-4116 kin.chao@science.doe.gov Tim Maier, DOE/BHSO 631-344-2402 tmaier@bnl.gov Darren Morton, DOE/OECM 202-287-1940 darren.morton@hq.doe.gov Mark

  20. National Spherical Torus Experiment (NSTX) | U.S. DOE Office of Science

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe 26thI D- 6AerosolsofMarshallMissionScience (SC)(SC)

  1. Lithium Pellet Injector Development for NSTX

    SciTech Connect (OSTI)

    G. Gettelfinger; J. Dong; R. Gernhardt; H. Kugel; P. Sichta; J. Timberlake

    2003-12-04

    A pellet injector suitable for the injection of lithium and other low-Z pellets of varying mass into plasmas at precise velocities from 5 to 500 m/s is being developed for use on NSTX (National Spherical Torus Experiment). The ability to inject low-Z impurities will significantly expand NSTX experimental capability for a broad range of diagnostic and operational applications. The architecture employs a pellet-carrying cartridge propelled through a guide tube by deuterium gas. Abrupt deceleration of the cartridge at the end of the guide tube results in the pellet continuing along its intended path, thereby giving controlled reproducible velocities for a variety of pellets materials and a reduced gas load to the torus. The planned injector assembly has four hundred guide tubes contained in a rotating magazine with eight tubes provided for injection into plasmas. A PC-based control system is being developed as well and will be described elsewhere in these Proceedings. The development path and mechanical performance of the injector will be described.

  2. Liquid Lithium Divertor and Scrape-Off-Layer Interactions on the National Spherical Torus Experiment: 2010 ? 2013 Progress Report

    SciTech Connect (OSTI)

    None

    2013-08-27

    The implementation of the liquid Lithium Divertor (LLD) in NSTX presented a unique opportunity in plasma-material interactions studies. A high density Langmuir Probe (HDLP) array utilizing a dense pack of triple Langmuir probes was built at PPPL and the electronics designed and built by UIUC. It was shown that the HDLP array could be used to characterize the modification of the EEDF during lithium experiments on NSTX as well as characterize the transient particle loads during lithium experiments as a means to study ELMs. With NSTX being upgraded and a new divertor being installed, the HDLP array will not be used in NSTX-U. However UIUC is currently helping to develop two new systems for depositing lithium into NSTX-U, a Liquid Lithium Pellet Dripper (LLPD) for use with the granular injector for ELM mitigation and control studies as well as an Upward-Facing Lithium Evaporator (U-LITER) based on a flash evaporation system using an electron beam. Currently UIUC has Daniel Andruczyk Stationed at PPPL and is developing these systems as well as being involved in preparing the Materials Analysis Particle Probe (MAPP) for use in LTX and NSTX-U. To date the MAPP preparations have been completed. New sample holders were designed by UIUC?s Research Engineer at PPPL and manufactured at PPPL and installed. MAPP is currently being used on LTX to do calibration and initial studies. The LLPD has demonstrated that it can produce pellets. There is still some adjustments needed to control the frequency and particle size. Equipment for the U-LITER has arrived and initial test are being made of the electron beam and design of the U-LITER in progress. It is expected to have these ready for the first run campaign of NSTX-U.

  3. Progress Towards High Performance, Steady-state Spherical Torus

    SciTech Connect (OSTI)

    M. Ono; M.G. Bell; R.E. Bell; T. Bigelow; M. Bitter; W. Blanchard; J. Boedo; C. Bourdelle; C. Bush; W. Choe; J. Chrzanowski; D.S. Darrow; S.J. Diem; R. Doerner; P.C. Efthimion; J.R. Ferron; R.J. Fonck; E.D. Fredrickson; G.D. Garstka; D.A. Gates; T. Gray; L.R. Grisham; W. Heidbrink; K.W. Hill; D. Hoffman; T.R. Jarboe; D.W. Johnson; R. Kaita; S.M. Kaye; C. Kessel; J.H. Kim; M.W. Kissick; S. Kubota; H.W. Kugel; B.P. LeBlanc; K. Lee; S.G. Lee; B.T. Lewicki; S. Luckhardt; R. Maingi; R. Majeski; J. Manickam; R. Maqueda; T.K. Mau; E. Mazzucato; S.S. Medley; J. Menard; D. Mueller; B.A. Nelson; C. Neumeyer; N. Nishino; C.N. Ostrander; D. Pacella; F. Paoletti; H.K. Park; W. Park; S.F. Paul; Y.-K. M. Peng; C.K. Phillips; R. Pinsker; P.H. Probert; S. Ramakrishnan; R. Raman; M. Redi; A.L. Roquemore; A. Rosenberg; P.M. Ryan; S.A. Sabbagh; M. Schaffer; R.J. Schooff; R. Seraydarian; C.H. Skinner; A.C. Sontag; V. Soukhanovskii; J. Spaleta; T. Stevenson; D. Stutman; D.W. Swain; E. Synakowski; Y. Takase; X. Tang; G. Taylor; J. Timberlake; K.L. Tritz; E.A. Unterberg; A. Von Halle; J. Wilgen; M. Williams; J.R. Wilson; X. Xu; S.J. Zweben; R. Akers; R.E. Barry; P. Beiersdorfer; J.M. Bialek; B. Blagojevic; P.T. Bonoli; M.D. Carter; W. Davis; B. Deng; L. Dudek; J. Egedal; R. Ellis; M. Finkenthal; J. Foley; E. Fredd; A. Glasser; T. Gibney; M. Gilmore; R.J. Goldston; R.E. Hatcher; R.J. Hawryluk; W. Houlberg; R. Harvey; S.C. Jardin; J.C. Hosea; H. Ji; M. Kalish; J. Lowrance; L.L. Lao; F.M. Levinton; N.C. Luhmann; R. Marsala; D. Mastravito; M.M. Menon; O. Mitarai; M. Nagata; G. Oliaro; R. Parsells; T. Peebles; B. Peneflor; D. Piglowski; G.D. Porter; A.K. Ram; M. Rensink; G. Rewoldt; P. Roney; K. Shaing; S. Shiraiwa; P. Sichta; D. Stotler; B.C. Stratton; R. Vero; W.R. Wampler; G.A. Wurden

    2003-10-02

    Research on the Spherical Torus (or Spherical Tokamak) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect-ratio devices, such as the conventional tokamak. The Spherical Tours (ST) experiments are being conducted in various U.S. research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium-size ST research facilities: Pegasus at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the U.S., an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high-performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta (B), noninductive sustainment, ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values bT of up to 35% with the near unity central betaT have been obtained. NSTX will be exploring advanced regimes where bT up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for noninductive sustainment in NSTX is the high beta-poloidal regime, where discharges with a high noninductive fraction ({approx}60% bootstrap current + neutral-beam-injected current drive) were sustained over the resistive skin time. Research on radio-frequency-based heating and current drive utilizing HHFW (High Harmonic Fast Wave) and EBW (Electron Bernstein Wave) is also pursued on NSTX, Pegasus, and CDX-U. For noninductive start-up, the Coaxial Helicity Injection (CHI), developed in HIT/HIT-II, has been adopted on NSTX to test the method up to Ip {approx} 500 kA. In parallel, start-up using radio-frequency current drive and only external poloidal field coils are being developed on NSTX. The area of power and particle handling is expected to be challenging because of the higher power density expected in the ST relative to that in conventional aspect-ratio tokamaks. Due to its promise for power and particle handling, liquid lithium is being studied in CDX-U as a potential plasma-facing surface for a fusion reactor.

  4. Fast ion absorption of the high harmonic fast wave in the National Spherical Torus Experiment a...

    E-Print Network [OSTI]

    Egedal, Jan

    above the beam injection energy is sustained by the wave. In agreement with modeling, these experimentsFast ion absorption of the high harmonic fast wave in the National Spherical Torus Experiment a Institute of Technology, Cambridge, Massachusetts 02139 #Received 23 October 2003; accepted 19 December 2003

  5. Addressing the challenges of plasma-surface interactions in NSTX-U*

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kaita, Robert [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Abrams, Tyler [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Jaworski, Michael [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Lucia, Matthew [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Nichols, Jacob H. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Skinner, Charles H. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Stotler, Daren [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Allain, Jean Paul [University of Illinois, Urbana, IL (United States); Bedoya, Felipe [University of Illinois, Urbana, IL (United States)

    2015-04-01

    The importance of conditioning plasma-facing components (PFCs) has long been recognized as a critical element in obtaining high-performance plasmas in magnetic confinement devices. Lithium coatings, for example, have been used for decades for conditioning PFCs. Since the initial studies on the Tokamak Fusion Test Reactor, experiments on devices with different aspect ratios and magnetic geometries like the National Spherical Torus Experiment (NSTX) continue to show the relationship between lithium PFCs and good confinement and stability. While such results are promising, their empirical nature do not reflect the detailed relationship between PFCs and the dynamic conditions that occur in the tokamak environment. A first step developing an understanding such complexity will be taken in the upgrade to NSTX (NSTX-U) that is nearing completion. New measurement capabilities include the Materials Analysis and Particle Probe (MAPP) for in situ surface analysis of samples exposed to tokamak plasmas. The OEDGE suite of codes, for example, will provide a new way to model the underlying mechanisms for such material migration in NSTX-U. This will lead to a better understanding of how plasma-facing surfaces evolve during a shot, and how the composition of the plasma facing surface influences the discharge performance we observe. This paper will provide an overview of these capabilities, and highlight their importance for NSTX-U plans to transition from carbon to high-Z PFCs.

  6. Addressing the challenges of plasma-surface interactions in NSTX-U*

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kaita, Robert; Abrams, Tyler; Jaworski, Michael; Lucia, Matthew; Nichols, Jacob H.; Skinner, Charles H.; Stotler, Daren; Allain, Jean Paul; Bedoya, Felipe

    2015-04-01

    The importance of conditioning plasma-facing components (PFCs) has long been recognized as a critical element in obtaining high-performance plasmas in magnetic confinement devices. Lithium coatings, for example, have been used for decades for conditioning PFCs. Since the initial studies on the Tokamak Fusion Test Reactor, experiments on devices with different aspect ratios and magnetic geometries like the National Spherical Torus Experiment (NSTX) continue to show the relationship between lithium PFCs and good confinement and stability. While such results are promising, their empirical nature do not reflect the detailed relationship between PFCs and the dynamic conditions that occur in the tokamakmore »environment. A first step developing an understanding such complexity will be taken in the upgrade to NSTX (NSTX-U) that is nearing completion. New measurement capabilities include the Materials Analysis and Particle Probe (MAPP) for in situ surface analysis of samples exposed to tokamak plasmas. The OEDGE suite of codes, for example, will provide a new way to model the underlying mechanisms for such material migration in NSTX-U. This will lead to a better understanding of how plasma-facing surfaces evolve during a shot, and how the composition of the plasma facing surface influences the discharge performance we observe. This paper will provide an overview of these capabilities, and highlight their importance for NSTX-U plans to transition from carbon to high-Z PFCs.« less

  7. Comparison of Poloidal Velocity Meassurements to Neoclassical Theory on the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Bell, R E; Kaye, S M; Kolesnikov, R A; LeBlance, B P; Rewolldt, G; Wang, W X

    2010-04-07

    Knowledge of poloidal velocity is necessary for the determination of the radial electric field, Er, which along with its gradient is linked to turbulence suppression and transport barrier formation. Recent measurements of poloidal flow on conventional tokamaks have been reported to be an order of magnitude larger than expected from neoclassical theory. In contrast, recent poloidal velocity measurements on the NSTX spherical torus [S. M. Kaye et al., Phys. Plasmas 8, 1977 (2001)] are near or below neoclassical estimates. A novel charge exchange recombination spectroscopy diagnostic is used, which features active and passive sets of up/down symmetric views to produce line-integrated poloidal velocity measurements that do not need atomic physics corrections. Local profiles are obtained with an inversion. Poloidal velocity measurements are compared with neoclassical values computed with the codes NCLASS [W. A. Houlberg et al., Phys. Plasmas 4, 3230 (1997)] and GTC-Neo [W. X. Wang, et al., Phys. Plasmas 13, 082501 (2006)], which has been updated to handle impurities. __________________________________________________

  8. Electron Bernstein Wave Research on CDX-U and NSTX

    SciTech Connect (OSTI)

    Taylor, G.; Efthimion, P.C.; Jones, B.; Hosea, J.C.; Kaita, R.; LeBlanc, B.P.; Majeski, R.; Munsat, T.; Phillips, C.K.; Spaleta, J.; Wilson, J.R.; Rasmussen, D.; Bell, G.; Bigelow, T.S.; Carter, M.D.; Swain, D.W.; Wilgen, J.B.; Ram, A.K.; Bers, A.; Harvey, R.W.; and Forest, C.B.

    2001-05-18

    Mode-converted electron Bernstein waves (EBWs) potentially allow the measurement of local electron temperature (Te) and the implementation of local heating and current drive in spherical torus (ST) devices, which are not directly accessible to low harmonic electron cyclotron waves. This paper reports on the measurement of X-mode radiation mode-converted from EBWs observed normal to the magnetic field on the midplane of the Current Drive Experiment-Upgrade (CDX-U) and the National Spherical Torus Experiment (NSTX) spherical torus plasmas. The radiation temperature of the EBW emission was compared to Te measured by Thomson scattering and Langmuir probes. EBW mode-conversion efficiencies of over 20% were measured on both CDX-U and NSTX. Sudden increases of mode-conversion efficiency, of over a factor of three, were observed at high-confinement-mode transitions on NSTX, when the measured edge density profile steepened. The EBW mode-conversion efficiency was found to depend on the density gradient at the mode-conversion layer in the plasma scrape-off, consistent with theoretical predictions. The EBW emission source was determined by a perturbation technique to be localized at the electron cyclotron resonance layer and was successfully used for radial transport studies. Recently, a new in-vessel antenna and Langmuir probe array were installed on CDX-U to better characterize and enhance the EBW mode-conversion process. The probe incorporates a local adjustable limiter to control and maximize the mode-conversion efficiency in front of the antenna by modifying the density profile in the plasma scrape-off where fundamental EBW mode conversion occurs. Initial results show that the mode-conversion efficiency can be increased to {approximately}100% when the local limiter is inserted near the mode-conversion layer. Plans for future EBW research, including EBW heating and current-drive studies, are discussed.

  9. Dependence of Recycling and Edge Profiles on Lithium Evaporation in High Triangularity, High Performance NSTX H-mode Discharges

    SciTech Connect (OSTI)

    Maingi, R; Osborne, T H; Bell, M G; Bell, R E; Boyle, D P; Canik, J M; Dialla, A; Kaita, R; Kaye, S M; Kugel, H W; LeBlanc, B P; Sabbagh, S A; Skinner, C H; Soukhanovskii, V A

    2014-04-01

    In this paper, the effects of a pre-discharge lithium evaporation scan on highly shaped discharges in the National Spherical Torus Experiment (NSTX) are documented. Lithium wall conditioning ('dose') was routinely applied onto graphite plasma facing components between discharges in NSTX, partly to reduce recycling. Reduced D[sub]? emission from the lower and upper divertor and center stack was observed, as well as reduced midplane neutral pressure; the magnitude of reduction increased with the pre-discharge lithium dose. Improved energy confinement, both raw ?[sub]E and H-factor normalized to scalings, with increasing lithium dose was also observed. At the highest doses, we also observed elimination of edge-localized modes. The midplane edge plasma profiles were dramatically altered, comparable to lithium dose scans at lower shaping, where the strike point was farther from the lithium deposition centroid. This indicates that the benefits of lithium conditioning should apply to the highly shaped plasmas planned in NSTX-U.

  10. The Role of Lithium Conditioning in Achieving High Performance, Long Pulse H-mode Discharges in the NSTX and EAST Devices

    SciTech Connect (OSTI)

    Maingi, Rajesh; Mansfield, D. K.; Gong, X. Z.; Sun, Z.; Bell, M. G.

    2014-10-01

    In this paper, the role of lithium wall conditioning on the achievement of high performance, long pulse discharges in the National Spherical Torus Experiment (NSTX) and the Experimental Advanced Superconducting Tokamak (EAST) is documented. Common observations include recycling reduction and elimination of ELMs. In NSTX, lithium conditioning typically resulted in ELM-free operation with impurity accumulation, which was ameliorated e.g. with pulsed 3D fields to trigger controlled ELMs. Active lithium conditioning in EAST discharges has overcome this problem, producing an ELM-free Hmode with controlled density and impurities.

  11. Aspect ratio effects on neoclassical tearing modes from comparison between DIII-D and National Spherical Torus Experiment

    SciTech Connect (OSTI)

    La Haye, R. J.; Buttery, R. J. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Gerhardt, S. P. [Princeton Plasma Physics Laboratory, P.O. Box 451 Princeton, New Jersey 08543 (United States); Sabbagh, S. A. [Columbia University, 2960 Broadway, New York, New York 10027-6900 (United States); Brennan, D. P. [University of Tulsa, 800 South Tucker Drive, Tulsa, Oklahoma 74104 (United States)

    2012-06-15

    Neoclassical tearing mode islands are sustained by helically perturbed bootstrap currents arising at finite beta from toroidal effects that trap a fraction of the particles in non-circulating orbits. DIII-D and NSTX are here operated with similar shape and cross-sectional area but almost a factor of two difference in inverse aspect ratio a/R. In these experiments, destabilized n=1 tearing modes were self-stabilized (reached the 'marginal point') by reducing neutral-beam power and thus beta. The measure of the marginal island gives information on the small-island stabilizing physics that in part (with seeding) governs onset. The marginal island width on NSTX is found to be about three times the ion banana width and agrees with that measured in DIII-D, except for DIII-D modes closer to the magnetic axis, which are about two times the ion banana width. There is a balance of the helically perturbed bootstrap term with small island effects with the sum of the classical and curvature terms in the modified Rutherford equation for tearing-mode stability at the experimental marginal point. Empirical evaluation of this sum indicates that while the stabilizing effect of the curvature term is negligible in DIII-D, it is important in NSTX. The mode temporal behavior from the start of neutral-beam injection reduction also suggests that NSTX operates closer to marginal classical tearing stability; this explains why there is little hysteresis in beta between mode onset, saturation, and self-stabilization (while DIII-D has large hysteresis in beta). NIMROD code module component calculations based on DIII-D and NSTX reconstructed experimental equilibria are used to diagnose and confirm the relative importance of the stabilizing curvature effect, an advantage for low aspect ratio; the relatively greater curvature effect makes for less susceptibility to NTM onset even if the classical tearing stability index is near marginal.

  12. Status and Plans for the National Spherical Torus Experimental Research Facility

    SciTech Connect (OSTI)

    M. Ono; M.G. Bell; R.E. Bell; J.M. Bialek; T. Bigelow; M. Bitter; plus 148 additional authors

    2005-07-27

    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. In support of the NSTX research goal, research tools are being developed by the NSTX team. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a high beta Demo device based on the ST, are being considered. For these, it is essential to develop high performance (high beta and high confinement), steady-state (non-inductively driven) ST operational scenarios and an efficient solenoid-free start-up concept. We will also briefly describe the Next-Step-ST (NSST) device being designed to address these issues in fusion-relevant plasma conditions.

  13. NSTX: Facility/Research Highlights and Near Term Facility Plans

    SciTech Connect (OSTI)

    M. Ono

    2008-11-19

    The National Spherical Torus Experiment (NSTX) is a collaborative mega-ampere-class spherical torus research facility with high power heating and current drive systems and the state-of-the-art comprehensive diagnostics. For the 2008 experimental campaign, the high harmonic fast wave (HHFW) heating efficiency in deuterium improved significantly with lithium evaporation and produced a record central Te of 5 keV. The HHFW heating of NBI-heated discharges was also demonstrated for the first time with lithium application. The EBW emission in H-mode was also improved dramatically with lithium which was shown to be attributable to reduced edge collisional absorption. Newly installed FIDA energetic particle diagnostic measured significant transport of energetic ions associated with TAE avalanche as well as n=1 kink activities. A full 75 channel poloidal CHERS system is now operational yielding tantalizing initial results. In the near term, major upgrade activities include a liquid-lithium divertor target to achieve lower collisionality regime, the HHFW antenna upgrades to double its power handling capability in H-mode, and a beam-emission spectroscopy diagnostic to extend the localized turbulence measurements toward the ion gyro-radius scale from the present concentration on the electron gyro-radius scale. For the longer term, a new center stack to significantly expand the plasma operating parameters is planned along with a second NBI system to double the NBI heating and CD power and provide current profile control. These upgrades will enable NSTX to explore fully non-inductive operations over a much expanded plasma parameter space in terms of higher plasma temperature and lower collisionality, thereby significantly reducing the physics parameter gap between the present NSTX and the projected next-step ST experiments.

  14. Local scrape-off layer control using biased electrodes in NSTX

    SciTech Connect (OSTI)

    Zweben, S. J.; Maqueda, R. J.; Roquemore, A. L.; Bush, C. E.; Kaita, R.; Marsala, R. J.; Raitses, Y.; Cohen, R. H.; Ryutov, D. D.

    2009-04-24

    An experiment was designed to test the theory that biased electrodes can affect the local scrape-off layer (SOL) width by creating a strong radial ExB drift [Cohen, R.H. and Ryutov, D.D, Nucl. Fusion 37, 621 (1997)]. These electrodes were located near the outer midplane in the SOL of the National Spherical Torus Experiment (NSTX). The electrodes were biased at up to ?100 Volts, and the radial profile of the plasma between them was measured by an array of Langmuir probes. The biasing caused large changes in the local SOL profiles at least qualitatively consistent with this theory.

  15. Two-dimensional AXUV-based radiated power density diagnostics on NSTX-U

    SciTech Connect (OSTI)

    Faust, I.; Parker, R. R. [MIT - Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Delgado-Aparicio, L.; Bell, R. E.; Diallo, A.; Gerhardt, S. P.; LeBlanc, B.; Kozub, T. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Tritz, K. [The Johns Hopkins University, Baltimore, Maryland 21209 (United States); Stratton, B. C. [MIT - Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States)

    2014-11-15

    A new set of radiated-power-density diagnostics for the National Spherical Torus Experiment Upgrade (NSTX-U) tokamak have been designed to measure the two-dimensional poloidal structure of the total photon emissivity profile in order to perform power balance, impurity transport, and magnetohydrodynamic studies. Multiple AXUV-diode based pinhole cameras will be installed in the same toroidal angle at various poloidal locations. The local emissivity will be obtained from several types of tomographic reconstructions. The layout and response expected for the new radially viewing poloidal arrays will be shown for different impurity concentrations to characterize the diagnostic sensitivity. The radiated power profile inverted from the array data will also be used for estimates of power losses during transitions from various divertor configurations in NSTX-U. The effect of in-out and top/bottom asymmetries in the core radiation from high-Z impurities will be addressed.

  16. Development of a compact tomography camera system using a multianode photomultiplier tube for compact torus experiments

    SciTech Connect (OSTI)

    Tomuro, H.; Asai, T.; Iguchi, K.; Takahashi, Ts.; Hirano, Y. [Department of Physics, College of Science and Technology, Nihon University, Tokyo 101-8308 (Japan)

    2010-10-15

    A compact tomography camera system consisting of a photomultiplier tube, a multislit optical system, and a band-pass interference filter has been developed. The viewing area and spatial resolution can be configured by the arrangement of the slit system. The camera system has been specially designed for self-organized compact torus experiments having strong magnetohydrodynamics events with a submicrosecond time-scale. The developed system has been tested on a field-reversed configuration formed by the field-reversed theta-pinch. Performance evaluation of the system has been performed by comparison to the former optical system.

  17. Flow and shear behavior in the edge and scrape-off layer of L-mode plasmas in National Spherical Torus Experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sechrest, Y.; Munsat, T.; D’Ippolito, D. A.; Maqueda, R. J.; Myra, J. R.; Russell, D.; Zweben, S. J.

    2011-01-01

    Fluctuations in the edge and scrape-off layer (SOL) of L-mode plasmas in the National Spherical Torus Experiment (NSTX) as observed by the gas puff imaging (GPI) diagnostic are studied. Calculation of local, time resolved velocity maps using the Hybrid Optical Flow and Pattern Matching Velocimetry (HOP-V) code enables analysis of turbulent flow and shear behavior. Periodic reversals in the direction of the poloidal flow near the separatrix are observed. Also, poloidal velocities and their radial shearing rate are found to be well correlated with the fraction of D? light contained in the SOL, which acts as a measure of turbulentmore »bursts. The spectra of GPI intensity and poloidal velocity both have a strong feature near 3 kHz, which appears to correspond with turbulent bursts. This mode exhibits a poloidal structure with poloidal wavenumber of 7.7 m-1 for GPI intensity and 3.4 m-1 for poloidal velocity, and the poloidal velocity fluctuations near 3 kHz remain coherent over length scales in excess of the turbulent scales. Furthermore, recent SOL Turbulence (SOLT) simulations find a parameter regime that exhibits periodic bursty transport and shares many qualitative similarities with the experimental data. Strong correlations between the shearing rate and the turbulent bursts are observed for time periods of ~ 2 ms, but the relationship is complicated by several factors. Finally, measurements of the radial profiles of the Reynolds shear stresses are reported. These radial profiles exhibit many similarities for several shots, and a region with positive radial gradient is seen to be coincident with local flow shear.« less

  18. Flow and shear behavior in the edge and scrape-off layer of L-mode plasmas in National Spherical Torus Experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sechrest, Y. [Univ. of Colorado, Boulder, CO (United States); Munsat, T. [Univ. of Colorado, Boulder, CO (United States); D’Ippolito, D. A. [Lodestar Research Corp., Boulder, CO (United States); Maqueda, R. J. [Princeton Plasma Physics Lab., NJ (United States); Myra, J. R. [Lodestar Research Corp., Boulder, CO (United States); Russell, D. [Lodestar Research Corp., Boulder, CO (United States); Zweben, S. J. [Princeton Plasma Physics Lab., NJ (United States)

    2011-01-10

    Fluctuations in the edge and scrape-off layer (SOL) of L-mode plasmas in the National Spherical Torus Experiment (NSTX) [S. M. Kaye et al.,Phys. Plasmas 8, 1977 (2001)] as observed by the gas puff imaging (GPI) diagnostic are studied. Calculation of local, time resolved velocity maps using the Hybrid Optical Flow and Pattern Matching Velocimetry (HOP-V) code enables analysis of turbulent flow and shear behavior. Periodic reversals in the direction of the poloidal flow near the separatrix are observed. Also, poloidal velocities and their radial shearing rate are found to be well correlated with the fraction of D? light contained in the SOL, which acts as a measure of turbulent bursts. The spectra of GPI intensity and poloidal velocity both have a strong feature near 3 kHz, which appears to correspond with turbulent bursts. This mode exhibits a poloidal structure with poloidal wavenumber of 7.7 m-1 for GPI intensity and 3.4 m-1 for poloidal velocity, and the poloidal velocity fluctuations near 3 kHz remain coherent over length scales in excess of the turbulent scales. Furthermore, recent SOL Turbulence (SOLT) simulations find a parameter regime that exhibits periodic bursty transport and shares many qualitative similarities with the experimental data. Strong correlations between the shearing rate and the turbulent bursts are observed for time periods of ~ 2 ms, but the relationship is complicated by several factors. Finally, measurements of the radial profiles of the Reynolds shear stresses are reported. These radial profiles exhibit many similarities for several shots, and a region with positive radial gradient is seen to be coincident with local flow shear.

  19. Advanced ST Plasma Scenario Simulations for NSTX

    SciTech Connect (OSTI)

    C.E. Kessel; E.J. Synakowski; D.A. Gates; R.W. Harvey; S.M. Kaye; T.K. Mau; J. Menard; C.K. Phillips; G. Taylor; R. Wilson; the NSTX Research Team

    2004-10-28

    Integrated scenario simulations are done for NSTX [National Spherical Torus Experiment] that address four primary milestones for developing advanced ST configurations: high {beta} and high {beta}{sub N} inductive discharges to study all aspects of ST physics in the high-beta regime; non-inductively sustained discharges for flattop times greater than the skin time to study the various current-drive techniques; non-inductively sustained discharges at high {beta} for flattop times much greater than a skin time which provides the integrated advanced ST target for NSTX; and non-solenoidal start-up and plasma current ramp-up. The simulations done here use the Tokamak Simulation Code (TSC) and are based on a discharge 109070. TRANSP analysis of the discharge provided the thermal diffusivities for electrons and ions, the neutral-beam (NB) deposition profile, and other characteristics. CURRAY is used to calculate the High Harmonic Fast Wave (HHFW) heating depositions and current drive. GENRAY/CQL3D is used to establish the heating and CD [current drive] deposition profiles for electron Bernstein waves (EBW). Analysis of the ideal-MHD stability is done with JSOLVER, BALMSC, and PEST2. The simulations indicate that the integrated advanced ST plasma is reachable, obtaining stable plasmas with {beta} {approx} 40% at {beta}{sub N}'s of 7.7-9, I{sub P} = 1.0 MA, and B{sub T} = 0.35 T. The plasma is 100% non-inductive and has a flattop of 4 skin times. The resulting global energy confinement corresponds to a multiplier of H{sub 98(y,2)} = 1.5. The simulations have demonstrated the importance of HHFW heating and CD, EBW off-axis CD, strong plasma shaping, density control, and early heating/H-mode transition for producing and optimizing these plasma configurations.

  20. Analysis of NSTX Upgrade OH Magnet and Center Stack

    SciTech Connect (OSTI)

    A. Zolfaghari, P. Titus, J. Chrzanowski, A. Salehzadeh, F. Dahlgren

    2010-11-30

    The new ohmic heating (OH) coil and center stack for the National Spherical Torus Experiment (NSTX) upgrade are required to meet cooling and structural requirements for operation at the enhanced 1 Tesla toroidal field and 2 MA plasma current. The OH coil is designed to be cooled in the time between discharges by water flowing in the center of the coil conductor. We performed resistive heating and thermal hydraulic analyses to optimize coolant channel size to keep the coil temperature below 100 C and meet the required 20 minute cooling time. Coupled electromagnetic, thermal and structural FEA analyses were performed to determine if the OH coil meets the requirements of the structural design criteria. Structural response of the OH coil to its self-field and the field from other coils was analyzed. A model was developed to analyze the thermal and electromagnetic interaction of centerstack components such as the OH coil, TF inner legs and the Bellville washer preload mechanism. Torsional loads from the TF interaction with the OH and poloidal fields are transferred through the TF flag extensions via a torque transfer coupling to the rest of the tokamak structure. A 3D FEA analysis was performed to qualify this design. The results of these analyses, which will be presented in this paper, have led to the design of OH coil and centerstack components that meet the requirements of the NSTX-upgrade structural design criteria.

  1. Recent Progress on Spherical Torus Research

    SciTech Connect (OSTI)

    Ono, Masayuki; Kaita, Robert

    2014-01-01

    The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its aspect ratio (A = R0/a) reduced to A ~ 1.5, well below the normal tokamak operating range of A ? 2.5. As the aspect ratio is reduced, the ideal tokamak beta ? (radio of plasma to magnetic pressure) stability limit increases rapidly, approximately as ? ~ 1/A. The plasma current it can sustain for a given edge safety factor q-95 also increases rapidly. Because of the above, as well as the natural elongation ?, which makes its plasma shape appear spherical, the ST configuration can yield exceptionally high tokamak performance in a compact geometry. Due to its compactness and high performance, the ST configuration has various near term applications, including a compact fusion neutron source with low tritium consumption, in addition to its longer term goal of attractive fusion energy power source. Since the start of the two megaampere class ST facilities in 2000, National Spherical Torus Experiment (NSTX) in the US and Mega Ampere Spherical Tokamak (MAST) in UK, active ST research has been conducted worldwide. More than sixteen ST research facilities operating during this period have achieved remarkable advances in all of fusion science areas, involving fundamental fusion energy science as well as innovation. These results suggest exciting future prospects for ST research both near term and longer term. The present paper reviews the scientific progress made by the worldwide ST research community during this new mega-ampere-ST era.

  2. Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gerhardt, S. P.; Fredrickson, E.; Guttadora, L.; Kaita, R.; Kugel, H.; Menard, J.; Takahashi, H.

    2011-10-06

    This paper describes techniques for measuring halo currents, and their associated toroidal peaking, in the National Spherical Torus Experiments. The measurements are based on three techniques: (i) measurement of the toroidal field created by the poloidal halo current, either with segmented Rogowski coils or discrete toroidal field sensors, (ii) the direct measurement of halo currents into specially instrument tiles, and (iii) small Rogowski coils placed on the mechanical supports of in-vessel components. For the segmented Rogowski coils and discrete toroidal field detectors, it is shown that the toroidal peaking factor inferred from the data is significantly less than the peakingmore »factor of the underlying halo current distribution, and a simple model is developed to relate the two. For the array of discrete toroidal field detectors and small Rogowski sensors, the compensation steps that are used to isolate the halo current signal are described. The electrical and mechanical design of compact under-tile resistive shunts and mini-Rogowski coils is described. Example data from the various systems is shown.« less

  3. Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Gerhardt, S. P.; Fredrickson, E.; Guttadora, L.; Kaita, R.; Kugel, H.; Menard, J. [Princeton Plasma Physics Laboratory, Plainsboro, New Jersey 08540 (United States); Takahashi, H. [Princeton Fusion Research LLC, Princeton, New Jersey 08540 (United States)

    2011-10-15

    This paper describes techniques for measuring halo currents, and their associated toroidal peaking, in the National Spherical Torus Experiments [M. Ono et al., Nucl. Fusion 40, 557 (2000)]. The measurements are based on three techniques: (1) measurement of the toroidal field created by the poloidal halo current, either with segmented Rogowski coils or discrete toroidal field sensors, (2) the direct measurement of halo currents into specially instrument tiles, and (3) small Rogowski coils placed on the mechanical supports of in-vessel components. For the segmented Rogowski coils and discrete toroidal field detectors, it is shown that the toroidal peaking factor inferred from the data is significantly less than the peaking factor of the underlying halo current distribution, and a simple model is developed to relate the two. For the array of discrete toroidal field detectors and small Rogowski sensors, the compensation steps that are used to isolate the halo current signal are described. The electrical and mechanical design of compact under-tile resistive shunts and mini-Rogowski coils is described. Example data from the various systems are shown.

  4. Snowflake divertor configuration studies for NSTX-Upgrade

    SciTech Connect (OSTI)

    Soukhanovskii, V A

    2011-11-12

    Snowflake divertor experiments in NSTX provide basis for PMI development toward NSTX-Upgrade. Snowflake configuration formation was followed by radiative detachment. Significant reduction of steady-state divertor heat flux observed in snowflake divertor. Impulsive heat loads due to Type I ELMs are partially mitigated in snowflake divertor. Magnetic control of snowflake divertor configuration is being developed. Plasma material interface development is critical for NSTX-U success. Four divertor coils should enable flexibility in boundary shaping and control in NSTX-U. Snowflake divertor experiments in NSTX provide good basis for PMI development in NSTX-Upgrade. FY 2009-2010 snowflake divertor experiments in NSTX: (1) Helped understand control of magnetic properties; (2) Core H-mode confinement unchanged; (3) Core and edge carbon concentration reduced; and (4) Divertor heat flux significantly reduced - (a) Steady-state reduction due to geometry and radiative detachment, (b) Encouraging results for transient heat flux handling, (c) Combined with impurity-seeded radiative divertor. Outlook for snowflake divertor in NSTX-Upgrade: (1) 2D fluid modeling of snowflake divertor properties scaling - (a) Edge and divertor transport, radiation, detachment threshold, (b) Compatibility with cryo-pump and lithium conditioning; (2) Magnetic control development; and (3) PFC development - PFC alignment and PFC material choice.

  5. A dual wavelength imaging system for plasma-surface interaction studies on the National Spherical Torus Experiment Upgrade

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    A dual wavelength imaging system for plasma-surface interaction studies on the National Spherical.), quantitative analysis of emission from impurity or fuel atoms (e.g., in DIII- D10 , NSTX11 , etc.), real

  6. November 10, 1998 Physics Design of the National Spherical Torus

    E-Print Network [OSTI]

    NSTX is to prove the principles of spherical torus physics by producing high- t plasmas that are non an attractive path to a reactor or VolumetricNeutron Source VNS.The ST fusion core would be small under construction. Various reactor concepts have been advanced for the ST,7,8 and these have identi ed

  7. Biasing, Acquisition and Interpretation of a Dense Langmuir Probe Array in NSTX

    SciTech Connect (OSTI)

    Jaworski, M. A.; Kallman, J.; Kaita, R.; Kugel, H.; LeBlanc, B.; Marsala, R.; Ruzic, D.

    2010-09-22

    A dense array of 99 Langmuir probes has been installed in the lower divertor region of the National Spherical Torus Experiments (NSTX). This array is instrumented with a system of elec- tronics that allows flexibility in the choice of probes to bias as well as the type of measurement (including standard swept, single probe, triple probe and operation as passive floating potential and scrape-off-layer (SOL) current monitors). The use of flush-mounted probes requires careful inter- pretation. The time dependent nature of the SOL makes swept-probe traces difficult to interpret. To overcome these challenges, the single- and triple-Langmuir probe signals are used in comple- mentary fashion to determine the temperature and density at the probe location. A comparison to mid-plane measurements is made. Work is supported by DOE contracts DE-AC02-09CHI1466 and DE-PS02-07ER07-29.

  8. NSTX-U Advances in Real-time C++11 on Linux

    SciTech Connect (OSTI)

    Erickson, Keith G

    2014-04-01

    Programming languages like C and Ada combined with proprietary embedded operating systems have dominated the real-time application space for decades. The new C++11standard includes native, language-level support for concurrency, a required feature for any nontrivial event-oriented real-time software. Threads, Locks, and Atomics now exist to provide the necessary tools to build the structures that make up the foundation of a complex real-time system. The National Spherical Torus Experiment Upgrade (NSTX-U) at the Princeton Plasma Physics Laboratory (PPPL) is breaking new ground with the language as applied to the needs of fusion devices. A new Digital Coil Protection System (DCPS) will serve as the main protection mechanism for the magnetic coils, and it is written entirely in C++11 running on Concurrent Computer Corporation's real-time operating system, RedHawk Linux. It runs over 600 algorithms in a 5 kHz control loop that determine whether or not to shut down operations before physical damage occurs. To accomplish this, NSTX-U engineers developed software tools that do not currently exist elsewhere, including real-time atomic synchronization, real-time containers, and a real-time logging framework. Together with a recent (and carefully configured) version of the GCC compiler, these tools enable data acquisition, processing, and output using a conventional operating system to meet a hard real-time deadline (that is, missing one periodic is a failure) of 200 microseconds.

  9. NSTX-U Advances in Real-Time C++11 on Linux

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Erickson, Keith G.

    2015-08-14

    Programming languages like C and Ada combined with proprietary embedded operating systems have dominated the real-time application space for decades. The new C++11standard includes native, language-level support for concurrency, a required feature for any nontrivial event-oriented real-time software. Threads, Locks, and Atomics now exist to provide the necessary tools to build the structures that make up the foundation of a complex real-time system. The National Spherical Torus Experiment Upgrade (NSTX-U) at the Princeton Plasma Physics Laboratory (PPPL) is breaking new ground with the language as applied to the needs of fusion devices. A new Digital Coil Protection System (DCPS) willmore »serve as the main protection mechanism for the magnetic coils, and it is written entirely in C++11 running on Concurrent Computer Corporation's real-time operating system, RedHawk Linux. It runs over 600 algorithms in a 5 kHz control loop that determine whether or not to shut down operations before physical damage occurs. To accomplish this, NSTX-U engineers developed software tools that do not currently exist elsewhere, including real-time atomic synchronization, real-time containers, and a real-time logging framework. Together with a recent (and carefully configured) version of the GCC compiler, these tools enable data acquisition, processing, and output using a conventional operating system to meet a hard real-time deadline (that is, missing one periodic is a failure) of 200 microseconds.« less

  10. NSTX-U Control System Upgrades

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Erickson, K. G.; Gates, D. A.; Gerhardt, S. P.; Lawson, J. E.; Mozulay, R.; Sichta, P.; Tchilinguirian, G. J.

    2014-06-01

    The National Spherical Tokamak Experiment (NSTX) is undergoing a wealth of upgrades (NSTX-U). These upgrades, especially including an elongated pulse length, require broad changes to the control system that has served NSTX well. A new fiber serial Front Panel Data Port input and output (I/O) stream will supersede the aging copper parallel version. Driver support for the new I/O and cyber security concerns require updating the operating system from Redhat Enterprise Linux (RHEL) v4 to RedHawk (based on RHEL) v6. While the basic control system continues to use the General Atomics Plasma Control System (GA PCS), the effort to forward port the entire software package to run under 64-bit Linux instead of 32-bit Linux included PCS modifications subsequently shared with GA and other PCS users. Software updates focused on three key areas: (1) code modernization through coding standards (C99/C11), (2) code portability and maintainability through use of the GA PCS code generator, and (3) support of 64-bit platforms. Central to the control system upgrade is the use of a complete real time (RT) Linux platform provided by Concurrent Computer Corporation, consisting of a computer (iHawk), an operating system and drivers (RedHawk), and RT tools (NightStar). Strong vendor support coupled with an extensive RT toolset influenced this decision. The new real-time Linux platform, I/O, and software engineering will foster enhanced capability and performance for NSTX-U plasma control.

  11. Migration of NSTX MDSPlus

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . Zimmer minor revs noted 07OCT2008 (ps) #12;Agenda · Introduction · MDSplus System Software · Application the opportunity to build our MDSplus environment from `bare metal'. ­ Promotes the development of documentation MDSplus system software and tailor it to the PPPL/NSTX environment. · Port CAMAC IDL applications

  12. Novel Use of Water Soluble "Aquapour" As A Temporary Spacer During Coil Winding For The NSTX-U Centerstack

    SciTech Connect (OSTI)

    Mardenfeld, Michael

    2013-07-01

    A major facility upgrade to the National Spherical Torus eXperiment (NSTX-U) is currently underway at Princeton Plasma Physics Laboratory (PPPL). A key component of NSTX-U is the fabrication of a new, higher field centerstack (CS). In order to simultaneously provide robust joints between the inner and outer legs of the Toroidal Field Coils (TF) and minimize radial build, the NSTX-U CS design requires that the Ohmic Heating solenoid (OH) be wound directly on the inner TF bundle. To protect the OH against thermal expansion stress during scenarios where the inner TF bundle is hot but the OH is relatively cool, the completed CS will have a 0.100 inch annular gap between the outer diameter of the TF bundle and the inner diameter of the OH solenoid. "Aquapour", a proprietary material produced by the Advanced Ceramics Manufacturing Company will be used during manufacture to produce this gap. After the TF bundle is vacuum pressure impregnated and cured, a cylindrical "clam shell" mold will be assembled around it, and a slurry of powdered Aquapour and water will be pumped into the annular space between the mold and TF bundle. Subsequent baking will turn the Aquapour solid, and a protective layer of wet lay-up fiberglass and resin will be added. The OH solenoid will be wound directly on this wet lay-up shell. After vacuum pressure impregnation of the OH, the water soluble Aquapour will be washed away, leaving the required radial clearance between the TF and OH. This paper will describe prototyping and testing of this process, and plans for use on the actual CS fabrication.

  13. NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 FAILURE MODES AND EFFECTS ANALYSIS

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 10 Dated: November 2014 Prepared By: Name/WBS Signature Name: ________________________________________________ Ron Strykowsky, NSTX Upgrade Project Manager #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71

  14. Final Scientific/Technical Report, USDOE Award DE-FG-02ER54684, Recipient: CompX, Project Title: Fokker-Planck/Ray Tracing for Electron Bernstein and Fast Wave Modeling in Support of NSTX.

    SciTech Connect (OSTI)

    R.W. Harvey, CompX, Del Mar, CA 92014

    2009-11-12

    This DOE grant supported fusion energy research, a potential long-term solution to the world's energy needs. Magnetic fusion, exemplified by confinement of very hot ionized gases, i.e., plasmas, in donut-shaped tokamak vessels is a leading approach for this energy source. Thus far, a mixture of hydrogen isotopes has produced 10's of megawatts of fusion power for seconds in a tokamak reactor at Princeton Plasma Physics Laboratory in New Jersey. The research grant under consideration, ER54684, uses computer models to aid in understanding and projecting efficacy of heating and current drive sources in the National Spherical Torus Experiment, a tokamak variant, at PPPL. The NSTX experiment explores the physics of very tight aspect ratio, almost spherical tokamaks, aiming at producing steady-state fusion plasmas. The current drive is an integral part of the steady-state concept, maintaining the magnetic geometry in the steady-state tokamak. CompX further developed and applied models for radiofrequency (rf) heating and current drive for applications to NSTX. These models build on a 30 year development of rf ray tracing (the all-frequencies GENRAY code) and higher dimensional Fokker-Planck rf-collisional modeling (the 3D collisional-quasilinear CQL3D code) at CompX. Two mainline current-drive rf modes are proposed for injection into NSTX: (1) electron Bernstein wave (EBW), and (2) high harmonic fast wave (HHFW) modes. Both these current drive systems provide a means for the rf to access the especially high density plasma--termed high beta plasma--compared to the strength of the required magnetic fields. The CompX studies entailed detailed modeling of the EBW to calculate the efficiency of the current drive system, and to determine its range of flexibility for driving current at spatial locations in the plasma cross-section. The ray tracing showed penetration into NSTX bulk plasma, relatively efficient current drive, but a limited ability to produce current over the whole radial plasma cross-section. The actual EBW experiment will cost several million dollars, and remains in the proposal stage. The HHFW current drive system has been experimentally implemented on NSTX, and successfully drives substantial current. The understanding of the experiment is to be accomplished in terms of general concepts of rf current drive, and also detailed modeling of the experiment which can discern the various competing processes which necessarily occur simultaneously in the experiment. An early discovery of the CompX codes, GENRAY and CQL3D, was that there could be significant interference between the neutral beam injection fast ions in the machine (injected for plasma heating) and the HHFW energy. Under many NSTX experimental conditions, power which could go to the fast ions would then be unavailable for current drive by the desired HHFW interaction with electrons. This result has been born out by experiments; the modeling helps in understanding difficulties with HHFW current drive, and has enabled adjustment of the experiment to avoid interaction with neutral beam injected fast ions thereby achieving stronger HHFW current drive. The detailed physics modeling of the various competing processes is almost always required in fusion energy plasma physics, to ensure a reasonably accurate and certain interpretation of the experiment, enabling the confident design of future, more advanced experiments and ultimately a commercial fusion reactor. More recent work entails detailed investigation of the interaction of the HHFW radiation for fast ions, accounting for the particularly large radius orbits in NSTX, and correlations between multiple HHFW-ion interactions. The spherical aspect of the NSTX experiment emphasized particular physics such as the large orbits which are present to some degree in all tokamaks, but gives clearer clues on the resulting physics phenomena since competing physics effects are reduced.

  15. NSTX-U Control System Upgrades

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Erickson, K. G.; Gates, D. A.; Gerhardt, S. P.; Lawson, J. E.; Mozulay, R.; Sichta, P.; Tchilinguirian, G. J.

    2014-06-01

    The National Spherical Tokamak Experiment (NSTX) is undergoing a wealth of upgrades (NSTX-U). These upgrades, especially including an elongated pulse length, require broad changes to the control system that has served NSTX well. A new fiber serial Front Panel Data Port input and output (I/O) stream will supersede the aging copper parallel version. Driver support for the new I/O and cyber security concerns require updating the operating system from Redhat Enterprise Linux (RHEL) v4 to RedHawk (based on RHEL) v6. While the basic control system continues to use the General Atomics Plasma Control System (GA PCS), the effort to forwardmore »port the entire software package to run under 64-bit Linux instead of 32-bit Linux included PCS modifications subsequently shared with GA and other PCS users. Software updates focused on three key areas: (1) code modernization through coding standards (C99/C11), (2) code portability and maintainability through use of the GA PCS code generator, and (3) support of 64-bit platforms. Central to the control system upgrade is the use of a complete real time (RT) Linux platform provided by Concurrent Computer Corporation, consisting of a computer (iHawk), an operating system and drivers (RedHawk), and RT tools (NightStar). Strong vendor support coupled with an extensive RT toolset influenced this decision. The new real-time Linux platform, I/O, and software engineering will foster enhanced capability and performance for NSTX-U plasma control.« less

  16. Edge transport studies in the edge and scrape-off layer of the National Spherical Torus Experiment with Langmuir probes

    SciTech Connect (OSTI)

    Boedo, J. A. Rudakov, D. L.; Myra, J. R.; D'Ippolito, D. A.; Zweben, S.; Maingi, R.; Maqueda, R. J.; Bell, R.; Kugel, H.; Leblanc, B.; Roquemore, L. A.; Soukhanovskii, V. A.; Ahn, J. W.; Canik, J.; Crocker, N.

    2014-04-15

    Transport and turbulence profiles were directly evaluated using probes for the first time in the edge and scrape-off layer (SOL) of NSTX [Ono et al., Nucl. Fusion 40, 557 (2000)] in low (L) and high (H) confinement, low power (P{sub in}? 1.3?MW), beam-heated, lower single-null discharges. Radial turbulent particle fluxes peak near the last closed flux surface (LCFS) at ?4×10{sup 21}?s{sup ?1} in L-mode and are suppressed to ?0.2×10{sup 21}?s{sup ?1} in H mode (80%–90% lower) mostly due to a reduction in density fluctuation amplitude and of the phase between density and radial velocity fluctuations. The radial particle fluxes are consistent with particle inventory based on SOLPS fluid modeling. A strong intermittent component is identified. Hot, dense plasma filaments 4–10?cm in diameter, appear first ?2?cm inside the LCFS at a rate of ?1×10{sup 21}?s{sup ?1} and leave that region with radial speeds of ?3–5?km/s, decaying as they travel through the SOL, while voids travel inward toward the core. Profiles of normalized fluctuations feature levels of 10% inside LCFS to ?150% at the LCFS and SOL. Once properly normalized, the intermittency in NSTX falls in similar electrostatic instability regimes as seen in other devices. The L-H transition causes a drop in the intermittent filaments velocity, amplitude and number in the SOL, resulting in reduced outward transport away from the edge and a less dense SOL.

  17. NSTX Weekly Report (Apr. 9, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    under investigation. Engineering Operations (A. von Halle, C. Neumeyer) NSTX experimental operationsNSTX Weekly Report (Apr. 9, 2010) FY 2010 NSTX plasma operations Planned: Total - 15 run weeks collaboration with C-Mod and DIII-D staff) delivered to the DoE. In NSTX, preparation for operation

  18. NSTX Upgrade Project Execution Plan NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Upgrade Project Federal Project Director, SC-PSO Administrative Change Approved by Office, ou=DOE-PSO, email=aindelicato@pppl.gov, c=US Date: 2012.10.15 09:41:43 -04'00' #12;NSTX Upgrade Description of Changes A 1/11/10 PPEP Initial Issue by PPPL & PSO, but not approved by OFES B 4/5/10 PPEP Cost

  19. Progress in understanding the enhanced pedestal H-mode in NSTX

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gerhardt, S. P.; Canik, J. M.; Maingi, R.; Battaglia, D.; Bell, R. E.; Guttenfelder, W.; LeBlanc, B. P.; Smith, D. R.; Yuh, H.; Sabbagh, S.

    2014-08-01

    The paper describes the enhanced pedestal (EP) H-mode observed in the National Spherical Torus Experiment (NSTX). The defining characteristics of EP H-mode are given, namely i)transition after the L- to H-mode transition, ii) region of very steep ion temperature gradient, and iii) associated region of strong rotational shear. A newly observed long-pulse EP H-mode example shows quiescent behavior for as long as the heating and current drive sources are maintained. Cases are shown where the region of steep ion temperature gradient is located at the very edge, and cases where it is shifted up to 10 cm inward from themore »plasma edge; these cases are united by a common dependence of the ion temperature gradient on the toroidal rotation frequency shear. EP H-mode examples have been observed across a wide range of q95 and pedestal collisionality. No strong changes in the fluctuation amplitudes have been observed following the eP H-mode transition, and transport analysis indicates that the ion t hermal transport is comparable to or less than anticipated from a simple neoclassical transport model. Cases are shown where EP H-modes were reliably generated, through these low-q95 examples were difficult to sustain. A case where an externally triggered ELM precipitates the transition to EP H-mode is also shown, though an initial experiment designed to trigger EP-H-modes in this fashion was successful.« less

  20. Progress In Understanding The Enhanced Petestal H-mode In NSTX

    SciTech Connect (OSTI)

    Gerhardt, S. P.; Canik, J. M.; Maingi, R.; Battaglia, D.; Bell, R. E.; Guttenfelder, W.; LeBlanc, B. P.; Smith, D. R.; Yuh, H.; Sabbagh, S.

    2014-06-26

    ThIS paper describes the enhanced pedestal (EP) H-mode observed in the National Spherical Torus Experiment (NSTX). The defining characteristics of EP H-mode are given, namely i)transition after the L- to H-mode transition, ii) region of very steep ion temperature gradient, and iii) associated region of strong rotational shear. A newly observed long-pulse EP H-mode example shows quiescent behavior for as long as the heating and current drive sources are maintained. Cases are shown where the region of steep ion temperature gradient is located at the very edge, and cases where it is shifted up to 10 cm inward from the plasma edge; these cases are united by a common dependence of the ion temperature gradient on the toroidal rotation frequency shear. EP H-mode examples have been observed across a wide range of q95 and pedestal collisionality. No strong changes in the fluctuation amplitudes have been observed following the eP H-mode transition, and transport analysis indicates that the ion t hermal transport is comparable to or less than anticipated from a simple neoclassical transport model. Cases are shown where EP H-modes were reliably generated, through these low-q95 examples were difficult to sustain. A case where an externally triggered ELM precipitates the transition to EP H-mode is also shown, though an initial experiment designed to trigger EP-H-modes in this fashion was successful.

  1. Progress in understanding the enhanced pedestal H-mode in NSTX

    SciTech Connect (OSTI)

    Gerhardt, S. P.; Canik, J. M.; Maingi, R.; Battaglia, D.; Bell, R. E.; Guttenfelder, W.; LeBlanc, B. P.; Smith, D. R.; Yuh, H.; Sabbagh, S.

    2014-08-01

    The paper describes the enhanced pedestal (EP) H-mode observed in the National Spherical Torus Experiment (NSTX). The defining characteristics of EP H-mode are given, namely i)transition after the L- to H-mode transition, ii) region of very steep ion temperature gradient, and iii) associated region of strong rotational shear. A newly observed long-pulse EP H-mode example shows quiescent behavior for as long as the heating and current drive sources are maintained. Cases are shown where the region of steep ion temperature gradient is located at the very edge, and cases where it is shifted up to 10 cm inward from the plasma edge; these cases are united by a common dependence of the ion temperature gradient on the toroidal rotation frequency shear. EP H-mode examples have been observed across a wide range of q95 and pedestal collisionality. No strong changes in the fluctuation amplitudes have been observed following the eP H-mode transition, and transport analysis indicates that the ion t hermal transport is comparable to or less than anticipated from a simple neoclassical transport model. Cases are shown where EP H-modes were reliably generated, through these low-q95 examples were difficult to sustain. A case where an externally triggered ELM precipitates the transition to EP H-mode is also shown, though an initial experiment designed to trigger EP-H-modes in this fashion was successful.

  2. NSTX Tangential Divertor Camera

    SciTech Connect (OSTI)

    A.L. Roquemore; Ted Biewer; D. Johnson; S.J. Zweben; Nobuhiro Nishino; V.A. Soukhanovskii

    2004-07-16

    Strong magnetic field shear around the divertor x-point is numerically predicted to lead to strong spatial asymmetries in turbulence driven particle fluxes. To visualize the turbulence and associated impurity line emission near the lower x-point region, a new tangential observation port has been recently installed on NSTX. A reentrant sapphire window with a moveable in-vessel mirror images the divertor region from the center stack out to R 80 cm and views the x-point for most plasma configurations. A coherent fiber optic bundle transmits the image through a remotely selected filter to a fast camera, for example a 40500 frames/sec Photron CCD camera. A gas puffer located in the lower inboard divertor will localize the turbulence in the region near the x-point. Edge fluid and turbulent codes UEDGE and BOUT will be used to interpret impurity and deuterium emission fluctuation measurements in the divertor.

  3. Development of a radio frequency ion source with multi-helicon plasma injectors for neutral beam injection system of Versatile Experiment Spherical Torus

    SciTech Connect (OSTI)

    Choe, Kyumin; Jung, Bongki; Chung, Kyoung-Jae; Hwang, Y. S.; Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744

    2014-02-15

    Despite of high plasma density, helicon plasma has not yet been applied to a large area ion source such as a driver for neutral beam injection (NBI) system due to intrinsically poor plasma uniformity in the discharge region. In this study, a radio-frequency (RF) ion source with multi-helicon plasma injectors for high plasma density with good uniformity has been designed and constructed for the NBI system of Versatile Experiment Spherical Torus at Seoul National University. The ion source consists of a rectangular plasma expansion chamber (120 × 120 × 120 mm{sup 3}), four helicon plasma injectors with annular permanent magnets and RF power system. Main feature of the source is downstream plasma confinement in the cusp magnetic field configuration which is generated by arranging polarities of permanent magnets in the helicon plasma injectors. In this paper, detailed design of the multi-helicon plasma injector and plasma characteristics of the ion source are presented.

  4. News | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Torus Experiment-Upgrade. Technicians inspect the new center stack that forms the heart of the NSTX-U. The new neutral beam box arrives in the NSTX-U test cell. The NSTX-U...

  5. NSTX Upgrade Project Execution Plan NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    _____________________________ Manager, SC-PSO _____________________________ J. Makiel NSTX Upgrade Project Federal Project Director, SC-PSO Description of Changes A 1/11/10 PPEP Initial Issue by PPPL & PSO, but not approved by OFES B 4/5/10 PPEP Cost

  6. NSTX-U NSTX-U PAC-36 1 PAC-36 Agenda June 23, 2015

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    HHFW System 1st NBI 2nd NBI NSTX-U · 1 shot away from 1st plasma attempt, had arc on OH water cooling-40 minutes #12;M. Ono NSTX-U PAC-36 June 23, 2015NSTX-U NSTX-U OH Arc Incident / Facility Status Masa Ono, we were performing test shots in preparation for the CD-4 KPP attempt when an arc occurred. 3

  7. NSTX Weekly Report (Mar. 5, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    `Demonstration of Tokamak Ohmic Flux Saving by Transient Coaxial Helicity Injection on NSTX' by R. Raman et al

  8. NSTX Weekly Report (November 12, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . The invited talks were: "Demonstration of Inductive Flux Saving by Transient CHI on NSTX" by R. Raman (U

  9. Physics design of the NSTX UpgradePhysics design of the NSTX Upgrade Jon Menard, PPPL

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    engineering design of the upgrade, systematic free-boundary equilibrium calculations have been performedPhysics design of the NSTX UpgradePhysics design of the NSTX Upgrade Jon Menard, PPPL NSTX Program Dominion U ORNL PPPL PSI Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Irvine UCLA UCSD U Colorado

  10. NSTX Upgrade Project Final Design Review June 22 -24, 2011 1 NSTX Supported by

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Upgrade Project ­ Final Design Review June 22 - 24, 2011 1 NSTX Supported by College W Photonics New York U Old Dominion U ORNL PPPL PSI Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Plasma Physics Laboratory NSTX Upgrade Project Final Design Review LSB, B318 June 22-24, 2011 1 Monday

  11. NSTX Weekly Report (May 14, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Weekly Report (May 14, 2010) FY 2010 NSTX plasma operations Planned: Total - 15 run weeks technology development laboratories. (R. Kaita) Engineering Operations (A. von Halle, C. Neumeyer) The extended NSTX maintenance period to address an OH coil lead water leak continued this week

  12. NSTX Weekly Report (May 7, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    presentations. (J. Menard) Engineering Operations (A. von Halle, C. Neumeyer) The extended NSTX maintenance week during this extended maintenance period. Research Operations (M. Bell) Boundary Physics OperationsNSTX Weekly Report (May 7, 2010) FY 2010 NSTX plasma operations Planned: Total - 15 run weeks (Base

  13. NSTX Weekly Report (Apr. 30, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . Kaye) Engineering Operations (A. von Halle, C. Neumeyer) The extended NSTX maintenance period week during this extended maintenance period. Research Operations (M. Bell) Boundary Physics OperationsNSTX Weekly Report (Apr. 30, 2010) FY 2010 NSTX plasma operations Planned: Total - 15 run weeks

  14. NSTX Upgrade Project STRUCTURAL CALCULATION OF THE TF FLAG KEY

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    source of design information including computer program titles and revision levels.) 1] NSTX-CALC-13] NSTX Structural Design Criteria Document, I. Zatz [3] NSTX Design Point June 2010 http://www.pppl.gov/~neumeyer/NSTX_CSU/Design blade due to the OOP torque. 3.)The shear strength of the epoxy used to bond the CRES insert into the G

  15. Health and Safety Plan for NSTX Upgrade Project Tasks

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Health and Safety Plan for NSTX Upgrade Project Tasks in the NSTX Test Cell PRINCETON PLASMA....~_____...L....,L....q..l:::::.......:.J Larry Dudek, NSTX Center Stack Manager Reviewed by: I( Jer evine, Environment, Safety, Health and S This document describes the structure and implementation of the Health and Safety Plan for the NSTX Upgrade

  16. NSTX Plasma Response to Lithium Coated Divertor

    SciTech Connect (OSTI)

    H.W. Kugel, M.G. Bell, J.P. Allain, R.E. Bell, S. Ding, S.P. Gerhardt, M.A. Jaworski, R. Kaita, J. Kallman, S.M. Kaye, B.P. LeBlanc, R. Maingi, R. Majeski, R. Maqueda, D.K. Mansfield, D. Mueller, R. Nygren, S.F. Paul, R. Raman, A.L. Roquemore, S.A. Sabbagh, H. Schneider, C.H. Skinner, V.A. Soukhanovskii, C.N. Taylor, J.R. Timberlak, W.R. Wampler, L.E. Zakharov, S.J. Zweben, and the NSTX Research Team

    2011-01-21

    NSTX experiments have explored lithium evaporated on a graphite divertor and other plasma facing components in both L- and H- mode confinement regimes heated by high-power neutral beams. Improvements in plasma performance have followed these lithium depositions, including a reduction and eventual elimination of the HeGDC time between discharges, reduced edge neutral density, reduced plasma density, particularly in the edge and the SOL, increased pedestal electron and ion temperature, improved energy confinement and the suppression of ELMs in the H-mode. However, with improvements in confinement and suppression of ELMs, there was a significant secular increase in the effective ion charge Zeff and the radiated power in H-mode plasmas as a result of increases in the carbon and medium-Z metallic impurities. Lithium itself remained at a very low level in the plasma core, <0.1%. Initial results are reported from operation with a Liquid Lithium Divertor (LLD) recently installed.

  17. Lithium Wall Conditioning And Surface Dust Detection On NSTX

    SciTech Connect (OSTI)

    Skinner, C H; Bell, M G; Friesen, F.Q.L.; Heim, B; Jaworski, M A; Kugel, H; Maingi, R; Rais, B

    2011-05-23

    Lithium evaporation onto NSTX plasma facing components (PFC) has resulted in improved energy confinement, and reductions in the number and amplitude of edge-localized modes (ELMs) up to the point of complete ELM suppression. The associated PFC surface chemistry has been investigated with a novel plasma material interface probe connected to an in-vacuo surface analysis station. Analysis has demonstrated that binding of D atoms to the polycrystalline graphite material of the PFCs is fundamentally changed by lithium - in particular deuterium atoms become weakly bonded near lithium atoms themselves bound to either oxygen or the carbon from the underlying material. Surface dust inside NSTX has been detected in real-time using a highly sensitive electrostatic dust detector. In a separate experiment, electrostatic removal of dust via three concentric spiral-shaped electrodes covered by a dielectric and driven by a high voltage 3-phase waveform was evaluated for potential application to fusion reactors

  18. Lithium Surface Coatings for Improved Plasma Performance in NSTX

    SciTech Connect (OSTI)

    Kugel, H W; Ahn, J -W; Allain, J P; Bell, R; Boedo, J; Bush, C; Gates, D; Gray, T; Kaye, S; Kaita, R; LeBlanc, B; Maingi, R; Majeski, R; Mansfield, D; Menard, J; Mueller, D; Ono, M; Paul, S; Raman, R; Roquemore, A L; Ross, P W; Sabbagh, S; Schneider, H; Skinner, C H; Soukhanovskii, V; Stevenson, T; Timberlake, J; Wampler, W R

    2008-02-19

    NSTX high-power divertor plasma experiments have shown, for the first time, significant and frequent benefits from lithium coatings applied to plasma facing components. Lithium pellet injection on NSTX introduced lithium pellets with masses 1 to 5 mg via He discharges. Lithium coatings have also been applied with an oven that directed a collimated stream of lithium vapor toward the graphite tiles of the lower center stack and divertor. Lithium depositions from a few mg to 1 g have been applied between discharges. Benefits from the lithium coating were sometimes, but not always seen. These improvements sometimes included decreases plasma density, inductive flux consumption, and ELM frequency, and increases in electron temperature, ion temperature, energy confinement and periods of MHD quiescence. In addition, reductions in lower divertor D, C, and O luminosity were measured.

  19. Work Authorization Document NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    element includes refurbishment of a TFTR NBI and its relocation to the NSTX test cell. Included in this WBS element are the activities necessary to refurbish a TFTR Neutral Beam beamline for use on NSTX. This scope includes replacing copper impinged parts as required and refurbishment of the seals, thermocouple

  20. CTI in NSTX, Proposal for Compact Toroid Injection in NSTX

    SciTech Connect (OSTI)

    R. Raman

    2008-11-04

    This is the final Report summarizing the activities of the proposal to invetigate the potential of deep fueling a spherical torus or tokamak using high velocity injection of compact toroids.

  1. NSTX Disruption Simulations of Detailed Divertor and Passive Plate Models by Vector Potential Transfer from OPERA Global Analysis Results

    SciTech Connect (OSTI)

    P. H. Titus, S. Avasaralla, A.Brooks, R. Hatcher

    2010-09-22

    The National Spherical Torus Experiment (NSTX) project is planning upgrades to the toroidal field, plasma current and pulse length. This involves the replacement of the center-stack, including the inner legs of the TF, OH, and inner PF coils. A second neutral beam will also be added. The increased performance of the upgrade requires qualification of the remaining components including the vessel, passive plates, and divertor for higher disruption loads. The hardware needing qualification is more complex than is typically accessible by large scale electromagnetic (EM) simulations of the plasma disruptions. The usual method is to include simplified representations of components in the large EM models and attempt to extract forces to apply to more detailed models. This paper describes a more efficient approach of combining comprehensive modeling of the plasma and tokamak conducting structures, using the 2D OPERA code, with much more detailed treatment of individual components using ANSYS electromagnetic (EM) and mechanical analysis. This capture local eddy currents and resulting loads in complex details, and allows efficient non-linear, and dynamic structural analyses.

  2. Design and Construction of the NSTX Bakeout, Cooling and Vacuum Systems

    SciTech Connect (OSTI)

    L.E. Dudek; M. Kalish; R. Gernhardt; R.F. Parsells; W. Blanchard

    1999-11-01

    This paper will describe the design, construction and initial operation of the NSTX bakeout, water cooling and vacuum systems. The bakeout system is designed for two modes of operation. The first mode allows heating of the first wall components to 350 degrees C while the external vessel is cooled to 150 degrees C. The second mode cools the first wall to 150 degrees C and the external vessel to 50 degrees C. The system uses a low viscosity heat transfer oil which is capable of high temperature low pressure operation. The NSTX Torus Vacuum Pumping System (TVPS) is designed to achieve a base pressure of approximately 1x10 (superscript -8) Torr and to evacuate the plasma fuel gas loads in less than 5 minutes between discharges. The vacuum pumping system is capable of a pumping speed of approximately 3400 l/s for deuterium. The hardware consists of two turbo molecular pumps (TMPs) and a mechanical pump set consisting of a mechanical and a Roots blower pump. A PLC is used as the control system to provide remote monitoring, control and software interlock capability. The NSTX cooling water provides chilled, de ionized water for heat removal in the TF, OH and PF, power supplies, bus bar systems, and various diagnostics. The system provides flow monitoring via a PLC to prevent damage due to loss of flow.

  3. Comparison of Gas Puff Imaging Data in NSTX with the DEGAS 2 Simulation

    SciTech Connect (OSTI)

    Cao, B.; Stotler, D. P.; Zweben, S. J.; Bell, M.; Diallo, A.; Leblanc, B.

    2012-10-27

    Gas-Puff-Imaging (GPI) is a two dimensional diagnostic which measures the edge D? light emission from a neutral D2 gas puff nears the outer mid-plane of NSTX. DEGAS 2 is a 3-D Monte Carlo code used to model neutral transport and atomic physics in tokamak plasmas. In this paper we compare measurements of the D? light emission obtained by GPI on NSTX with DEGAS 2 simulations of D? light emission for specific experiments. Both the simulated spatial distribution and absolute intensity of the D? light emission agree well with the experimental data obtained between ELMs in H-mode.

  4. Comparison of Gas Puff Imaging Data in NSTX with the DEGAS 2 Simulation

    SciTech Connect (OSTI)

    Cao, B.; Stotler, D. P.; Zweben, S. J.; Bell, M.; Diallo, A.; Leblanc, B.

    2012-11-08

    Gas-Puff-Imaging (GPI) is a two dimensional diagnostic which measures the edge D? light emission from a neutral D2 gas puff nears the outer mid-plane of NSTX. DEGAS 2 is a 3-D Monte Carlo code used to model neutral transport and atomic physics in tokamak plasmas. In this paper we compare measurements of the D? light emission obtained by GPI on NSTX with DEGAS 2 simulations of D? light emission for specific experiments. Both the simulated spatial distribution and absolute intensity of the D? light emission agree well with the experimental data obtained between ELMs in H-mode. __________________________________________________

  5. Spherical torus fusion reactor

    DOE Patents [OSTI]

    Martin Peng, Y.K.M.

    1985-10-03

    The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

  6. NSTX Computing and Controls Paul Sichta

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Generator Neutral Beam Power RF Generators NSTX Test Cell Control Room Field Coil Power Conversion Water Cell computer hardware failures Adnaco PCI fiber optic extender all fiber network NSTXNSTX EPICS

  7. Princeton Plasma Physics Lab - NSTX-U

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgram GuidelinesThousandnstx-u The National Spherical Torus Experiment

  8. NSTX Weekly Report (July 9, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    operations were suspended this past week to investigate an elevated electrical leakage current through the OHNSTX Weekly Report (July 9, 2010) FY 2010 NSTX plasma operations Planned: Total - 15 run weeks: ARRA -1.01run week and 171 plasma shots Engineering Operations (A. von Halle, C. Neumeyer) NSTX

  9. NSTX Weekly Report (Feb. 5, 2009) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Weekly Report (Feb. 5, 2009) FY 2010 NSTX plasma operations Planned: Total - 15 run weeks (Base - 14 run weeks, ARRA - 1 run week) Completed: 0 run week and 0 plasma shot Yevgeny Raitses attended the Workshop on Unipolar Arcs in Argonne, National Laboratory, January 29. He gave a talk entitled

  10. NSTX Weekly Report (August 6, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . Maingi gave a seminar at MIT on 8/2/10: "Triggered Enhancement Confinement and Pedestal Expansion in NSTX of Pilot Plant Studies and contributions to FNST" and co-chaired a session "FNSF Testing Strategy divertor - a personal perspective", and "Recent NSTX experimental results related to lithium." R. Kaita

  11. NSTX Weekly Report (December 3, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    installations for the new MSE-LIF diagnostic and for the upgrade to add a second Switching Power Amplifier leave. He will be collaborating on NSTX including the NSTX plasma operations and the pilot plant design, and maintenance of the RWM coil grounding switch in the test cell is nearing completion. Electricians continued

  12. NSTX Weekly Report (May 28, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    in NSTX" by J.-W. Ahn (ORNL). Both talks were well received. Fourteen poster presentations were given Lithium Evaporation onto the NSTX Vessel Walls" by D. Stotler, "Macroscopic Motion of Liquid Metal Plasma operations resumed this past week after completion of combined field power testing, leading to the successful

  13. NSTX Weekly Report (Jan. 15, 2009) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    preparations to close and pump-down the NSTX vacuum vessel. Some rework and testing of the Beam Emission duct is scheduled for next week, and will be followed by vessel pump-down. Access to the NSTX test cell presented, as well as the first analysis of the heat flux profiles from ELM types. (R. Maingi) · The paper

  14. Data Analysis Tools for NSTX-U Physics Meeting

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    LLC #12;NSTX-U Monday Physics Meeting­ Data Analysis Tools, Bill Davis (8/26/2013) 2 Overview ·Web/26/2013) 3 Web Tool access at http://nstx.pppl.gov/nstx/Software/WebTools Designed for ease-of-use: #12;NSTX-U Monday Physics Meeting­ Data Analysis Tools, Bill Davis (8/26/2013) 4 Access to Plotting Web Tools #12

  15. Implementation of BN Control in the National Spherical Torus...

    Office of Scientific and Technical Information (OSTI)

    the normalized B in the National Spherical Torus Experiment M. Ono, et al., Nuclear Fusion 40, 557 (2000). A PID operator is applied to the difference between the present value...

  16. Health and Safety Plan for NSTX Upgrade Project Tasks

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Draft 0 6/17/11 1 Health and Safety Plan for NSTX Upgrade Project Tasks in the NSTX Test Cell: _____________________________________________________________ Jerry Levine, Environment, Safety, Health and Security Head Reviewed by describes the structure and implementation of the Health and Safety Plan for the NSTX Upgrade Project work

  17. Spherical torus fusion reactor

    DOE Patents [OSTI]

    Peng, Yueng-Kay M. (Oak Ridge, TN)

    1989-01-01

    A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

  18. Diagnostic options for radiative divertor feedback control on NSTX-U

    SciTech Connect (OSTI)

    Soukhanovskii, V. A.; McLean, A. G. [Lawrence Livermore National Laboratory, Livermore, California, 94550 (United States); Gerhardt, S. P.; Kaita, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Raman, R. [University of Washington, Seattle, Washington 98195 (United States)

    2012-10-15

    A radiative divertor technique is used in present tokamak experiments and planned for ITER to mitigate high heat loads on divertor plasma-facing components (PFCs) to prevent excessive material erosion and thermal damage. In NSTX, a large spherical tokamak with lithium-coated graphite PFCs and high divertor heat flux (q{sub peak} Less-Than-Or-Slanted-Equal-To 15 MW/m{sup 2}), radiative divertor experiments have demonstrated a significant reduction of divertor peak heat flux simultaneously with good core H-mode confinement using pre-programmed D{sub 2} or CD{sub 4} gas injections. In this work diagnostic options for a new real-time feedback control system for active radiative divertor detachment control in NSTX-U, where steady-state peak divertor heat fluxes are projected to reach 20-30 MW/m{sup 2}, are discussed. Based on the NSTX divertor detachment measurements and analysis, the control diagnostic signals available for NSTX-U include divertor radiated power, neutral pressure, spectroscopic deuterium recombination signatures, infrared thermography of PFC surfaces, and thermoelectric scrape-off layer current. In addition, spectroscopic 'security' monitoring of possible confinement or pedestal degradation is recommended. These signals would be implemented in a digital plasma control system to manage the divertor detachment process via an actuator (impurity gas seeding rate).

  19. Overview of Innovative PMI Research on NSTX-U and Associated PMI Facilities at PPPL

    SciTech Connect (OSTI)

    M. Ono, M. Jaworski, R. Kaita, C. N. Skinner, J.P. Allain, R. Maingi, F. Scotti, V.A. Soukhanovskii, and the NSTX-U Team

    2012-09-19

    Developing a reactor compatible divertor and managing the associated plasma material interaction (PMI) has been identified as a high priority research area for magnetic confinement fusion. Accordingly on NSTXU, the PMI research has received a strong emphasis. With ~ 15 MW of auxiliary heating power, NSTX-U will be able to test the PMI physics with the peak divertor plasma facing component (PFC) heat loads of up to 40-60 MW/m2 . To support the PMI research, a comprehensive set of PMI diagnostic tools are being implemented. The snow-flake configuration can produce exceptionally high divertor flux expansion of up to ~ 50. Combined with the radiative divertor concept, the snow-flake configuration has reduced the divertor heat flux by an order of magnitude in NSTX. Another area of active PMI investigation is the effect of divertor lithium coating (both in solid and liquid phases). The overall NSTX lithium PFC coating results suggest exciting opportunities for future magnetic confinement research including significant electron energy confinement improvements, Hmode power threshold reduction, the control of Edge Localized Modes (ELMs), and high heat flux handling. To support the NSTX-U/PPPL PMI research, there are also a number of associated PMI facilities implemented at PPPL/Princeton University including the Liquid Lithium R&D facility, Lithium Tokamak Experiment, and Laboratories for Materials Characterization and Surface Chemistry.

  20. NSTX Weekly Report (Feb. 19, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ) - The electrical assembly of the first Bay F unit (F1) was completed. Preparations for F1 leak checking started the talk "Progress in Developing Advanced Spherical Tokamak Scenarios in NSTX." (R. Kaita) Engineering

  1. Overview of the Initial NSTX Experimental Results

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . Taylor, J.R. Wilson,P. Efthimion, J. Hosea, R. Goldston, S. C. Jardin,, R. Hawryluck, K. Hill, H. Ji, R, 2000 #12;NSTX Team Members M. Ono, M. Bell, R. E. Bell, M. Bitter, D. Darrow, D. Gates, S. M. Kaye, R. Davis, L. Dudek, R. Ellis, E. Fredd, T. Gibney, R. E. Hatcher, M. Kalish, McCormack, R. Marsala, C

  2. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Research Operations Chit Review Board (designated by Run Coordinator) MINOR MODIFICATIONS (Approved-mounted Langmuir probe and two small magnetic coils for Br and Bz measurements. The assembly is mounted measurements [6, 7] using the supersonic Releigh-Pitot law. Initial NSTX SGI results obtained in the end of FY

  3. NSTX Report on FES Joint Facilities Research Milestone 2010

    SciTech Connect (OSTI)

    Maingi, R.; Ahn, J- W.; Gray, T. K.; McLean, A. G.; Soukhanovskii, V. A.

    2011-03-24

    Annual Target: Conduct experiments on major fusion facilities to improve understanding of the heat transport in the tokamak scrape-off layer (SOL) plasma, strengthening the basis for projecting divertor conditions in ITER. The divertor heat flux profiles and plasma characteristics in the tokamak scrape-off layer will be measured in multiple devices to investigate the underlying thermal transport processes. The unique characteristics of C-Mod, DIII-D, and NSTX will enable collection of data over a broad range of SOL and divertor parameters (e.g., collisionality ?*, beta ?, parallel heat flux q||, and divertor geometry). Coordinated experiments using common analysis methods will generate a data set that will be compared with theory and simulation.

  4. Physics Motivation for NSTXPhysics Motivation for NSTX UpgradeUpgrade Jon Menard and Masa Ono

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Physics Motivation for NSTXPhysics Motivation for NSTX UpgradeUpgrade Jon Menard and Masa Ono NSTX CEA, Cadarache IPP, Jülich IPP, Garching ASCR, Czech Rep U Quebec #12;NSTXNSTX Physics Motivation ARIES-ST #12;NSTXNSTX Physics Motivation for NSTX Upgrade 3Fall 2009 NSTX Research Priorities: · Full

  5. Associate Research Physicist (Post Doc, Experimental Research...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Spherical Torus Experiment Upgrade (NSTX-U). For present and future magnetic fusion devices to operate reliably a high plasma pressure and high power density for...

  6. Disruptions, Disruptivity, and Safer Operating Windows in the...

    Office of Scientific and Technical Information (OSTI)

    in the high- N National Spherical Torus Experiment (NSTX) M. Ono, et al. Nuclear Fusion 40, 557 (2000). While the overall disruption rate is rather high, configurations with...

  7. Version 3 June 20, 2015 NSTX Upgrade Program Letter

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Innovative Diagnostics for FY 2016-2018 Introduction This NSTX Upgrade (NSTX-U)1 Program Letter provides for reducing cost, risk, and development time for practical fusion energy. The ST appears particularly, with its unique properties, thus extends and complements the higher aspect ratio, lower T tokamak

  8. NSTX Upgrade FDR Calculation Executive Summaries

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    in format, but it should give an indication of the scope of the analysis work performed to support the NSTX-CALC-12-04-00 PF2 / PF3 Bolting, Bracket, and weld Stress P. Titus 1.1.2 NSTXU-CALC-12-05-00 PF4 and PF5 Support Analysis P. Titus 1.1.2 NSTXU-CALC-12-06-00 Aluminum Block (To Be Revised by Pete T.) P. Titus 1

  9. NSTX Upgrade FDR Calculation Executive Summaries

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    performed to support the NSTX Upgrade design effort. Some, but not most, have been reviewed and signed.1.2 NSTXU-CALC-12-04-00 PF2 / PF3 Bolting, Bracket, and weld Stress P. Titus I.Zatz 1.1.2 NSTXU-CALC-12-05-00 PF4 and PF5 Support Analysis P. Titus I.Zatz 1.1.2 NSTXU-CALC-12-06-00 Aluminum Block (To Be Revised

  10. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Myra, J. R. [Lodestar Research Corporation, Boulder, CO (United States); Russell, D. A. [Lodestar Research Corporation, Boulder, CO (United States); D'Ippolito, D. A. [Lodestar Research Corporation, Boulder, CO (United States); Ahn, J- W [Oak Ridge National Lab., TN (United States); Maingi, R. [Oak Ridge National Lab., TN (United States); Maqueda, R. J. [Princeton Plasma Physics Lab., NJ (United States); Lundberg, D. P. [Princeton Plasma Physics Lab., NJ (United States); Stotler, D. P. [Princeton Plasma Physics Lab., NJ (United States); Zweben, S. J. [Princeton Plasma Physics Lab., NJ (United States); Boedo, J. [Univ. of California at San Diego, CA (United States); Umansky, M. [Lawrence Livermore National Lab., Livermore, CA (United States)

    2011-01-10

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from the simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) [S. M. Kaye, et al., Phys. Plasmas 8, 1977 (2001)] to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat flux width for the low power H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL heat flux width observed experimentally in higher power discharges. Intermittent separatrix spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping vs. emission are discussed.

  11. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Myra, J. R.; Russell, D. A.; D’Ippolito, D. A.; Ahn, J.-W.; Maingi, R.; Maqueda, R. J.; Lundberg, D. P.; Stotler, D. P.; Zweben, S. J.; Boedo, J.; et al

    2011-01-01

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from themore »simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat flux width for the low power H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL heat flux width observed experimentally in higher power discharges. Intermittent separatrix spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping vs. emission are discussed.« less

  12. Progress in Simulating Turbulent Electron Thermal Transport in NSTX

    SciTech Connect (OSTI)

    Guttenfelder, Walter; Kaye, S. M.; Ren, Y.; Bell, R. E.; Hammett, G. W.; LeBlanc, B. P.; Mikkelsen, D. R. [Princeton Plasma Physics Lab., Princeton, NJ (United States); Peterson, J. L.; Nevins, W. M. [Lawrence Livermore National Lab., Livermore, CA (United States); Candy, J. [General Atomics, San Diego, CA (United States); Yuh, H. [Nova Photonics, Princeton, NJ (United States)

    2013-07-17

    Nonlinear simulations based on multiple NSTX discharge scenarios have progressed to help differentiate unique instability mechanisms and to validate with experimental turbulence and transport data. First nonlinear gyrokinetic simulations of microtearing (MT) turbulence in a high-beta NSTX H-mode discharge predict experimental levels of electron thermal transport that are dominated by magnetic flutter and increase with collisionality, roughly consistent with energy confinement times in dimensionless collisionality scaling experiments. Electron temperature gradient (ETG) simulations predict significant electron thermal transport in some low and high beta discharges when ion scales are suppressed by E x B shear. Although the predicted transport in H-modes is insensitive to variation in collisionality (inconsistent with confinement scaling), it is sensitive to variations in other parameters, particularly density gradient stabilization. In reversed shear (RS) Lmode discharges that exhibit electron internal transport barriers, ETG transport has also been shown to be suppressed nonlinearly by strong negative magnetic shear, s<<0. In many high beta plasmas, instabilities which exhibit a stiff beta dependence characteristic of kinetic ballooning modes (KBM) are sometimes found in the core region. However, they do not have a distinct finite beta threshold, instead transitioning gradually to a trapped electron mode (TEM) as beta is reduced to zero. Nonlinear simulations of this "hybrid" TEM/KBM predict significant transport in all channels, with substantial contributions from compressional magnetic perturbations. As multiple instabilities are often unstable simultaneously in the same plasma discharge, even on the same flux surface, unique parametric dependencies are discussed which may be useful for distinguishing the different mechanisms experimentally.

  13. NSTX Weekly Report (June 04, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ,1028,1027, 1064, and 1043. - LITER units F1 and K1 were craned from the Test Cell to the South High Bay for reloading. - LITER unit F1 was reloaded with 84.70 grams of lithium. · Liquid Lithium Divertor Diagnostics it runs. Engineering Operations (A. von Halle, C. Neumeyer) NSTX plasma operations continued this past

  14. NSTX Weekly Report (September 17, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . Kallman, "First Real-Time Detection of Surface Dust in a Tokamak" by C. Skinner, "Tungsten Transport a master's research project on dust detection in tokamaks. He performed calibrations of the electrostatic on NSTX. He also developed and tested a helium puffing system to remove residual dust from the detector

  15. NSTX Weekly Report (December 10, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    cable installations for the addition of the second Switching Power Amplifier system. Access to the NSTX, helium and water piping modifications needed for the new MSE-LIF diagnostic continued, as well as power (LLD) - Design and planning work started for fabricating and testing an upgraded ceramic break

  16. NSTX Weekly Report (June 11, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    heating, as well as dual probe lithium evaporation. The lithium (LITER) probe in the Bay F #12;position vacuum vessel. Operations resumed on Friday June 11 after the elevated leakage current issue was cleared. Also this week, a peer review of the new tangential FIDA diagnostic was held. Access to the NSTX test

  17. NSTX Weekly Report (Jan. 08, 2009) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    joint resistances. Final wipe-downs of the NSTX vessel interior are in progress, as well-operational testing of the LLD heating system, and a 200 Amp test of the TF coil system to measure and document TF as the blackening of select in-vessel surfaces. The final inspection and photography of the vessel interior

  18. NSTX Weekly Report (November 5, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    lithium dropper on EAST. An initial test of lithium dropper on EAST has gone smoothly. (D. Mansfield) Run by the hot air heater well above the lithium melting temperature of 180°C with less than half. von Halle, C. Neumeyer) The NSTX outage began this week with partial vents of the vessel in argon

  19. NSTX Weekly Report (July 23, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    insulation, and the integrated system testing for restoring TF/OH operations. Access to the NSTX test cell building. Research Operations (M. Bell) Boundary Physics Operations (H. Kugel) Alignments and spatial and six old optical fibers viewing the LLD. (V. Soukhanovskii) Testing of a new automated filling

  20. Solenoid-free Plasma Start-up in NSTX using Transient CHI

    SciTech Connect (OSTI)

    Raman, R; Jarboe, T; Nelson, B; Mueller, D; Soukhanovskii, V A

    2009-01-05

    Experiments in NSTX have now demonstrated the coupling of toroidal plasmas produced by the technique of Coaxial Helicity Injection (CHI) to inductive sustainment and ramp-up of the toroidal plasma current. In these discharges, the central Ohmic transformer was used to apply an inductive loop voltage to discharges with a toroidal current of about 100 kA created by CHI. The coupled discharges have ramped up to >700 kA and transitioned into an H-mode demonstrating compatibility of this startup method with conventional operation. The electron temperature in the coupled discharges reached over 800 eV and the resulting plasma had low inductance, which is preferred for long-pulse high performance discharges. These results from NSTX in combination with the previously obtained record 160 kA non-inductively-generated startup currents in an ST or tokamak in NSTX demonstrate that CHI is a viable solenoid-free plasma startup method for future STs and tokamaks.

  1. Disruptions, Disruptivity, and Safer Operating Windows in the High-? Spherical Torus NSTX

    SciTech Connect (OSTI)

    Brown, T; Goldston, R J; El-Guebaly, L; Kessel, C; Neilson, G H; Malang, S; Menard, J E; Prager, S; Scott, S; Titus, P; Waganer, L

    2012-09-26

    A fusion pilot plant study was initiated to clarify the development needs in moving from ITER to a first of a kind fusion power plant. The mission of the pilot plant was set to encompass component test and fusion nuclear science missions yet produce net electricity with high availability in a device designed to be prototypical of the commercial device. The objective of the study was to evaluate three different magnetic configuration options, the advanced tokamak (AT), spherical tokamak (ST) and compact stellarator (CS) in an effort to establish component characteristics, maintenance features and the general arrangement of each candidate device. With the move to look beyond ITER the fusion community is now beginning to embark on DEMO reactor studies with an emphasis on defining configuration arrangements that can meet a high availability goal. This paper reviews the AT pilot plant design, detailing the selected maintenance approach, the device arrangement and sizing of the in-vessel components. Details of interfacing auxiliary systems and services that impact the ability to achieve high availability operations will also be discussed.

  2. Detection of Disruptions in the High-β Spherical Torus NSTX (Technical

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interactionCrystalDesigning aDesignsfrom(Patent)Report)

  3. Detection of Disruptions in the High-β Spherical Torus NSTX (Technical

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnectlaser-solid interactionCrystalDesigning

  4. Efficient Subtorus Processor Allocation in a Multi-Dimensional Torus

    SciTech Connect (OSTI)

    Weizhen Mao; Jie Chen; William Watson

    2005-11-30

    Processor allocation in a mesh or torus connected multicomputer system with up to three dimensions is a hard problem that has received some research attention in the past decade. With the recent deployment of multicomputer systems with a torus topology of dimensions higher than three, which are used to solve complex problems arising in scientific computing, it becomes imminent to study the problem of allocating processors of the configuration of a torus in a multi-dimensional torus connected system. In this paper, we first define the concept of a semitorus. We present two partition schemes, the Equal Partition (EP) and the Non-Equal Partition (NEP), that partition a multi-dimensional semitorus into a set of sub-semitori. We then propose two processor allocation algorithms based on these partition schemes. We evaluate our algorithms by incorporating them in commonly used FCFS and backfilling scheduling policies and conducting simulation using workload traces from the Parallel Workloads Archive. Specifically, our simulation experiments compare four algorithm combinations, FCFS/EP, FCFS/NEP, backfilling/EP, and backfilling/NEP, for two existing multi-dimensional torus connected systems. The simulation results show that our algorithms (especially the backfilling/NEP combination) are capable of producing schedules with system utilization and mean job bounded slowdowns comparable to those in a fully connected multicomputer.

  5. Edge Turbulence Velocity Changes with Lithium Coating on NSTX

    SciTech Connect (OSTI)

    Cao, A.; Zweben, S. J.; Stotler, D. P.; Bell, M.; Diallo, A.; Kaye, S. M.; LeBlanc, B.

    2012-08-10

    Lithium coating improves energy confinement and eliminates edge localized modes in NSTX, but the mechanism of this improvement is not yet well understood. We used the gas-puff-imaging (GPI) diagnostic on NSTX to measure the changes in edge turbulence which occurred during a scan with variable lithium wall coating, in order to help understand the reason for the confinement improvement with lithium. There was a small increase in the edge turbulence poloidal velocity and a decrease in the poloidal velocity fluctuation level with increased lithium. The possible effect of varying edge neutral density on turbulence damping was evaluated for these cases in NSTX. __________________________________________________

  6. NSTX-U | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework usesofPublications The NREL windTeacher Programs PhotoVoylesNSTX-U

  7. The Condensate from Torus Knots

    E-Print Network [OSTI]

    A. Gorsky; A. Milekhin; N. Sopenko

    2015-06-22

    We discuss recently formulated instanton-torus knot duality in $\\Omega$-deformed 5D SQED on $\\mathbb{R}^4 \\times S^1$ focusing at the microscopic aspects of the condensate formation in the instanton ensemble. Using the chain of dualities and geometric transitions we embed the SQED with a surface defect into the $SU(2)$ SQCD with $N_f=4$ and identify the numbers $(n,m)$ of the torus $T_{n,m}$ knot as instanton charge and electric charge. The HOMFLY torus knot invariants in the fundamental representation provide entropic factor in the condensate of the massless flavor counting the degeneracy of the instanton--W-boson web with instanton and electric numbers $(n,m)$ but different spin and flavor content. Using the inverse geometrical transition we explain how our approach is related to the evaluation of the HOMFLY invariants in terms of Wilson loop in 3d CS theory. The reduction to 4D theory is briefly considered and some analogy with baryon vertex is conjectured.

  8. Fast 2-D Camera Control, Data Acquisition, and Database Techniques for Edge Studies on NSTX

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Fast 2-D Camera Control, Data Acquisition, and Database Techniques for Edge Studies on NSTX NSTX;NSTX-U 9th IAEA TM ­ Fast 2-D Camera Plasma Edge Studies (W. Davis) May 6-10, 2013 Abstract 2 Fast 2-D. This paper describes image analysis, database techniques, and visualization methods used to organize the fast

  9. Turbo Pump Magnetic Shielding Analysis NSTX-CALC-24-04-00

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Turbo Pump Magnetic Shielding Analysis NSTX-CALC-24-04-00 March 16, 2011 Prepared By the calculation is being performed.) To perform 3D analysis for the design of magnetic shield for the NSTX vacuum; and to extract Lorentz forces on the magnetic shield to ensure the shield is adequately supported References

  10. Supported by National Spherical Torus Experiment

    E-Print Network [OSTI]

    Transport? - Jenko, Doland,Hammet, PoP 8, 2001 JHU ETG's Role in ELM induced Cold Pulse S = - 0.3 kre ~ 0 Scaling, Electron Transport · Full set of diagnostics: including MSE for j(r) Unique Energetic Particle control coils on feedback performance #12;Significant Progress on Electron Heat Transport Physics

  11. Fuzzy Torus via q-Parafermion

    E-Print Network [OSTI]

    N. Aizawa; R. Chakrabarti

    2007-05-04

    We note that the recently introduced fuzzy torus can be regarded as a q-deformed parafermion. Based on this picture, classification of the Hermitian representations of the fuzzy torus is carried out. The result involves Fock-type representations and new finite dimensional representations for q being a root of unity as well as already known finite dimensional ones.

  12. Dynamics of the Disruption Halo Current Toroidal Asymmetry in NSTX

    SciTech Connect (OSTI)

    S.P. Gerhardt

    2012-09-27

    This paper describes the dynamics of disruption halo current non-axisymmetries in the lower divertor of the National Spherical Torus Experiment [M. Ono, et al. Nuclear Fusion 40, 557 (2000)]. While. The halo currents typically have a strongly asymmetric structure where they enter the divertor floor, and this asymmetry has been observed to complete up to 7 toroidal revolutions over the duration of the halo current pulse. However, the rotation speed and toroidal extend of the asymmetry can vary significantly during the pulse. The rotation speed, halo current pulse duration, and total number of revolutions tend to be smaller in cases with large halo currents. The halo current pattern is observed to become toroidally symmetric at the end of the halo current pulse. It is proposed that this symmeterization is due to the loss of most or all of the closed field line geometry in the final phase of the vertical displacement event.

  13. NSTX Program Governance, Research Support and Facility Operation

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    -30, 2008 College W&M Colorado Sch Mines Columbia U Comp-X General Atomics INEL Johns Hopkins U LANL LLNL, Cadarache IPP, Jülich IPP, Garching ASCR, Czech Rep U Quebec Supported by #12;NSTX 2009-13 5 year Plan · Milestone performance history · Scheduling operation, maintenance & upgrades · Managing environment, safety

  14. Analysis and Qualification Documentation The NSTX Upgrade Team

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Upgrade Final Design Review (6/22/2011) 4 NSTX CSU Calculation Index Historically What is Available Lodestar MIT Nova Photonics New York U ORNL PPPL Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Center Stack Upgrade Final Design Review (6/22/2011) Overview · This presentation is an overview

  15. NSTX Filament Preionization And Glow Discharge Cleaning Systems

    E-Print Network [OSTI]

    NSTX Filament Preionization And Glow Discharge Cleaning Systems H. W. Kugel, W. Blanchard, G. D filament preionization system that allowed D 2 and He Glow Discharge breakdowns at the actual operating pressure, voltage and current. The biased filament system was also operated continuously during ohmic

  16. NSTX Filament Preionization And Glow Discharge Cleaning Systems

    E-Print Network [OSTI]

    NSTX Filament Preionization And Glow Discharge Cleaning Systems H. W. Kugel, W. Blanchard, G. D filament preionization system that allowed D2 and He Glow Discharge breakdowns at the actual operating pressure, voltage and current. The biased filament system was also operated continuously during ohmic

  17. Implications of NSTX Lithium Results for Magnetic Fusion Research

    SciTech Connect (OSTI)

    M. Ono, M.G. Bell, R.E. Bell, R. Kaita, H.W. Kugel, B.P. LeBlanc, J.M. Canik, S. Diem, S.P.. Gerhardt, J. Hosea, S. Kaye, D. Mansfield, R. Maingi, J. Menard, S. F. Paul, R. Raman, S.A. Sabbagh, C.H. Skinner, V. Soukhanovskii, G. Taylor, and the NSTX Research Team

    2010-01-14

    Lithium wall coating techniques have been experimentally explored on NSTX for the last five years. The lithium experimentation on NSTX started with a few milligrams of lithium injected into the plasma as pellets and it has evolved to a lithium evaporation system which can evaporate up to ~ 100 g of lithium onto the lower divertor plates between lithium reloadings. The unique feature of the lithium research program on NSTX is that it can investigate the effects of lithium in H-mode divertor plasmas. This lithium evaporation system thus far has produced many intriguing and potentially important results; the latest of these are summarized in a companion paper by H. Kugel. In this paper, we suggest possible implications and applications of the NSTX lithium results on the magnetic fusion research which include electron and global energy confinement improvements, MHD stability enhancement at high beta, ELM control, H-mode power threshold reduction, improvements in radio frequency heating and non-inductive plasma start-up performance, innovative divertor solutions and improved operational efficiency.

  18. Internal transport barriers in NSTX H. Y. Yuh,1

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Internal transport barriers in NSTX H. Y. Yuh,1 R. E. Bell,2 J. C. Hosea,2 S. M. Kaye,2 B. P. Le General Atomics, San Diego, California 92186-5608, USA 4 University of California at Davis, Davis, California 95616, USA 5 POSTECH, Pohang 790-784, Korea (Dated: December 5, 2008) In the National Spherical

  19. Center Stack Casing Bellows NSTX-CALC-133-10

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    for the purchase of the bellows. Ultimately, the bellows manufacturer shall provide the qualification of the bellows. To ensure an adequate initial design, this calculation provides qualification of the acceptable. Reference calculation # NSTX CALC 11-01-00. · The upper bellows must support the seismic loads, Reference

  20. 3D TORUS V1.0

    Energy Science and Technology Software Center (OSTI)

    002440MLTPL00 3D Torus Routing Engine Module for OFA OpenSM v. 1.0  http://www.openfabrics.org/git?p=sashak/management.git;a=sum 

  1. Methanol in the L1551 Circumbinary Torus

    E-Print Network [OSTI]

    Glenn J. White; C. W. M. Fridlund; P. Bergman; A. Beardsmore; Rene Liseau; R. R. Phillips

    2006-09-25

    We report observations of gaseous methanol in an edge-on torus surrounding the young stellar object L1551 IRS5. The peaks in the torus are separated by ~ 10,000 AU from L1551 IRS5, and contain ~ 0.03 earth masses of cold methanol. We infer that the methanol abundance increases in the outer part of the torus, probably as a result of methanol evaporation from dust grain surfaces heated by the shock luminosity associated with the shocks associated with the jets of an externally located x-ray source. Any methanol released in such a cold environment will rapidly freeze again, spreading methanol throughout the circumbinary torus to nascent dust grains, planitesimals, and primitive bodies. These observations probe the initial chemical conditions of matter infalling onto the disk.

  2. Overview of theOverview of the NSTX Research Program for 2009NSTX Research Program for 2009--20132013

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    systems ­ Magnets B. Taming the plasma material Interface (PMI) ­ Plasma wall interactions ­ Plasma facing and Tokamak Research · Summary Outline:Outline: #12;NSTX 2009-13 5 year Plan ­ Program Overview (Menard) 3July. Complement tokamak physics and support ITER ­ Exploit unique ST features to improve tokamak understanding

  3. MHD Stability Research on NSTX and 3DMHD Stability Research on NSTX and 3D EffectsEffects

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    to static modes IPEC resonant field joins linear ne correlation from low- to increased- Ideal plasma, K. Tritz6, and the NSTX Research Team 1Department of Applied Physics, Columbia University, New York, NY 2Plasma Physics Laboratory, Princeton University, Princeton, NJ 3University of Rochester

  4. Compact 'diode-based' multi-energy soft x-ray diagnostic for NSTX

    SciTech Connect (OSTI)

    Tritz, K.; Clayton, D. J.; Stutman, D.; Finkenthal, M. [Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2012-10-15

    A novel and compact, diode-based, multi-energy soft x-ray (ME-SXR) diagnostic has been developed for the National Spherical Tokamak Experiment. The new edge ME-SXR system tested on NSTX consists of a set of vertically stacked diode arrays, each viewing the plasma tangentially through independent pinholes and filters providing an overlapping view of the plasma midplane which allows simultaneous SXR measurements with coarse sub-sampling of the x-ray spectrum. Using computed x-ray spectral emission data, combinations of filters can provide fast (>10 kHz) measurements of changes in the electron temperature and density profiles providing a method to 'fill-in' the gaps of the multi-point Thomson scattering system.

  5. TF INNER LEG COOLING USING FCOOL NSTX-CALC-132-10-00

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    1 NSTX TF INNER LEG COOLING USING FCOOL NSTX-CALC-132-10-00 October 20, 2010 Prepared By performed.) To estimate the cooling time and temperature of the TF inner leg during the cooling period square wave) of 8.5 seconds, the cooling takes 600-700 seconds. Cognizant Engineer's printed name

  6. Easy Web Interfaces to IDL Code for NSTX Data Analysis W. M. Davisa

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Easy Web Interfaces to IDL Code for NSTX Data Analysis W. M. Davisa * a Princeton Plasma Physics and debugging time. A variety of "Web Tools" for the analysis and display of raw and analyzed physics data are in use on NSTX [1], and new ones can be produced quickly from existing IDL [2] code. A Web Tool with only

  7. Influence of centrifugal effects on particle and momentum transport in NSTX R. Buchholz1

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Influence of centrifugal effects on particle and momentum transport in NSTX R. Buchholz1 , S experimentally relevant condi- tions in the spherical tokamak NSTX. The focus is specifically on the centrifugal, strengthened by centrifugal effects. This result is consistent with experimental measurements, and contradicts

  8. Spherical Torus Plasma Interactions with Large-Area Liquid Lithium Surfaces in CDX-U

    E-Print Network [OSTI]

    California at Los Angeles, University of

    Outside of Plasma" (DOLLOP) lithium wall conditioning experiments,[3] for example, in the Tokamak Fusion, introduction of large area lithium limiter targets and walls into existing tokamak facilities has not yet taken- 1 - Spherical Torus Plasma Interactions with Large-Area Liquid Lithium Surfaces in CDX-U R. KAITA

  9. Fast ion absorption of the high harmonic fast wave in the National Spherical Torus Experimenta...

    E-Print Network [OSTI]

    injection energy is sustained by the wave. In agreement with modeling, these experiments find the rfFast ion absorption of the high harmonic fast wave in the National Spherical Torus Experimenta... A Institute of Technology, Cambridge, Massachusetts 02139 Received 23 October 2003; accepted 19 December 2003

  10. Lithium Coatings on NSTX Plasma Facing Components and Its Effects On Boundary Control, Core Plasma Performance, and Operation

    SciTech Connect (OSTI)

    H.W.Kugel, M.G.Bell, H.Schneider, J.P.Allain, R.E.Bell, R Kaita, J.Kallman, S. Kaye, B.P. LeBlanc, D. Mansfield, R.E. Nygen, R. Maingi, J. Menard, D. Mueller, M. Ono, S. Paul, S.Gerhardt, R.Raman, S.Sabbagh, C.H.Skinner, V.Soukhanovskii, J.Timberlake, L.E.Zakharov, and the NSTX Research Team

    2010-01-25

    NSTX high-power divertor plasma experiments have used in succession lithium pellet injection (LPI), evaporated lithium, and injected lithium powder to apply lithium coatings to graphite plasma facing components. In 2005, following wall conditioning and LPI, discharges exhibited edge density reduction and performance improvements. Since 2006, first one, and now two lithium evaporators have been used routinely to evaporate lithium onto the lower divertor region at total rates of 10-70 mg/min for periods 5-10 min between discharges. Prior to each discharge, the evaporators are withdrawn behind shutters. Significant improvements in the performance of NBI heated divertor discharges resulting from these lithium depositions were observed. These evaporators are now used for more than 80% of NSTX discharges. Initial work with injecting fine lithium powder into the edge of NBI heated deuterium discharges yielded comparable changes in performance. Several operational issues encountered with lithium wall conditions, and the special procedures needed for vessel entry are discussed. The next step in this work is installation of a Liquid Lithium Divertor surface on the outer part of the lower divertor.

  11. NSTX-U IS ONE OF AN ELITE GROUP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework usesofPublications The NREL windTeacher Programs PhotoVoylesNSTX-U IS

  12. Results from the NSTX X-ray Crystal Spectrometer

    SciTech Connect (OSTI)

    M. Bitter; K. Hill; L. Roquemore; P. Beiersdorfer; D. Thorn; Ming Feng Gu

    2003-01-14

    A high-resolution X-ray crystal spectrometer has recently been installed at the National Spherical Torus Experiment to record the satellite spectra of helium-like argon, ArXVII, in the wavelength range from 3.94 to 4.00 {angstrom} for measurements of ion and electron temperatures, and measurements of the ionization equilibrium of argon, which is of interest for studies of ion transport. The instrument presently consists of a spherically bent quartz crystal and a conventional one-dimensional position-sensitive multi-wire proportional counter, but it will soon be upgraded to a new type of X-ray imaging crystal spectrometer by the installation of a large size (10 cm x 30 cm) two-dimensional position-sensitive detector that will allow us to obtain temporally and spatially resolved spectra from an 80 cm high cross-section of the plasma. In its present configuration, the spectrometer has been optimized for high throughput so that it is possible to record spectra with small statistical errors with a time resolution of 10 ms by adding only small, nonperturbing amounts of argon to the plasma. The spectrometer is most valuable for measurements of the ion temperature in the absence of a neutral beam in ohmically heated and radio-frequency heated discharges, when charge exchange recombination spectroscopy does not function. Electron temperature measurements from the satellite-to-resonance line ratios have been important for a quantitative comparison with (and verification of) the Thomson scattering data. The paper will describe the instrumental details of the present and future spectrometer configurations, and present recent experimental results.

  13. Princeton Plasma Physics Laboratory Procedure Title: Access to NSTX Experimental Areas

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX D-Site Caretaking Vacuum Computer Tritium Quality Assurance/Quality Control AC Power Maintenance Division Water Systems Neutral Beam (Heating Systems Branch of Electrical Engineering) Radiofrequency (Heating Systems Branch of Electrical Engineering) Diagnostics Environmental, Safety, & Health TRAINING

  14. Stabilization of electron-scale turbulence by electron density gradient in NSTX

    E-Print Network [OSTI]

    Ruiz Ruiz, Juan, S.M. Massachusetts Institute of Technology

    2015-01-01

    Microturbulence is present in all magnetic confinement fusion devices, and is believed to play a major role in driving anomalous transport levels that exceed neoclassical theory predictions. In NSTX, electron thermal ...

  15. Zero point energy on extra dimension: Noncommutative Torus

    E-Print Network [OSTI]

    S. Fabi; B. Harms; G. Karatheodoris

    2007-04-25

    In this paper we calculate the zero point energy density experienced by observers on M^4 due to a massless scalar field defined throughout M^4 x T^2_F, where T^2_F are fuzzy extra dimensions. Using the Green's function approach we calculate the energy density for the commutative torus and the fuzzy torus. We calculate then the energy density for the fuzzy torus using the Hamiltonian approach. Agreement is shown between Green's function and Hamiltonian approaches.

  16. Global Bifurcation Destroying The Experimental Torus T2

    E-Print Network [OSTI]

    T. Pereira; M. S. Baptista; M. B. Reyes; I. L. Caldas; J. C. Sartorelli; J. Kurths

    2007-06-22

    We show experimentally the scenario of a two-frequency torus $T^2$ breakdown, in which a global bifurcation occurs due to the collision of a torus with an unstable periodic orbit, creating a heteroclinic saddle connection, followed by an intermittent behavior.

  17. RADON TRANSFORM ON THE TORUS AHMED ABOUELAZ AND FRANOIS ROUVIRE

    E-Print Network [OSTI]

    Vallette, Bruno

    RADON TRANSFORM ON THE TORUS AHMED ABOUELAZ AND FRANÇOIS ROUVIÈRE Abstract. We consider the Radon-Ricci spaces etc. We consider here the n-dimensional (at) torus Tn = Rn=Zn and the Radon transform de will thus enter the picture, as in the case of Radon transforms on Zn already studied by the ...rst author

  18. Charge to the External Review Committee for the NSTX-U Arc Fault During the commissioning of NSTX-U for its first test plasma, an arc took place in its

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    -U for its first test plasma, an arc took place in its Ohmic heating circuit inflicting significant damageCharge to the External Review Committee for the NSTX-U Arc Fault During the commissioning of NSTX questions below. 1. Technical cause: Are the causes for the arc correctly identified and understood

  19. Arithmetic functions in torus and tree networks

    DOE Patents [OSTI]

    Bhanot, Gyan (Princeton, NJ); Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Vranas, Pavlos M. (Bedford Hills, NY)

    2007-12-25

    Methods and systems for performing arithmetic functions. In accordance with a first aspect of the invention, methods and apparatus are provided, working in conjunction of software algorithms and hardware implementation of class network routing, to achieve a very significant reduction in the time required for global arithmetic operation on the torus. Therefore, it leads to greater scalability of applications running on large parallel machines. The invention involves three steps in improving the efficiency and accuracy of global operations: (1) Ensuring, when necessary, that all the nodes do the global operation on the data in the same order and so obtain a unique answer, independent of roundoff error; (2) Using the topology of the torus to minimize the number of hops and the bidirectional capabilities of the network to reduce the number of time steps in the data transfer operation to an absolute minimum; and (3) Using class function routing to reduce latency in the data transfer. With the method of this invention, every single element is injected into the network only once and it will be stored and forwarded without any further software overhead. In accordance with a second aspect of the invention, methods and systems are provided to efficiently implement global arithmetic operations on a network that supports the global combining operations. The latency of doing such global operations are greatly reduced by using these methods.

  20. Magnetic surfaces in an axisymmetric torus

    SciTech Connect (OSTI)

    Skovoroda, A. A., E-mail: skovorod@nfi.kiae.ru [National Research Centre Kurchatov Institute (Russian Federation)

    2013-04-15

    A method is developed for specifying the boundary equilibrium magnetic surface in an axially symmetric torus by using the absolute values of the magnetic field B = B{sub s}({theta}) and the gradient of the poloidal flux vertical bar vertical bar {nabla}{Psi} vertical bar = vertical bar {nabla}{Psi} vertical bar {sub s}({theta}) in a special flux coordinate system. By setting two surface constants (e.g., the safety factor q and dp/d{Psi}) and matching the absolute values of the magnetic field and the flux gradient on a closed magnetic surface, it is possible to find all equilibrium magnetic functions (including n {center_dot} {nabla} ln B and the local shear s) and all constants (including the toroidal current J and the shear d{mu}/d{Psi}) on this surface. Such a non-traditional formulation of the boundary conditions in solving the stability problem in an axisymmetric torus allows one to impose intentional conditions on plasma confinement and MHD stability at the periphery of the system.

  1. Saturn in hot water: viscous evolution of the Enceladus torus

    E-Print Network [OSTI]

    Alison J. Farmer

    2008-06-09

    The detection of outgassing water vapor from Enceladus is one of the great breakthroughs of the Cassini mission. The fate of this water once ionized has been widely studied; here we investigate the effects of purely neutral-neutral interactions within the Enceladus torus. We find that, thanks in part to the polar nature of the water molecule, a cold (~180 K) neutral torus would undergo rapid viscous heating and spread to the extent of the observed hydroxyl cloud, before plasma effects become important. We investigate the physics behind the spreading of the torus, paying particular attention to the competition between heating and rotational line cooling. A steady-state torus model is constructed, and it is demonstrated that the torus will be observable in the millimeter band with the upcoming Herschel satellite. The relative strength of rotational lines could be used to distinguish between physical models for the neutral cloud.

  2. From Use Cases of the Joint European Torus towards Integrated Commissioning Requirements of the ITER Tokamak

    E-Print Network [OSTI]

    From Use Cases of the Joint European Torus towards Integrated Commissioning Requirements of the ITER Tokamak

  3. NSTX Weekly Report (September 10, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . On Sept 7 and 8, we began the Coaxial Helicity Injection (CHI) experiment, XP 1034 "Flux saving to Ohmic plasmas reaching 1MA of current with significant flux savings over purely inductive plasmas

  4. National Spherical Torus Experiment Upgrade Status and Plans*

    E-Print Network [OSTI]

    KAIST POSTECH Seoul Natl U ASIPP CIEMAT FOM Inst DIFFER ENEA, Frascati CEA, Cadarache IPP, Jülich IPP

  5. CONSTRUCTING THE NATIONAL Spherical Torus Experiment Upgrade took

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &BradburyMay 1, 2013, 4:15pmEnergyNovember 12, 2015,andLabDid

  6. Mechanical Design of the NSTX Liquid Lithium Divertor

    SciTech Connect (OSTI)

    R. Ellis, R. Kaita, H. Kugel, G. Paluzzi, M. Viola and R. Nygren

    2009-02-19

    The Liquid Lithium Divertor (LLD) on NSTX will be the first test of a fully-toroidal liquid lithium divertor in a high-power magnetic confinement device. It will replace part of the lower outboard divertor between a specified inside and outside radius, and ultimately provide a lithium surface exposed to the plasma with enough depth to absorb a significant particle flux. There are numerous technical challenges involved in the design. The lithium layer must be as thin as possible, and maintained at a temperature between 200 and 400 degrees Celsius to minimize lithium evaporation. This requirement leads to the use of a thick copper substrate, with a thin stainless steel layer bonded to the plasma-facing surface. A porous molybdenum layer is then plasma-sprayed onto the stainless steel, to provide a coating that facilitates full wetting of the surface by the liquid lithium. Other challenges include the design of a robust, vacuumcompatible heating and cooling system for the LLD. Replacement graphite tiles that provided the proper interface between the existing outer divertor and the LLD also had to be designed, as well as accommodation for special LLD diagnostics. This paper describes the mechanical design of the LLD, and presents analyses showing the performance limits of the LLD.

  7. Design and Operation of a Fast Electromagnetic Inductive Massive Gas Injection Valve for NSTX-Ua)

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Design and Operation of a Fast Electromagnetic Inductive Massive Gas Injection Valve for NSTX-Ua) R the operation of an electromagnetic valve, that does not incorporate ferromagnetic materials, are presented baratron gauge. The valve injects over 200 Torr.L of nitrogen in less than 3 ms, which remains unchanged

  8. Raman spectroscopy of carbon dust samples from NSTX Y. Raitses a,*, C.H. Skinner a

    E-Print Network [OSTI]

    Duffy, Thomas S.

    . The Raman measurements indicate that the production of carbon dust particles in NSTX involves modifications to be similar to those measured for carbon deposits from atmospheric pressure helium arc discharge responsible for dust production: (i) evap- oration and sublimation of thermally overloaded wall material

  9. Fast 2-D camera control, data acquisition, and database techniques for edge studies on NSTX

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Fast 2-D camera control, data acquisition, and database techniques for edge studies on NSTX W Nova Photonics, Princeton, NJ, 08543, USA Abstract Fast 2-D cameras examine a variety of important methods used to organize the fast camera data and to facilitate physics insights from it. An example

  10. Magnetic Diagnostics For Equilibrium Reconstruction And Realtime Plasma Control In NSTX-Upgrade

    SciTech Connect (OSTI)

    Gerhardt, Stefan P.; Erickson, Keith; Kaita, Robert; Lawson, John; Mozulay, Robert; Mueller, Dennis; Que, Weiguo; Rahman, Nabidur; Schneider, Hans; Smalley, Gustav; Tresemer, Kelsey

    2014-06-01

    This paper describes aspects of magnetic diagnostics for realtime control in NSTX-U. The sensor arrangement on the upgraded center column is described. New analog and digital circuitry for processing the plasma current rogowski data are presented. An improved algorithm for estimating the plasma vertical velocity for feedback control is presented.

  11. Macroscopic Stability Research on NSTXMacroscopic Stability Research on NSTX --UpdateUpdate

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    .) 4October 6th ­ 9th , 2009 Non-axisymmetric error field (n=1) can lock the plasma Well-known linear, K. Tritz6, and the NSTX Research Team 1Department of Applied Physics, Columbia University, New York, NY 2Plasma Physics Laboratory, Princeton University, Princeton, NJ 3University of Rochester

  12. Cascade of torus doubling bifurcations in a detuned laser

    SciTech Connect (OSTI)

    Krents, A A [S.P. Korolev Samara State Aerospace University, Samara (Russian Federation); Molevich, N E [Samara Branch of the P.N. Lebedev Physical Institute, Russian Academy of Sciences, Samara (Russian Federation)

    2009-08-31

    By using a simplified system of Maxwell-Bloch equations (with the adiabatically excluded polarisation of the medium), we studied the processes proceeding in the cross section of a light wave propagating in a wide-aperture laser emitting at the frequency detuned from the transition-line centre. It is shown that in the model under study the passage to the chaotic regime during a change in the wave propagation velocity across the aperture occurs via the doubling bifurcations of an ergodic two-dimensional torus. The spectrum of Lyapunov exponents is found and it is established that at bifurcation points a structurally unstable three-dimensional torus is produced, which gives rise to a stable doubled ergodic torus. (nonlinear optical phenomena)

  13. Maass Cusp Forms on Singly Punctured Two-Torus

    SciTech Connect (OSTI)

    Siddig, Abubaker Ahmed Mohamed [Laboratory of Computational Sciences and Informatics, Institute for Mathematical Research Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Shah, Nurisya Mohd [Theoretical Physics Group, Department of Physics, Faculty of Science Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Zainuddin, Hishamuddin [Laboratory of Computational Sciences and Informatics, Institute for Mathematical Research Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Theoretical Physics Group, Department of Physics, Faculty of Science Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)

    2009-07-07

    Quantum mechanical systems on punctured surfaces modeled by hyperbolic spaces can play an interesting role in exploring quantum chaos and in studying behaviour of future quantum nano-devices. The case of singly-punctured two-torus, for example, has been well-studied in the literature particularly for its scattering states. However, the bound states on the punctured torus given by Maass cusp forms are lesser known. In this note, we report on the algorithm of numerically computing these functions and we present ten lower-lying eigenvalues for each odd and even Maass cusp forms.

  14. Design and Construction of the NSTX Bakeout, Cooling and Vacuum Systems L. E. Dudek, W. Blanchard, M. Kalish, R. Gernhardt and R. F. Parsells

    E-Print Network [OSTI]

    Design and Construction of the NSTX Bakeout, Cooling and Vacuum Systems L. E. Dudek, W. Blanchard operation of the NSTX bakeout, water cooling and vacuum systems. The bakeout system is designed for two the external vessel is cooled to 150 °C. The second mode cools the first wall to 150 °C and the external vessel

  15. Prepared for the U.S. Department of Energy under Contract DE-AC02-76CH03073. Princeton Plasma Physics Laboratory

    E-Print Network [OSTI]

    (NSTX) D.A. Gates, R. Maingi, J. Menard, S. Kaye, S.A. Sabbagh, G. Taylor, J.R. Wilson, et al. November2 , G. Taylor1 , J.R. Wilson1 , M.G. Bell1 , R.E. Bell1 , S. Bernabei1 , J. Bialek2 , T. Biewer1 , W in the National Spherical Torus Experiment (NSTX) D. A. Gates1 , R. Maingi4 , J. Menard1 , S. Kaye1 , S.A. Sabbagh

  16. HHFW Power Flow Along Magnetic Field Lines In The Scrape-off Layer of NSTX

    SciTech Connect (OSTI)

    Rory Perkins, et. al.

    2012-02-27

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast wave heating and current drive.

  17. NSTX-U Advances in Real-time C++11 on Linux | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines lightGeospatialDevelopment of09 August 7,AdministrationAprilNSTX-U

  18. Ashtekar Formulation of 2+1 Gravity on a Torus

    E-Print Network [OSTI]

    N. Manojlovic; A. Mikovic

    1992-04-09

    Pure (2+1)-dimensional Einstein gravity is analysed in the Ashtekar formulation, when the spatial manifold is a torus. We have found a set of globally defined observables, forming a closed algebra. This allowed us to solve the quantum constraints, and to show that the reduced phase space of the Ashtekar formulation is greater then the corresponding space of the Witten formulation. Furthermore, we have found a globally defined time variable which satisfies all the requiriments of an extrinsic time variable in quantum gravity.

  19. Compact Torus Accelerator Driven Inertial Confinement Fusion Power Plant HYLIFE-CT

    SciTech Connect (OSTI)

    Logan, B G; Moir, R W; Tabak, M; Bieri, R L; Hammer, J H; Hartman, C W; Hoffman, M A; Leber, R L; Petzoldt, R W; Tobin, M T

    2005-03-30

    A Compact Torus Accelerator (CTA) is used to accelerate a Compact Torus (CT) to 35 MJ kinetic energy which is focused to a 20 mm diameter where its kinetic energy is converted to a shaped x-ray pulse of 30 MJ. The capsule yield with a prescribed radiation profile is calculated to be (gain 60 times 30 MJ) 1.8 GJ. Schemes for achieving this profile are described. The CT is accelerated in a length of 30 m within an annulus of 150 mm ID and 300 mm OD where the maximum magnetic field is 28 T. A 2.5 m conical taper reduces the mean diameter of the CT from 225 mm to 20 mm. The conical section is made out of solid Li{sub 2}BeF{sub 4}. The target with its frozen conical guide section is accurately placed at the end of the accelerator about once per second. The reactor called HYLIFE uses liquid jets to attenuate blast effects including shrapnel from the shattered conical guide section and radiation so that the vessel is expected to last 30 years. The calculated cost of electricity is estimated (in constant 1988 dollars) to be about 4.8 cents/kW {center_dot} h compared to the future cost of nuclear and coal of 4.3 to 5.8 cents/kW {center_dot} h. The CT driver contributes 17% to the cost of electricity. Present CT's make 2 x 10{sup 8} W/cm{sup 2}; the goal of experiments in progress is 10{sup 11} W/cm{sup 2} with further modifications to allow 10{sup 12}W/cm{sup 2}, whereas the reactor requires 10{sup 15} W/cm{sup 2} in a shaped pulse.

  20. High-resolution Tangential AXUV Arrays for Radiated Power Density Measurements on NSTX-U

    SciTech Connect (OSTI)

    Delgado-Aparicio, L; Bell, R E; Faust, I; Tritz, K; Diallo, A; Gerhardt, S P; Kozub, T A; LeBlanc, B P; Stratton, B C

    2014-07-01

    Precise measurements of the local radiated power density and total radiated power are a matter of the uttermost importance for understanding the onset of impurity-induced instabilities and the study of particle and heat transport. Accounting of power balance is also needed for the understanding the physics of various divertor con#12;gurations for present and future high-power fusion devices. Poloidal asymmetries in the impurity density can result from high Mach numbers and can impact the assessment of their flux-surface-average and hence vary the estimates of P[sub]rad (r, t) and (Z[sub]eff); the latter is used in the calculation of the neoclassical conductivity and the interpretation of non-inductive and inductive current fractions. To this end, the bolometric diagnostic in NSTX-U will be upgraded, enhancing the midplane coverage and radial resolution with two tangential views, and adding a new set of poloidally-viewing arrays to measure the 2D radiation distribution. These systems are designed to contribute to the near- and long-term highest priority research goals for NSTX-U which will integrate non-inductive operation at reduced collisionality, with high-pressure, long energy-confinement-times and a divertor solution with metal walls.

  1. Deuterium Beam Acceleration with 3rd Harmonic ICRH in Joint European Torus: Sawtooth Stabilization and Alfvén Eigenmodes

    E-Print Network [OSTI]

    Deuterium Beam Acceleration with 3rd Harmonic ICRH in Joint European Torus: Sawtooth Stabilization and Alfvén Eigenmodes

  2. Towards identifying the mechanisms underlying field-aligned edge-loss of HHFW power on NSTX

    SciTech Connect (OSTI)

    Perkins, R. J. [Princeton Plasma Physics Laboratory (PPPL); Ahn, Joonwook [ORNL; Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); Bertelli, Nicola [Princeton Plasma Physics Laboratory (PPPL); Diallo, A. [Princeton Plasma Physics Laboratory (PPPL); Gerhardt, S. [Princeton Plasma Physics Laboratory (PPPL); Gray, T. K. [Oak Ridge National Laboratory (ORNL); Green, David L [ORNL; Jaeger, E. F. [XCEL; Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Jaworski, M. A. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Kramer, G. [Princeton Plasma Physics Laboratory (PPPL); McLean, Adam G [ORNL; Maingi, Rajesh [ORNL; Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Podesta, M. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Sabbagh, S. A. [Columbia University; Scotti, F. [Princeton Plasma Physics Laboratory (PPPL); Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)

    2013-01-01

    Fast-wave heating will be a major heating scheme on ITER, as it can heat ions directly and is relatively unaffected by the large machine size unlike neutral beams. However, fast-wave interactions with the plasma edge can lead to deleterious effects such as, in the case of the high-harmonic fast-wave (HHFW) system on NSTX, large losses of fast-wave power in the scrape off layer (SOL) under certain conditions. In such scenarios, a large fraction of the lost HHFW power is deposited on the upper and lower divertors in bright spiral shapes. The responsible mechanism(s) has not yet been identified but may include fast-wave propagation in the scrape off layer, parametric decay instability, and RF currents driven by the antenna reactive fields. Understanding and mitigating these losses is important not only for improving the heating and current-drive on NSTX-Upgrade but also for understanding fast-wave propagation across the SOL in any fast-wave system. This talk summarizes experimental results demonstrating that the flow of lost HHFW power to the divertor regions largely follows the open SOL magnetic field lines. This lost power flux is relatively large close to both the antenna and the last closed flux surface with a reduced level in between, so the loss mechanism cannot be localized to the antenna. At the same time, significant losses also occur along field lines connected to the inboard edge of the bottom antenna plate. The power lost within the spirals is roughly estimated, showing that these field-aligned losses to the divertor are significant but may not account for the total HHFW loss. To elucidate the role of the onset layer for perpendicular fast-wave propagation with regards to fast-wave propagation in the SOL, a cylindrical cold-plasma model is being developed. This model, in addition to advanced RF codes such as TORIC and AORSA, is aimed at identifying the underlying mechanism(s) behind these SOL losses, to minimize their effects in NSTX-U, and to predict their importance in ITER.

  3. Towards identifying the mechanisms underlying field-aligned edge-loss of HHFW power on NSTX

    SciTech Connect (OSTI)

    Perkins, R. J.; Bell, R. E.; Bertelli, N.; Diallo, A.; Gerhardt, S.; Hosea, J. C.; Jaworski, M. A.; LeBlanc, B. P.; Kramer, G. J.; Maingi, R.; Phillips, C. K.; Podestà, M.; Roquemore, L.; Scotti, F.; Taylor, G.; Wilson, J. R.; Ahn, J-W.; Gray, T. K.; Green, D. L.; McLean, A.; and others

    2014-02-12

    Fast-wave heating will be a major heating scheme on ITER, as it can heat ions directly and is relatively unaffected by the large machine size unlike neutral beams. However, fast-wave interactions with the plasma edge can lead to deleterious effects such as, in the case of the high-harmonic fast-wave (HHFW) system on NSTX, large losses of fast-wave power in the scrape off layer (SOL) under certain conditions. In such scenarios, a large fraction of the lost HHFW power is deposited on the upper and lower divertors in bright spiral shapes. The responsible mechanism(s) has not yet been identified but may include fast-wave propagation in the scrape off layer, parametric decay instability, and RF currents driven by the antenna reactive fields. Understanding and mitigating these losses is important not only for improving the heating and current-drive on NSTX-Upgrade but also for understanding fast-wave propagation across the SOL in any fast-wave system. This talk summarizes experimental results demonstrating that the flow of lost HHFW power to the divertor regions largely follows the open SOL magnetic field lines. This lost power flux is relatively large close to both the antenna and the last closed flux surface with a reduced level in between, so the loss mechanism cannot be localized to the antenna. At the same time, significant losses also occur along field lines connected to the inboard edge of the bottom antenna plate. The power lost within the spirals is roughly estimated, showing that these field-aligned losses to the divertor are significant but may not account for the total HHFW loss. To elucidate the role of the onset layer for perpendicular fast-wave propagation with regards to fast-wave propagation in the SOL, a cylindrical cold-plasma model is being developed. This model, in addition to advanced RF codes such as TORIC and AORSA, is aimed at identifying the underlying mechanism(s) behind these SOL losses, to minimize their effects in NSTX-U, and to predict their importance in ITER.

  4. Low energy ion distribution measurements in Madison Symmetric Torus plasmas

    SciTech Connect (OSTI)

    Titus, J. B., E-mail: jtitus@cepast.famu.edu; Mezonlin, E. D. [Florida A and M University, Tallahassee, Florida 32310 (United States); Johnson, J. A. [Pyramid Plasmas LLC, Lawrenceville, Georgia 30043 (United States)

    2014-06-15

    Charge-exchange neutrals contain information about the contents of a plasma and can be detected as they escape confinement. The Florida A and M University compact neutral particle analyzer (CNPA), used to measure the contents of neutral particle flux, has been reconfigured, calibrated, and installed on the Madison Symmetric Torus (MST) for high temperature deuterium plasmas. The energy range of the CNPA has been extended to cover 0.34–5.2?keV through an upgrade of the 25 detection channels. The CNPA has been used on all types of MST plasmas at a rate of 20?kHz throughout the entire discharge (?70?ms). Plasma parameter scans show that the ion distribution is most dependent on the plasma current. Magnetic reconnection events throughout these scans produce stronger poloidal electric fields, stronger global magnetic modes, and larger changes in magnetic energy all of which heavily influence the non-Maxwellian part of the ion distribution (the fast ion tail)

  5. Effect of Deuterium Gas Puff On The Edge Plasma In NSTX

    SciTech Connect (OSTI)

    Zweben, S. J.

    2014-02-20

    This paper describes a detailed examination of the effects of a relatively small pulsed deuterium gas puff on the edge plasma and edge turbulence in NSTX. This gas puff caused little or no change in the line-averaged plasma density or total stored energy, or in the edge density and electron temperature up to the time of the peak of the gas puff. The radial profile of the D? light emission and the edge turbulence within this gas puff did not vary significantly over its rise and fall, implying that these gas puffs did not significantly perturb the local edge plasma or edge turbulence. These measurements are compared with modeling by DEGAS 2, UEDGE, and with simplified estimates for the expected effects of this gas puff.

  6. Observation of Non-Maxwellian Electron Distributions in th e NSTX Divertor

    SciTech Connect (OSTI)

    M.A. Jaworski, et. al.

    2013-03-07

    The scrape-off layer plasma at the tokamak region is characterized by open field lines and often contains large variations in plasma properties along these field-lines. Proper characterization of local plasma conditions is critical to assessing plasma-material interaction processes occuring at the target. Langmuir probes are frequently employed in tokamak divertors but are challenging to interpretation. A kinetic interpretation for Langmuir probes in NSTX has yielded non-Maxwellian electron distributions in the divertor characterized by cool bulk populations and energetic tail populations with temperatures of 2-4 times the bulk. Spectroscopic analysis and modeling confirms the bulk plasma temperature and density which can only be obtained with the kinetic interpretation

  7. Axisymmetric, High-, Steady-State Plasma Torus: A "Wind Tunnel" to Develop Whole Device Models

    E-Print Network [OSTI]

    Mauel, Michael E.

    on Integrated Simulations for Magnetic Fusion Energy Sciences: Community Teleconference Presentation CD modes; no density limits; ...) · Axisymmetry (simplicity; omnigenous drifts;...) · Simple kinetics Fusion-Relevant Plasma Torus: Axisymmetric, Levitated Current Ring Fusion Relevant Physics: Particle

  8. Numerical simulation of torus breakdown to chaos in an atmospheric-pressure dielectric barrier discharge

    SciTech Connect (OSTI)

    Zhang, J.; Wang, Y. H.; Wang, D. Z. [Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-08-15

    Understanding the routes to chaos occurring in atmospheric-pressure dielectric barrier discharge systems by changing controlling parameters is very important to predict and control the dynamical behaviors. In this paper, a route of a quasiperiodic torus to chaos via the strange nonchaotic attractor is observed in an atmospheric-pressure dielectric barrier discharge driven by triangle-wave voltage. By increasing the driving frequency, the discharge system first bifurcates to a quasiperiodic torus from a stable single periodic state, and then torus and phase-locking periodic state appear and disappear alternately. In the meantime, the torus becomes increasingly wrinkling and stretching, and gradually approaches a fractal structure with the nonpositive largest Lyapunov exponent, i.e., a strange nonchaotic attractor. After that, the discharge system enters into chaotic state. If the driving frequency is further increased, another well known route of period-doubling bifurcation to chaos is also observed.

  9. 10D Massive Type IIA Supergravities as the uplift of Parabolic M2-brane Torus bundles

    E-Print Network [OSTI]

    del Moral, Maria Pikar Garcia

    2015-01-01

    We remark that the two 10D massive deformations of the $N=2$ maximal type IIA supergravity (Romans and HLW supergravity) are associated to the low energy limit of the uplift to 10D of M2-brane torus bundles with parabolic monodromy linearly and non-linearly realized respectively. Romans supergravity corresponds to M2-brane compactified on a twice-punctured torus bundle.

  10. 10D Massive Type IIA Supergravities as the uplift of Parabolic M2-brane Torus bundles

    E-Print Network [OSTI]

    Maria Pikar Garcia del Moral; Alvaro Restuccia

    2015-11-15

    We remark that the two 10D massive deformations of the $N=2$ maximal type IIA supergravity (Romans and HLW supergravity) are associated to the low energy limit of the uplift to 10D of M2-brane torus bundles with parabolic monodromy linearly and non-linearly realized respectively. Romans supergravity corresponds to M2-brane compactified on a twice-punctured torus bundle.

  11. THE CLASSIFICATION OF DEHN FILLINGS ON THE OUTER TORUS OF A 1-BRIDGE BRAID

    E-Print Network [OSTI]

    Wu, Ying-Qing

    THE CLASSIFICATION OF DEHN FILLINGS ON THE OUTER TORUS OF A 1-BRIDGE BRAID EXTERIOR WHICH PRODUCE SOLID TORI Ying-Qing Wu1 Abstract. Let K = K(w, b, t) be a 1-bridge braid in a solid torus V , and let for such Dehn fillings. 1. Introduction A knot K in a 3-manifold M is a 0-bridge knot if it is isotopic

  12. Magnetohydrodynamic modes analysis and control of Fusion Advanced Studies Torus high-current scenarios

    SciTech Connect (OSTI)

    Villone, F.; Mastrostefano, S. [Euratom-ENEA-CREATE Ass., DIEI, Univ. di Cassino e Lazio Merid., Cassino (Italy); Calabrò, G.; Vlad, G.; Crisanti, F.; Fusco, V. [C. R. Frascati, Euratom-ENEA Ass., Via E. Fermi 45, 00044 Frascati (Italy); Marchiori, G.; Bolzonella, T.; Marrelli, L.; Martin, P. [Cons. RFX, Euratom-ENEA-RFX Ass., Corso Stati Uniti 4, 35127 Padova (Italy); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Mantica, P. [IFP-CNR, Euratom-ENEA-CNR Ass. Via Cozzi 53, 20125 Milano (Italy)

    2014-08-15

    One of the main FAST (Fusion Advanced Studies Torus) goals is to have a flexible experiment capable to test tools and scenarios for safe and reliable tokamak operation, in order to support ITER and help the final DEMO design. In particular, in this paper, we focus on operation close to a possible border of stability related to low-q operation. To this purpose, a new FAST scenario has then been designed at I{sub p}?=?10 MA, B{sub T}?=?8.5?T, q{sub 95}???2.3. Transport simulations, carried out by using the code JETTO and the first principle transport model GLF23, indicate that, under these conditions, FAST could achieve an equivalent Q???3.5. FAST will be equipped with a set of internal active coils for feedback control, which will produce magnetic perturbation with toroidal number n?=?1 or n?=?2. Magnetohydrodynamic (MHD) mode analysis and feedback control simulations performed with the codes MARS, MARS-F, CarMa (both assuming the presence of a perfect conductive wall and using the exact 3D resistive wall structure) show the possibility of the FAST conductive structures to stabilize n?=?1 ideal modes. This leaves therefore room for active mitigation of the resistive mode (down to a characteristic time of 1?ms) for safety purposes, i.e., to avoid dangerous MHD-driven plasma disruption, when working close to the machine limits and magnetic and kinetic energy density not far from reactor values.

  13. 5/28/08 6:03 PMPrinceton University -PPPL to phase out compact stellarator experiment, upgrade spherical torus program Page 1 of 2http://www.princeton.edu/main/news/archive/S21/15/04A97/index.xml?section=topstories

    E-Print Network [OSTI]

    for and determining the attractiveness of the compact stellarator as the basis for a fusion power reactor. However and current-drive techniques. This may result in smaller, more powerful fusion reactors. In a statement5/28/08 6:03 PMPrinceton University - PPPL to phase out compact stellarator experiment, upgrade

  14. Ideal magnetohydrodynamic equilibrium in a non-symmetric topological torus

    SciTech Connect (OSTI)

    Weitzner, Harold

    2014-02-15

    An alternative representation of an ideal magnetohydrodynamic equilibrium is developed. The representation is a variation of one given by A. Salat, Phys. Plasmas 2, 1652 (1995). The system of equations is used to study the possibility of non-symmetric equilibria in a topological torus, here an approximate rectangular parallelopiped, with periodicity in two of the three rectangular coordinates. An expansion is carried out in the deviation of pressure surfaces from planes. Resonances are manifest in the process. Nonetheless, provided the magnetic shear is small, it is shown that it is possible to select the magnetic fields and flux surfaces in such a manner that no singularities appear on resonant surfaces. One boundary surface of the parallelopiped is not arbitrary but is dependent on the equilibrium in question. A comparison of the solution sets of axisymmetric and non-axisymmetric equilibria suggests that the latter have a wider class of possible boundary shapes but more restrictive rotational transform profiles. No proof of convergence of the series is given.

  15. An In-situ materials analysis particle probe (MAPP) diagnostic to study particle density control and hydrogenic fuel retention in NSTX

    SciTech Connect (OSTI)

    Allain, Jean-Paul

    2014-09-05

    A new materials analysis particle probe (MAPP) was designed, constructed and tested to develop understanding of particle control and hydrogenic fuel retention in lithium-based plasma-facing surfaces in NSTX. The novel feature of MAPP is an in-situ tool to probe the divertor NSTX floor during LLD and lithium-coating shots with subsequent transport to a post-exposure in-vacuo surface analysis chamber to measure D retention. In addition, the implications of a lithiated graphite-dominated plasma-surface environment in NSTX on LLD performance, operation and ultimately hydrogenic pumping and particle control capability are investigated in this proposal. MAPP will be an invaluable tool for erosion/redeposition simulation code validation.

  16. NSTX presentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines lightGeospatialDevelopment of09 August 7,AdministrationApril

  17. FPA Meeting, 10/11-12/05 Status of World ST Research Status of World Spherical Torus Research

    E-Print Network [OSTI]

    and Energy Policy October 11-12, 2005, Washington, DC Supported by Office of Science College W&M Colorado Sch Has a Tradition of Strong Collaboration · Active bilateral exchanges ­ UK-US on NSTX and MAST ­ START options for economical fusion reactor Phase III Target Strategy of the All-Japan ST Research Program (Prof

  18. Fourier Modeling of the Radio Torus Surrounding Supernova 1987A

    E-Print Network [OSTI]

    C. -Y. Ng; B. M. Gaensler; L. Staveley-Smith; R. N. Manchester; M. J. Kesteven; L. Ball; A. K. Tzioumis

    2008-05-27

    We present detailed Fourier modeling of the radio remnant of Supernova 1987A, using high-resolution 9 GHz and 18 GHz data taken with the Australia Telescope Compact Array over the period 1992 to 2008. We develop a parameterized three-dimensional torus model for the expanding radio shell, in which the emission is confined to an inclined equatorial belt; our model also incorporates both a correction for light travel-time effects and an overall east-west gradient in the radio emissivity. By deriving an analytic expression for the two-dimensional Fourier transform of the projected three-dimensional brightness distribution, we can fit our spatial model directly to the interferometric visibility data. This provides robust estimates to the radio morphology at each epoch. The best-fit results suggest a constant remnant expansion at 4000 +/- 400 km/s over the 16-year period covered by the observations. The model fits also indicate substantial mid-latitude emission, extending to 40 degree on either side of the equatorial plane. This likely corresponds to the extra-planar structure seen in H$\\alpha$ and Ly$\\alpha$ emission from the supernova reverse shock, and broadly supports hydrodynamic models in which the complex circumstellar environment was produced by a progression of interacting winds from the progenitor. Our model quantifies the clear asymmetry seen in the radio images: we find that the eastern half of the radio remnant is consistently ~40 brighter than the western half at all epochs, which may result from an asymmetry in the ejecta distribution between these two hemispheres.

  19. High-Harmonic Fast-Wave Power Flow Along Magnetic Field Lines in the Scrape-Off Layer of NSTX

    SciTech Connect (OSTI)

    Perkins, R. J. [Princeton Plasma Physics Laboratory (PPPL); Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Kramer, G. [Princeton Plasma Physics Laboratory (PPPL); Ahn, Joonwook [ORNL; Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); Diallo, A. [Princeton Plasma Physics Laboratory (PPPL); Gerhardt, S. [Princeton Plasma Physics Laboratory (PPPL); Gray, T. K. [Oak Ridge National Laboratory (ORNL); Green, David L [ORNL; Jaeger, Erwin Frederick [ORNL; Jaworski, M. A. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); McLean, Adam G [ORNL; Maingi, Rajesh [ORNL; Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Roquemore, L. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Sabbagh, S. A. [Columbia University; Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)

    2012-01-01

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast-wave heating and current drive.

  20. High-resolution tangential absolute extreme ultraviolet arrays for radiated power density measurements on NSTX-U

    SciTech Connect (OSTI)

    Delgado-Aparicio, L.; Bell, R. E.; Diallo, A.; Gerhardt, S. P.; Kozub, T. A.; LeBlanc, B. P.; Stratton, B. C. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Faust, I. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Tritz, K. [The Johns Hopkins University, Baltimore, Maryland 21209 (United States)

    2014-11-15

    The radiated-power-density diagnostic on the equatorial midplane for the NSTX-U tokamak will be upgraded to measure the radial structure of the photon emissivity profile with an improved radial resolution. This diagnostic will enhance the characterization and studies of power balance, impurity transport, and MHD. The layout and response expected of the new system is shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation from high-Z impurities is also addressed.

  1. Fast Ion Loss Diagnostic Plans for NSTX D. S. Darrow, R. Bell, D. W. Johnson, H. Kugel, and J. R. Wilson,

    E-Print Network [OSTI]

    Fast Ion Loss Diagnostic Plans for NSTX D. S. Darrow, R. Bell, D. W. Johnson, H. Kugel, and J. R. There may, in addition, be losses of fast ions arising from high harmonic fast wave (HHFW) heating. Most probe will be employed. The probe will measure loss of fast ions with E>1 keV at three radial locations

  2. Observations of Improved Stability and Confinement in a High-Self-Organized Spherical-Torus-Like Field-Reversed Configuration

    E-Print Network [OSTI]

    Washington at Seattle, University of

    -Torus-Like Field-Reversed Configuration H. Y. Guo, A. L. Hoffman, L. C. Steinhauer, and K. E. Miller Redmond Plasma (FRC) with a spherical- torus- (ST-)like core is produced in the translation, confinement. This plasma state exhibits a remarkable stabilizing property for the ubiquitous n 2 centrifugally driven

  3. FMEA on the superconducting torus for the Jefferson Lab 12 GeV accelerator upgrade

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ghoshal, Probir K.; Biallas, George H.; Fair, Ruben J.; Rajput-Ghoshal, Renuka; Schneider, William J.; Legg, Robert A.; Kashy, David H.; Hogan, John P.; Wiseman, Mark A.; Luongo, Cesar; et al

    2015-01-16

    As part of the Jefferson Lab 12GeV accelerator upgrade project, Hall B requires two conduction cooled superconducting magnets. One is a magnet system consisting of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration and the second is an actively shielded solenoidal magnet system consisting of 5 coils. Both magnets are to be wound with Superconducting Super Collider-36 NbTi strand Rutherford cable soldered into a copper channel. This paper describes the various failure modes in torus magnet along with the failure modes that could be experienced by the torus and its interaction with the solenoid which is located inmore »close proximity.« less

  4. Understanding ion cyclotron harmonic fast wave heating losses in the scrape off layer of tokamak plasmas

    SciTech Connect (OSTI)

    Bertelli, N [PPPL; Jaeger, E F; Hosea, J C; Phillips, C K; Berry, L; Bonoli, P T; Gerhardt, S P [PPPL; Green, D; LeBlanc, B [PPPL; Perkins, R J; Ryan, P M; Taylor, G; Valeo, E J; Wilso, J R; Wright, J C

    2014-07-01

    Fast waves at harmonics of the ion cyclotron frequency, which have been used successfully on National Spherical Torus Experiment (NSTX), will also play an important role in ITER and are a promising candidate for the Fusion Nuclear Science Facility (FNSF) designs based on spherical torus (ST). Experimental studies of high harmonic fast waves (HHFW) heating on the NSTX have demonstrated that substantial HHFW power loss occurs along the open field lines in the scrape-off layer (SOL), but the mechanism behind the loss is not yet understood. The full wave RF code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain, is applied to specific NSTX discharges in order to predict the effects and possible causes of this power loss. In the studies discussed here, a collisional damping parameter has been implemented in AORSA as a proxy to represent the real, and most likely nonlinear, damping processes. A prediction for the NSTX Upgrade (NSTX-U) experiment, that will begin operation next year, is also presented, indicating a favorable condition for the experiment due to a wider evanescent region in edge density.*Research supported by the U.S. DOE under Contract No. DE-AC02-09CH11466 with Princeton University.

  5. Predictions of VRF on a Langmuir Probe under the RF Heating Spiral on the Divertor Floor on NSTX-U

    SciTech Connect (OSTI)

    Hosea, J C [PPPL; Perkins, R J [PPPL; Jaworski, M A [PPPL; Kramer, G J [PPPL; Ahn, J-W [ORNL

    2014-07-01

    RF heating deposition spirals are observed on the divertor plates on NSTX as shown in for a NB plus RF heating case. It has been shown that the RF spiral is tracked quite well by the spiral mapping of the strike points on the divertor plate of magnetic field lines passing in front of the high harmonic fast wave (HHFW) antenna on NSTX. Indeed, both current instrumented tiles and Langmuir probes respond to the spiral when it is positioned over them. In particular, a positive increment in tile current (collection of electrons) is obtained when the spiral is over the tile. This current can be due to RF rectification and/or RF heating of the scrape off layer (SOL) plasma along the magnetic field lines passing in front of the the HHFW antenna. It is important to determine quantitatively the relative contributions of these processes. Here we explore the properties of the characteristics of probes on the lower divertor plate to determine the likelyhood that the primary cause of the RF heat deposition is RF rectification.

  6. NSTX S.A.Sabbagh IEA Workshop 59 02/15/05 S. A. Sabbagh1, A.C. Sontag1, R. E. Bell2, J. Bialek1, A. Garofalo1, D.A. Gates2,

    E-Print Network [OSTI]

    NSTX S.A.Sabbagh ­ IEA Workshop 59 ­ 02/15/05 S. A. Sabbagh1, A.C. Sontag1, R. E. Bell2, J. Bialek1 IPP, Garching U Quebec IEA Workshop 59: Shape and Aspect Ratio Optimization for High Beta, Steady of Sciences, Hefei, China #12;NSTX S.A.Sabbagh ­ IEA Workshop 59 ­ 02/15/05 Physics study of global MHD mode

  7. Physics basis for a spherical torus power plant S.C. Jardin a,

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    Physics basis for a spherical torus power plant S.C. Jardin a, *, C.E. Kessel a , J. Menard a , T for a fusion power plant. A special class of wall-stabilized high-b high-bootstrap fraction low-aspect-ratio tokamak; Fusion power plant; Plasma operating regime 1. Introduction The most significant difference

  8. Axisymmetric, High-, Steady-State Plasma Torus: A "Wind-Tunnel" to Develop Whole Device Models

    E-Print Network [OSTI]

    Mauel, Michael E.

    Axisymmetric, High-, Steady-State Plasma Torus: A "Wind-Tunnel" to Develop Whole Device Models Mike College, Hanover, NH White Paper for the 2015 DOE Integrated Simulations Workshop (Topics: C, D) Motivation The development of experimentally-validated whole device models is a grand challenge of fusion

  9. 558: Calculation of Eddy Currents in the ETE Spherical Torus G.O. Ludwig

    E-Print Network [OSTI]

    558: Calculation of Eddy Currents in the ETE Spherical Torus G.O. Ludwig Instituto Nacional de model based on the Green's function method. The distribution of eddy currents is calculated using a thin well with values of the eddy currents measured in ETE. INTRODUCTION This paper presents a magnetostatic

  10. An Inexpensive Ohmic Transformer Firing Circuit for the CDXU Spherical Torus

    E-Print Network [OSTI]

    1 An Inexpensive Ohmic Transformer Firing Circuit for the CDX­U Spherical Torus T. Munsat, R designed and modeled a simple, efficient circuit for delivering power to the CDX­U ohmic transformer, spherical tori) have traditionally driven plasma current by using the transformer action of a centrally

  11. An Inexpensive Ohmic Transformer Firing Circuit for the CDX-U Spherical Torus

    E-Print Network [OSTI]

    1 An Inexpensive Ohmic Transformer Firing Circuit for the CDX-U Spherical Torus T. Munsat, R designed and modeled a simple, efficient circuit for delivering power to the CDX-U ohmic transformer, spherical tori) have traditionally driven plasma current by using the transformer action of a centrally

  12. Thermoelectric Rotating Torus for Fusion A. B. Hassam and Yi-Min Huang

    E-Print Network [OSTI]

    Hassam, Adil

    Thermoelectric Rotating Torus for Fusion A. B. Hassam and Yi-Min Huang Institute for Plasma power maintains the rotation and also heats the plasma. The thermoelectric effect from the resultingRevLett.91.195002 PACS numbers: 52.58.­c, 52.30.­q, 52.55.­s In magnetized plasma, thermoelectric currents

  13. Scaling of linear microtearing stability for a high collisionality National Spherical Torus Experiment discharge

    E-Print Network [OSTI]

    Hammett, Greg

    of Physics. Related Articles Hybrid-like 2/1 flux-pumping and magnetic island evolution due to edge localized in the presence of suffi- cient E Â B shear,1­4 which occurs in strongly beam heated plasmas. However

  14. Fusion alpha-particle diagnostics for DT experiments on the joint European torus

    SciTech Connect (OSTI)

    Kiptily, V. G.; Beaumont, P.; Syme, D. B. [Euratom / CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon (United Kingdom); Belli, F. [Associazione Euratom -ENEA sulla Fusione, C.R. Frascati, C.P. 65, Frascati (Italy); Cecil, F. E.; Riva, M. [Colorado School of Mines, Golden, CO (United States); Conroy, S.; Ericsson, G. [Department of Physics and Astronomy, Uppsala University, BOX 516, Uppsala (Sweden); Craciunescu, T. [Association Euratom -MEdC, National Institute for Laser, Plasma and Radiation Physics (Romania); Garcia-Munoz, M. [Max-Planck-Institut für Plasmaphysik, EURATOM-Association IPP, Garching, D-85748 (Germany); Curuia, M.; Soare, S. [Association Euratom -MEdC, National Institute for Cryogenics and Isotopic Technology (Romania); Darrow, D. [Princeton Plasma Physics Lab, Princeton, NJ (United States); Fernandes, A. M.; Pereira, R. C.; Sousa, J. [Euratom/IST Fusion Association, Centro de Fusão Nuclear, 1049-001 Lisboa (Portugal); Giacomelli, L.; Voitsekhovitch, I. [CNISM, Dipartimento di Fisica, Universita Milano-Bicocca, Milano (Italy); Gorini,; Nocente, M. [CNISM, Dipartimento di Fisica, Universita Milano-Bicocca, Milano, Italy and Associazione Euratom -ENEA sulla Fusione, IFP Milano (Italy); and others

    2014-08-21

    JET equipped with ITER-like wall (a beryllium wall and a tungsten divertor) can provide auxiliary heating with power up to 35MW, producing a significant population of ?-particles in DT operation. The direct measurements of alphas are very difficult and ?-particle studies require a significant development of dedicated diagnostics. JET now has an excellent set of confined and lost fast particle diagnostics for measuring the ?-particle source and its evolution in space and time, ?-particle energy distribution, and ?-particle losses. This paper describes how the above mentioned JET diagnostic systems could be used for ?-particle measurements, and what options exist for keeping the essential ?-particle diagnostics functioning well in the presence of intense DT neutron flux. Also, ?-particle diagnostics for ITER are discussed.

  15. FORMATION OF A COMPACT TORUS USING A TOROIDAL PLASMA GUN

    E-Print Network [OSTI]

    Levine, Morton A.

    2013-01-01

    USING A TOROIDAL PLASMA GUN Morton A. Levine and Philip A.bounce back toward the gun. If this experiment is successfulUSING A TOROIDAL PLASMA GUN Morton A. Levine and Philip A.

  16. A Star on Earth

    ScienceCinema (OSTI)

    Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

    2014-06-06

    At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

  17. A Star on Earth

    SciTech Connect (OSTI)

    Prager, Stewart; Zwicker, Andrew; Hammet, Greg; Tresemer, Kelsey; Diallo, Ahmed

    2014-03-05

    At the Energy Department's Princeton Plasma Physics Lab, scientists are trying to accomplish what was once considered the realm of science fiction: create a star on Earth. The National Spherical Torus Experiment (NSTX) is a magnetic fusion device that is used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which, under the right conditions, nuclear fusion will occur. Fusion is the energy source of the sun and all of the stars. Not just limited to theoretical work, the NSTX is enabling cutting-edge research to develop fusion as a future energy source.

  18. Reduced model prediction of electron temperature profiles in...

    Office of Scientific and Technical Information (OSTI)

    FUSION TECHNOLOGY Confinement; H-mode Plasma Confinement; Spherical Torus; Spherical Tokamak; Stability, Microinstability; Tokamaks, NSTX; Transport Phenomena Word Cloud More...

  19. Lagrange multiplier and Wess-Zumino variable as large extra dimensions in the torus universe

    E-Print Network [OSTI]

    Nejad, Salman Abarghouei; Monemzadeh, Majid

    2015-01-01

    We study the effect of the topology of universe by gauging the non-relativistic particle model on the torus and 3-torus, using the symplectic formalism of constrained systems and embedding those models on extended phase-spaces. Also, we obtain the generators of the gauge transformations for gauged models. Extracting the corresponding Poisson structure of the existed constraints, we show the effect of the topology on the canonical structure of the phase-spaces of those models and suggest some phenomenology to prove the topology of the universe and probable non-commutative structure of the space. In addition, we show that the number of large extra dimensions in the Phase-spaces of the gauged embeded models are exactly two. Moreover, in the classical form, we talk over MOND theory in order to study the origin of the terms appeared in the gauged theory, which modify the Newton's second law.

  20. Condensates and instanton - torus knot duality. Hidden Physics at UV scale

    E-Print Network [OSTI]

    A. Gorsky; A. Milekhin

    2014-12-29

    We establish the duality between the torus knot superpolynomials or the Poincare polynomials of the Khovanov homology and particular condensates in Omega-deformed 5D supersymmetric QED compactified on a circle with 5d Chern-Simons(CS) term. This is the generalization of the Witten's recipe of the evaluation of the knot polynomials via Wilson loops in 3d CS theory for case of the torus knots. It is explicitly shown that $n$-instanton contribution to the condensate of the massless flavor in the background of four-observable, which can be associated with some composite defect, exactly coincides with the superpolynomial of the T(n,nk+1) torus knot where k - is the level of CS term. In contrast to the previously known results, the particular torus knot corresponds not to the partition function of the gauge theory but to the particular instanton contribution and summation over the knots has to be performed in order to obtain the complete answer. The instantons are sitting almost at the top of each other and the physics of the "fat point" where the UV degrees of freedom are slaved with point-like instantons turns out to be quite rich. Also also see knot polynomials in the quantum mechanics on the instanton moduli space. We consider the different limits of this correspondence focusing at their physical interpretation and compare the algebraic structures at the both sides of the correspondence. Using the AGT correspondence, we establish a connection between superpolynomials for unknots and q-deformed DOZZ factors which suggests the interpretation of the composite defect.

  1. Tomographic analysis of neutron and gamma pulse shape distributions from liquid scintillation detectors at Joint European Torus

    SciTech Connect (OSTI)

    Giacomelli, L.; Department of Physics, Università degli Studi di Milano-Bicocca, Milano ; Conroy, S.; Department of Physics and Astronomy, Uppsala University, Uppsala ; Gorini, G.; Horton, L.; Murari, A.; Popovichev, S.; Syme, D. B.

    2014-02-15

    The Joint European Torus (JET, Culham, UK) is the largest tokamak in the world devoted to nuclear fusion experiments of magnetic confined Deuterium (D)/Deuterium-Tritium (DT) plasmas. Neutrons produced in these plasmas are measured using various types of neutron detectors and spectrometers. Two of these instruments on JET make use of organic liquid scintillator detectors. The neutron emission profile monitor implements 19 liquid scintillation counters to detect the 2.45 MeV neutron emission from D plasmas. A new compact neutron spectrometer is operational at JET since 2010 to measure the neutron energy spectra from both D and DT plasmas. Liquid scintillation detectors are sensitive to both neutron and gamma radiation but give light responses of different decay time such that pulse shape discrimination techniques can be applied to identify the neutron contribution of interest from the data. The most common technique consists of integrating the radiation pulse shapes within different ranges of their rising and/or trailing edges. In this article, a step forward in this type of analysis is presented. The method applies a tomographic analysis of the 3-dimensional neutron and gamma pulse shape and pulse height distribution data obtained from liquid scintillation detectors such that n/? discrimination can be improved to lower energies and additional information can be gained on neutron contributions to the gamma events and vice versa.

  2. Two intervals R\\'enyi entanglement entropy of compact free boson on torus

    E-Print Network [OSTI]

    Liu, Feihu

    2015-01-01

    We compute the $N=2$ R\\'enyi entanglement entropy of two intervals at equal time in a circle, for the theory of a 2d compact complex free scalar at finite temperature. This is carried out by performing functional integral on a genus 3 ramified cover of the torus, wherein the quantum part of the integral is captured by the four point function of twist fields on the worldsheet torus, and the classical piece is given by summing over winding modes of the genus 3 surface onto the target space torus. The final result is given in terms of a product of theta function and certain multi-dimensional theta function. We demonstrate the T-duality invariance of the result. We also study its low temperature limit. In the case in which the size of the intervals and of their separation are much smaller than the whole system, our result is in exact agreement with the known result for two intervals on an infinite system at zero temperature \\cite{eeoftwo}. In the case in which the separation between the two intervals is much smal...

  3. Fast Ion Stabilization of the Ion Temperature Gradient Driven Modes in the Joint European Torus Hybrid-Scenario Plasmas: A Trigger Mechanism for Internal Transport Barrier Formation

    E-Print Network [OSTI]

    Fast Ion Stabilization of the Ion Temperature Gradient Driven Modes in the Joint European Torus Hybrid-Scenario Plasmas: A Trigger Mechanism for Internal Transport Barrier Formation

  4. A New Sawtooth Control Mechanism Relying on Toroidally Propagating Ion Cyclotron Resonance Frequency Waves: Theory and Joint European Torus Tokamak Experimental Evidence

    E-Print Network [OSTI]

    A New Sawtooth Control Mechanism Relying on Toroidally Propagating Ion Cyclotron Resonance Frequency Waves: Theory and Joint European Torus Tokamak Experimental Evidence

  5. Electromagnetic Transport From Microtearing Mode Turbulence

    SciTech Connect (OSTI)

    Guttenfelder, W; Kaye, S M; Nevins, W M; Wang, E; Bell, R E; Hammett, G W; LeBlanc, B P; Mikkelsen, D R

    2011-03-23

    This Letter presents non-linear gyrokinetic simulations of microtearing mode turbulence. The simulations include collisional and electromagnetic effects and use experimental parameters from a high beta discharge in the National Spherical Torus Experiment (NSTX). The predicted electron thermal transport is comparable to that given by experimental analysis, and it is dominated by the electromagnetic contribution of electrons free streaming along the resulting stochastic magnetic field line trajectories. Experimental values of flow shear can significantly reduce the predicted transport.

  6. Torus Formation in Neutron Star Mergers and Well-Localized Short Gamma-Ray Bursts

    E-Print Network [OSTI]

    R. Oechslin; H. -Th. Janka

    2006-02-22

    Merging neutron stars (NSs) are hot candidates for the still enigmatic sources of short gamma-ray bursts (GRBs). If the central engines of the huge energy release are accreting relic black holes (BHs) of such mergers, it is important to understand how the properties of the BH-torus systems, in particular disc masses and mass and rotation rate of the compact remnant, are linked to the characterizing parameters of the NS binaries. For this purpose we present relativistic smoothed particle hydrodynamics simulations with conformally flat approximation of the Einstein field equations and a physical, non-zero temperature equation of state. Thick disc formation is highlighted as a dynamical process caused by angular momentum transfer through tidal torques during the merging process of asymmetric systems or in the rapidly spinning triaxial post-merger object. Our simulations support the possibility that the first well-localized short and hard GRBs 050509b, 050709, 050724, 050813 have originated from NS merger events and are powered by neutrino-antineutrino annihilation around a relic BH-torus system. Using model parameters based on this assumption, we show that the measured GRB energies and durations lead to estimates for the accreted masses and BH mass accretion rates which are compatible with theoretical expectations. In particular, the low energy output and short duration of GRB 050509b set a very strict upper limit of less than 100 ms for the time interval after the merging until the merger remnant has collapsed to a BH, leaving an accretion torus with a small mass of only about 0.01 solar masses. This favors a (nearly) symmetric NS+NS binary with a typical mass as progenitor system.

  7. VOLUME54, NUMBER9 PHYSICAL REVIEW LETTERS 4 MARCH1985 Conversion of Wave Energy to Magnetic Field Energy in a Plasma Torus

    E-Print Network [OSTI]

    Karney, Charles

    VOLUME54, NUMBER9 PHYSICAL REVIEW LETTERS 4 MARCH1985 Conversion of Wave Energy to Magnetic Field Energy in a Plasma Torus N. J. Fisch and C. F. F. Karney Plasma Physics Laboratory, Princeton University on the Princeton Large Torus (PLT)' have converted wave energy to poloidal field energy with the remarkable

  8. VOLUME54, NUMBER9 PHYSICAL REVIEW LETTERS 4 MARCH1985 Conversion of Wave Energy to Magnetic Field Energy in a Plasma Torus

    E-Print Network [OSTI]

    Karney, Charles

    VOLUME54, NUMBER9 PHYSICAL REVIEW LETTERS 4 MARCH1985 Conversion of Wave Energy to Magnetic Field on the Princeton Large Torus (PLT)' have converted wave energy to poloidal field energy with the remarkable Energy in a Plasma Torus N. J. Fisch and C. F. F. Karney Plasma Physics Laboratory, Princeton University

  9. Conformal perturbation theory and higher spin entanglement entropy on the torus

    E-Print Network [OSTI]

    Shouvik Datta; Justin R. David; S. Prem Kumar

    2015-04-10

    We study the free fermion theory in 1+1 dimensions deformed by chemical potentials for holomorphic, conserved currents at finite temperature and on a spatial circle. For a spin-three chemical potential \\mu, the deformation is related at high temperatures to a higher spin black hole in hs[0] theory on AdS_3 spacetime. We calculate the order \\mu^2 corrections to the single interval Renyi and entanglement entropies on the torus using the bosonized formulation. A consistent result, satisfying all checks, emerges upon carefully accounting for both perturbative and winding mode contributions in the bosonized language. The order \\mu^2 corrections involve integrals that are finite but potentially sensitive to contact term singularities. We propose and apply a prescription for defining such integrals which matches the Hamiltonian picture and passes several non-trivial checks for both thermal corrections and the Renyi entropies at this order. The thermal corrections are given by a weight six quasi-modular form, whilst the Renyi entropies are controlled by quasi-elliptic functions of the interval length with modular weight six. We also point out the well known connection between the perturbative expansion of the partition function in powers of the spin-three chemical potential and the Gross-Taylor genus expansion of large-N Yang-Mills theory on the torus. We note the absence of winding mode contributions in this connection, which suggests qualitatively different entanglement entropies for the two systems.

  10. TORUS: Theory of Reactions for Unstable iSotopes - Year 1 Continuation and Progress Report

    SciTech Connect (OSTI)

    Arbanas, G; Elster, C; Escher, J; Mukhamedzhanov, A; Nunes, F; Thompson, I J

    2011-02-24

    The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding started on June 1, 2010, it will have been running for nine months by the date of submission of this Annual Continuation and Progress Report on March 1, 2011. The extent of funding was reduced from the original application, and now supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.

  11. Microtearing Instabilities and Electron Transport in the NSTX Spherical Tokamak K. L. Wong, S. Kaye, D. R. Mikkelsen, J. A. Krommes, K. Hill, R. Bell, and B. LeBlanc

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Microtearing Instabilities and Electron Transport in the NSTX Spherical Tokamak K. L. Wong, S. Kaye wave- length fluctuations and local electron heat diffusivity has been observed in the Tokamak Fusion Test Reactor (TFTR) tokamak [2], a mechanism based on broken magnetic surfaces proposed three decades

  12. Divertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    magnetic flux expansion and partial detachment of the outer strike point at several D2 injection rates of acceptable divertor plate material erosion rates and heat fluxes to q 10 MW/m2 , a limit imposedDivertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus

  13. Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization via periodic orbits

    E-Print Network [OSTI]

    Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization for the periodic orbits in a strongly coupled multidimen- sional Hamiltonian system, namely the hydrogen atom.15.Gy, 05.45.-a, 45.20.Jj I. INTRODUCTION The hydrogen atom in crossed electric and magnetic fields

  14. arXiv:astro-ph/010224014Feb2001 A dusty torus around the luminous young star LkH 101

    E-Print Network [OSTI]

    Tuthill, Peter

    , thermonuclear fusion begins. The remaining disk, which can still contain up to 0.3 times the mass of the star[3arXiv:astro-ph/010224014Feb2001 A dusty torus around the luminous young star LkH 101 Peter G. A star forms when a cloud of dust and gas collapses. It is generally believed that this collapse first

  15. Reverberation measurements of the inner radius of the dust torus in 17 Seyfert galaxies

    SciTech Connect (OSTI)

    Koshida, Shintaro [Center of Astro Engineering and Department of Electrical Engineering, Pontificia Univercsidad Catolica de Chile, Av. Vicuna Mackenna 4868 (Chile); Minezaki, Takeo; Yoshii, Yuzuru; Sakata, Yu; Sugawara, Shota [Institute of Astronomy, School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Kobayashi, Yukiyasu; Suganuma, Masahiro [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Enya, Keigo [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Tomita, Hiroyuki; Aoki, Tsutomu [Kiso Observatory, Institute of Astronomy, School of Science, University of Tokyo, 10762-30 Mitake, Kiso, Nagano 397-0101 (Japan); Peterson, Bruce A., E-mail: skoshida@ing.puc.cl, E-mail: minezaki@ioa.s.u-tokyo.ac.jp [Mount Stromlo Observatory, Research School of Astronomy and Astrophysics, Australian National University, Weston Creek P.O., ACT 2611 (Australia)

    2014-06-20

    We present the results of a dust reverberation survey for 17 nearby Seyfert 1 galaxies, which provides the largest homogeneous data collection for the radius of the innermost dust torus. A delayed response of the K-band light curve after the V-band light curve was found for all targets, and 49 measurements of lag times between the flux variation of the dust emission in the K band and that of the optical continuum emission in the V band were obtained by the cross-correlation function analysis and also by an alternative method for estimating the maximum likelihood lag. The lag times strongly correlated with the optical luminosity in the luminosity range of M{sub V} = –16 to –22 mag, and the regression analysis was performed to obtain the correlation log ?t (days) = –2.11 – 0.2 M{sub V} assuming ?t?L {sup 0.5}, which was theoretically expected. We discuss the possible origins of the intrinsic scatter of the dust lag-luminosity correlation, which was estimated to be approximately 0.13 dex, and we find that the difference of internal extinction and delayed response of changes in lag times to the flux variations could have partly contributed to intrinsic scatter. However, we could not detect any systematic change of the correlation with the subclass of the Seyfert type or the Eddington ratio. Finally, we compare the dust reverberation radius with the near-infrared interferometric radius of the dust torus and the reverberation radius of broad Balmer emission lines. The interferometric radius in the K band was found to be systematically larger than the dust reverberation radius in the same band by the about a factor of two, which could be interpreted by the difference between the flux-weighted radius and response-weighted radius of the innermost dust torus. The reverberation radius of the broad Balmer emission lines was found to be systematically smaller than the dust reverberation radius by about a factor of four to five, which strongly supports the unified scheme of the Seyfert type of active galactic nuclei (AGNs). Moreover, we examined the radius-luminosity correlations for the hard X-ray (14-195 keV) and the [O IV] ?25.89 ?m emission-line luminosities, which would be applicable for obscured AGNs.

  16. Central Safety Factor and #12;ßN Control on NSTX-U via Beam Power and Plasma Boundary Shape Modification, using TRANSP for Closed Loop Simulations

    SciTech Connect (OSTI)

    Boyer, M. D. [PPPL; Andre, R. [PPPL; Gates, David A. [PPPL; Gerhardt, S. [PPPL; Goumiri, I. R. [Princeton University; Menard, Jon [PPPL

    2014-08-01

    The high-performance operational goals of NSTX-U will require development of advanced feedback control algorithms, including control of ßN and the safety factor profile. In this work, a novel approach to simultaneously controlling #12;ßN and the value of the safety factor on the magnetic axis, q0, through manipulation of the plasma boundary shape and total beam power, is proposed. Simulations of the proposed scheme show promising results and motivate future experimental implementation and eventual integration into a more complex current profile control scheme planned to include actuation of individual beam powers, density, and loop voltage. As part of this work, a flexible framework for closed loop simulations within the high-fidelity code TRANSP was developed. The framework, used here to identify control-design-oriented models and to tune and test the proposed controller, exploits many of the predictive capabilities of TRANSP and provides a means for performing control calculations based on user-supplied data (controller matrices, target waveforms, etc.). The flexible framework should enable high-fidelity testing of a variety of control algorithms, thereby reducing the amount of expensive experimental time needed to implement new control algorithms on NSTX-U and other devices.

  17. Fast-wave Power Flow Along SOL Field Lines In NSTX nd The Associated Power Deposition Profile Across The SOL In Front Of The Antenna

    SciTech Connect (OSTI)

    Perkins, Roy

    2013-06-21

    Fast-wave heating and current drive efficiencies can be reduced by a number of processes in the vicinity of the antenna and in the scrape off layer (SOL). On NSTX from around 25% to more than 60% of the high-harmonic fast-wave power can be lost to the SOL regions, and a large part of this lost power flows along SOL magnetic field lines and is deposited in bright spirals on the divertor floor and ceiling. We show that field-line mapping matches the location of heat deposition on the lower divertor, albeit with a portion of the heat outside of the predictions. The field-line mapping can then be used to partially reconstruct the profile of lost fast-wave power at the midplane in front of the antenna, and the losses peak close to the last closed flux surface (LCFS) as well as the antenna. This profile suggests a radial standing-wave pattern formed by fast-wave propagation in the SOL, and this hypothesis will be tested on NSTX-U. Advanced RF codes must reproduce these results so that such codes can be used to understand this edge loss and to minimize RF heat deposition and erosion in the divertor region on ITER.

  18. Spectral asymmetry of the massless Dirac operator on a 3-torus

    SciTech Connect (OSTI)

    Downes, Robert J., E-mail: R.Downes@ucl.ac.uk; Vassiliev, Dmitri, E-mail: D.Vassiliev@ucl.ac.uk [Department of Mathematics, University College London, Gower Street, London WC1E 6BT (United Kingdom)] [Department of Mathematics, University College London, Gower Street, London WC1E 6BT (United Kingdom); Levitin, Michael, E-mail: M.Levitin@reading.ac.uk [Department of Mathematics and Statistics, University of Reading, Whiteknights, PO Box 220, Reading RG6 6AX (United Kingdom)] [Department of Mathematics and Statistics, University of Reading, Whiteknights, PO Box 220, Reading RG6 6AX (United Kingdom)

    2013-11-15

    Consider the massless Dirac operator on a 3-torus equipped with Euclidean metric and standard spin structure. It is known that the eigenvalues can be calculated explicitly: the spectrum is symmetric about zero and zero itself is a double eigenvalue. The aim of the paper is to develop a perturbation theory for the eigenvalue with smallest modulus with respect to perturbations of the metric. Here the application of perturbation techniques is hindered by the fact that eigenvalues of the massless Dirac operator have even multiplicity, which is a consequence of this operator commuting with the antilinear operator of charge conjugation (a peculiar feature of dimension 3). We derive an asymptotic formula for the eigenvalue with smallest modulus for arbitrary perturbations of the metric and present two particular families of Riemannian metrics for which the eigenvalue with smallest modulus can be evaluated explicitly. We also establish a relation between our asymptotic formula and the eta invariant.

  19. High-frequency propagation for the Schroedinger equation on the torus

    E-Print Network [OSTI]

    Fabricio Macia

    2009-10-07

    The main objective of this paper is understanding the propagation laws obeyed by high-frequency limits of Wigner distributions associated to solutions to the Schroedinger equation on the standard d-dimensional torus T^{d}. From the point of view of semiclassical analysis, our setting corresponds to performing the semiclassical limit at times of order 1/h, as the characteristic wave-length h of the initial data tends to zero. It turns out that, in spite that for fixed h every Wigner distribution satisfies a Liouville equation, their limits are no longer uniquely determined by those of the Wigner distributions of the initial data. We characterize them in terms of a new object, the resonant Wigner distribution, which describes high-frequency effects associated to the fraction of the energy of the sequence of initial data that concentrates around the set of resonant frequencies in phase-space T^{*}T^{d}. This construction is related to that of the so-called two-microlocal semiclassical measures. We prove that any limit \\mu of the Wigner distributions corresponding to solutions to the Schroedinger equation on the torus is completely determined by the limits of both the Wigner distribution and the resonant Wigner distribution of the initial data; moreover, \\mu follows a propagation law described by a family of density-matrix Schroedinger equations on the periodic geodesics of T^{d}. Finally, we present some connections with the study of the dispersive behavior of the Schroedinger flow (in particular, with Strichartz estimates). Among these, we show that the limits of sequences of position densities of solutions to the Schroedinger equation on T^2 are absolutely continuous with respect to the Lebesgue measure.

  20. FY11 NSTX RUN LOG FY 11 Run started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    experiment XP-1041 Week's End 87.83 2.20 10/18/10 6.79 94.62 2.37 33 32 Flux saving and improved coupling to OH XP-1034 10/19/10 7.62 102.24 2.56 42 39 Flux saving and improved coupling to OH XP-1034 10/20/10 6.5 108.74 2.72 32 31 MSE Diagnostic Calibration XMP-33 Flux saving and improved coupling to OH XP-1034 10

  1. From the Boltzmann equation to the incompressible Navier-Stokes equations on the torus: a quantitative error estimate

    E-Print Network [OSTI]

    Marc Briant

    2015-07-11

    We investigate the Boltzmann equation, depending on the Knudsen number, in the Navier-Stokes perturbative setting on the torus. Using hypocoercivity, we derive a new proof of existence and exponential decay for solutions close to a global equilibrium, with explicit regularity bounds and rates of convergence. These results are uniform in the Knudsen number and thus allow us to obtain a strong derivation of the incompressible Navier-Stokes equations as the Knudsen number tends to $0$. Moreover, our method is also used to deal with other kinetic models. Finally, we show that the study of the hydrodynamical limit is rather different on the torus than the one already proved in the whole space as it requires averaging in time, unless the initial layer conditions are satisfied.

  2. Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization via periodic orbits

    E-Print Network [OSTI]

    Stephan Gekle; Jörg Main; Thomas Bartsch; T. Uzer

    2006-10-02

    A hierarchical ordering is demonstrated for the periodic orbits in a strongly coupled multidimensional Hamiltonian system, namely the hydrogen atom in crossed electric and magnetic fields. It mirrors the hierarchy of broken resonant tori and thereby allows one to characterize the periodic orbits by a set of winding numbers. With this knowledge, we construct the action variables as functions of the frequency ratios and carry out a semiclassical torus quantization. The semiclassical energy levels thus obtained agree well with exact quantum calculations.

  3. Observational evidence of torus instability as trigger mechanism for coronal mass ejections: The 2011 August 4 filament eruption

    SciTech Connect (OSTI)

    Zuccarello, F. P.; Poedts, S.; Seaton, D. B.; Mierla, M.; Rachmeler, L. A.; Romano, P.; Zuccarello, F. E-mail: Stefaan.Poedts@wis.kuleuven.be E-mail: marilena@oma.be E-mail: Paolo.Romano@oact.inaf.it

    2014-04-20

    Solar filaments are magnetic structures often observed in the solar atmosphere and consist of plasma that is cooler and denser than their surroundings. They are visible for days—even weeks—which suggests that they are often in equilibrium with their environment before disappearing or erupting. Several eruption models have been proposed that aim to reveal what mechanism causes (or triggers) these solar eruptions. Validating these models through observations represents a fundamental step in our understanding of solar eruptions. We present an analysis of the observation of a filament eruption that agrees with the torus instability model. This model predicts that a magnetic flux rope embedded in an ambient field undergoes an eruption when the axis of the flux rope reaches a critical height that depends on the topology of the ambient field. We use the two vantage points of the Solar Dynamics Observatory (SDO) and the Solar TErrestrial RElations Observatory to reconstruct the three-dimensional shape of the filament, to follow its morphological evolution, and to determine its height just before eruption. The magnetograms acquired by SDO/Helioseismic and Magnetic Imager are used to infer the topology of the ambient field and to derive the critical height for the onset of the torus instability. Our analysis shows that the torus instability is the trigger of the eruption. We also find that some pre-eruptive processes, such as magnetic reconnection during the observed flares and flux cancellation at the neutral line, facilitated the eruption by bringing the filament to a region where the magnetic field was more vulnerable to the torus instability.

  4. An axisymmetric hydrodynamical model for the torus wind in AGN. II: X-ray excited funnel flow

    E-Print Network [OSTI]

    Dorodnitsyn, A; Proga, D

    2008-01-01

    We have calculated a series of models of outflows from the obscuring torus in active galactic nuclei (AGN). Our modeling assumes that the inner face of a rotationally supported torus is illuminated and heated by the intense X-rays from the inner accretion disk and black hole. As a result of such heating a strong biconical outflow is observed in our simulations. We calculate 3-dimensional hydrodynamical models, assuming axial symmetry, and including the effects of X-ray heating, ionization, and radiation pressure. We discuss the behavior of a large family of these models, their velocity fields, mass fluxes and temperature, as functions of the torus properties and X-ray flux. Synthetic warm absorber spectra are calculated, assuming pure absorption, for sample models at various inclination angles and observing times. We show that these models have mass fluxes and flow speeds which are comparable to those which have been inferred from observations of Seyfert 1 warm absorbers, and that they can produce rich absorp...

  5. An axisymmetric hydrodynamical model for the torus wind in AGN. II: X-ray excited funnel flow

    E-Print Network [OSTI]

    A. Dorodnitsyn; T. Kallman; D. Proga

    2008-06-23

    We have calculated a series of models of outflows from the obscuring torus in active galactic nuclei (AGN). Our modeling assumes that the inner face of a rotationally supported torus is illuminated and heated by the intense X-rays from the inner accretion disk and black hole. As a result of such heating a strong biconical outflow is observed in our simulations. We calculate 3-dimensional hydrodynamical models, assuming axial symmetry, and including the effects of X-ray heating, ionization, and radiation pressure. We discuss the behavior of a large family of these models, their velocity fields, mass fluxes and temperature, as functions of the torus properties and X-ray flux. Synthetic warm absorber spectra are calculated, assuming pure absorption, for sample models at various inclination angles and observing times. We show that these models have mass fluxes and flow speeds which are comparable to those which have been inferred from observations of Seyfert 1 warm absorbers, and that they can produce rich absorption line spectra.

  6. ACCRETION AND OUTFLOW FROM A MAGNETIZED, NEUTRINO COOLED TORUS AROUND THE GAMMA-RAY BURST CENTRAL ENGINE

    SciTech Connect (OSTI)

    Janiuk, Agnieszka; Mioduszewski, Patryk [Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Moscibrodzka, Monika, E-mail: agnes@cft.edu.pl [Department of Physics, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, NV 89154 (United States)

    2013-10-20

    We calculate the structure and short-term evolution of a gamma-ray burst (GRB) central engine in the form of a turbulent torus accreting onto a stellar mass black hole. Our models apply to the short GRB events, in which a remnant torus forms after the neutron star-black hole or a double neutron star merger and is subsequently accreted. We study the two-dimensional, relativistic models and concentrate on the effects of the black hole and flow parameters as well as the neutrino cooling. We compare the resulting structure and neutrino emission to the results of our previous one-dimensional simulations. We find that the neutrino cooled torus launches a powerful mass outflow, which contributes to the total neutrino luminosity and mass loss from the system. The neutrino luminosity may exceed the Blandford-Znajek luminosity of the polar jets and the subsequent annihilation of neutrino-antineutrino pairs will provide an additional source of power to the GRB emission.

  7. Demonstration of Tokamak Ohmic Flux Saving by Transient Coaxial Helicity Injection in the National Spherical Torus Experiment

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Demonstration of Tokamak Ohmic Flux Saving by Transient Coaxial Helicity Injection in the National in a significant Ohmic flux saving and produced equivalent quality tokamak plasmas. In addition, for the first time

  8. Simulation of non-resonant internal kink mode with toroidal rotation in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Wang, Feng; Liu, J. Y. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Fu, G. Y.; Breslau, J. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Tritz, Kevin [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218 (United States)] [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2013-07-15

    Plasmas in spherical and conventional tokamaks, with weakly reversed shear q profile and minimum q above but close to unity, are susceptible to an non-resonant (m,n) = (1,1) internal kink mode. This mode can saturate and persist and can induce a (2,1) seed island for Neoclassical Tearing Mode. [Breslau et al. Nucl. Fusion 51, 063027 (2011)]. The mode can also lead to large energetic particle transport and significant broadening of beam-driven current. Motivated by these important effects, we have carried out extensive nonlinear simulations of the mode with finite toroidal rotation using parameters and profiles of an NTSX plasma with a weakly reversed shear profile. The numerical results show that, at the experimental level, plasma rotation has little effect on either equilibrium or linear stability. However, rotation can significantly influence the nonlinear dynamics of the (1,1) mode and the induced (2,1) magnetic island. The simulation results show that a rotating helical equilibrium is formed and maintained in the nonlinear phase at finite plasma rotation. In contrast, for non-rotating cases, the nonlinear evolution exhibits dynamic oscillations between a quasi-2D state and a helical state. Furthermore, the effects of rotation are found to greatly suppress the (2,1) magnetic island even at a low level.

  9. Embedding global barrier and collective in torus network with each node combining input from receivers according to class map for output to senders

    DOE Patents [OSTI]

    Chen, Dong; Coteus, Paul W; Eisley, Noel A; Gara, Alan; Heidelberger, Philip; Senger, Robert M; Salapura, Valentina; Steinmacher-Burow, Burkhard; Sugawara, Yutaka; Takken, Todd E

    2013-08-27

    Embodiments of the invention provide a method, system and computer program product for embedding a global barrier and global interrupt network in a parallel computer system organized as a torus network. The computer system includes a multitude of nodes. In one embodiment, the method comprises taking inputs from a set of receivers of the nodes, dividing the inputs from the receivers into a plurality of classes, combining the inputs of each of the classes to obtain a result, and sending said result to a set of senders of the nodes. Embodiments of the invention provide a method, system and computer program product for embedding a collective network in a parallel computer system organized as a torus network. In one embodiment, the method comprises adding to a torus network a central collective logic to route messages among at least a group of nodes in a tree structure.

  10. Description NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    0.00 B 1030 Award Inner (TF) Conductor Material Contract 0 12JAN11A 12JAN11A 100 0.00 B 1035 Award Inner (TF) Conductor Machining contract 0 14SEP11A 14SEP11A 100 0.00 B 1037 Award TF Lead Extensions 0 30AUG11A 30AUG11A 100 0.00 B 1038 Award Friction Stir Weld Contract 0 30AUG11A 30AUG11A 100 0.00 B FY

  11. VOLUME 81, NUMBER 15 P H Y S I C A L R E V I E W L E T T E R S 12 OCTOBER 1998 Band Distributions for Quantum Chaos on a Torus

    E-Print Network [OSTI]

    Wilkinson, Michael

    for Quantum Chaos on a Torus Itzhack Dana,1 Mario Feingold,2 and Michael Wilkinson3 1 Department of Physics in the field of quantum chaos, can be reduced to a torus, either in configuration space (e.g., the Sinai in the quantum-chaos literature [4­12], although attention has often been confined to strict periodicity. General

  12. Electromagnetic and Mechanical Analysis of the Coil Structure for the CLAS12 Torus for 12 GeV Upgrade

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ghoshal, P. K.; Pastor, O.; Kashy, D.; Schneider, W.; Wiseman, M.; Zarecky, M.; Young, G.; Rode, C.; Elouadrhiri, L.; Burkert, V.

    2014-12-18

    The torus magnet for the CLAS12 spectrometer is a 3.6 T superconducting magnet being designed and built as part of the Jefferson Lab 12 GeV Upgrade. The magnet consists of six coil case assemblies mounted to a cold central hub. The coil case assembly consists of an aluminum case and cover enclosing an epoxy vacuum impregnated coil pack. The coil pack consists of a 117 turn double-pancake winding wrapped with 2 layers of 0.635 mm thick copper cooling sheets. The coil case assembly is cooled by supercritical helium at 4.6 K. This report details the structural analysis of the coilmore »case assembly and the assessment of the coil pack stresses. For the normal operation of the torus magnet, the coil case assembly was analyzed for cool down to 4.6 K and the Lorentz forces at normal operating current. In addition to the normal operating configuration, the coil case assembly was analyzed for Lorentz forces arising from coil misalignment and current imbalances. The allowable stress criteria for the magnet followed the approach of the ASME codes. Primary stresses were limited to the lesser of 2/3 times the yield strength or 1/3 times the ultimate tensile strength. Primary plus secondary stresses were limited to 3 times the primary stress allowable. The analysis was performed using ANSYS Maxwell to calculate the magneto-static loads and ANSYS Mechanical to calculate the stresses.« less

  13. Electromagnetic and Mechanical Analysis of the Coil Structure for the CLAS12 Torus for 12 GeV Upgrade

    SciTech Connect (OSTI)

    Ghoshal, P. K.; Pastor, O.; Kashy, D.; Schneider, W.; Wiseman, M.; Zarecky, M.; Young, G.; Rode, C.; Elouadrhiri, L.; Burkert, V.

    2014-12-18

    The torus magnet for the CLAS12 spectrometer is a 3.6 T superconducting magnet being designed and built as part of the Jefferson Lab 12 GeV Upgrade. The magnet consists of six coil case assemblies mounted to a cold central hub. The coil case assembly consists of an aluminum case and cover enclosing an epoxy vacuum impregnated coil pack. The coil pack consists of a 117 turn double-pancake winding wrapped with 2 layers of 0.635 mm thick copper cooling sheets. The coil case assembly is cooled by supercritical helium at 4.6 K. This report details the structural analysis of the coil case assembly and the assessment of the coil pack stresses. For the normal operation of the torus magnet, the coil case assembly was analyzed for cool down to 4.6 K and the Lorentz forces at normal operating current. In addition to the normal operating configuration, the coil case assembly was analyzed for Lorentz forces arising from coil misalignment and current imbalances. The allowable stress criteria for the magnet followed the approach of the ASME codes. Primary stresses were limited to the lesser of 2/3 times the yield strength or 1/3 times the ultimate tensile strength. Primary plus secondary stresses were limited to 3 times the primary stress allowable. The analysis was performed using ANSYS Maxwell to calculate the magneto-static loads and ANSYS Mechanical to calculate the stresses.

  14. The spatial Lambda-Fleming-Viot process on a large torus: genealogies in the presence of recombination

    E-Print Network [OSTI]

    Etheridge, A M

    2011-01-01

    We extend the spatial Lambda-Fleming-Viot process introduced in [BEV10] to incorporate recombination. The process models allele frequencies in a population which is distributed over the two-dimensional torus T(L) of sidelength L and is subject to two kinds of reproduction events : small events of radius O(1) and much rarer large events of radius O(L^{alpha}) for some alpha in (0,1]. We investigate the correlation between the times to the most recent common ancestor of alleles at two linked loci for a sample of size two from the population. These individuals are initially sampled from `far apart' on the torus. As L tends to infinity, depending on the frequency of the large events, the recombination rate and the initial distance between the two individuals sampled, we obtain either a complete decorrelation of the coalescence times at the two loci, or a sharp transition between a first period of complete correlation and a subsequent period during which the remaining times needed to reach the most recent common a...

  15. Accurate evolutions of unequal-mass neutron-star binaries: properties of the torus and short GRB engines

    E-Print Network [OSTI]

    Luciano Rezzolla; Luca Baiotti; Bruno Giacomazzo; David Link; Jose A. Font

    2010-05-13

    We present new results from accurate and fully general-relativistic simulations of the coalescence of unmagnetized binary neutron stars with various mass ratios. The evolution of the stars is followed through the inspiral phase, the merger and prompt collapse to a black hole, up until the appearance of a thick accretion disk, which is studied as it enters and remains in a regime of quasi-steady accretion. Although a simple ideal-fluid equation of state with \\Gamma=2 is used, this work presents a systematic study within a fully general relativistic framework of the properties of the resulting black-hole--torus system produced by the merger of unequal-mass binaries. More specifically, we show that: (1) The mass of the torus increases considerably with the mass asymmetry and equal-mass binaries do not produce significant tori if they have a total baryonic mass M_tot >~ 3.7 M_sun; (2) Tori with masses M_tor ~ 0.2 M_sun are measured for binaries with M_tot ~ 3.4 M_sun and mass ratios q ~ 0.75-0.85; (3) The mass of the torus can be estimated by the simple expression M_tor(q, M_tot) = [c_1 (1-q) + c_2](M_max-M_tot), involving the maximum mass for the binaries and coefficients constrained from the simulations, and suggesting that the tori can have masses as large as M_tor ~ 0.35 M_sun for M_tot ~ 2.8 M_sun and q ~ 0.75-0.85; (4) Using a novel technique to analyze the evolution of the tori we find no evidence for the onset of non-axisymmetric instabilities and that very little, if any, of their mass is unbound; (5) Finally, for all the binaries considered we compute the complete gravitational waveforms and the recoils imparted to the black holes, discussing the prospects of detection of these sources for a number of present and future detectors.

  16. Global oscillations of a fluid torus as a modulation mechanism for black-hole high-frequency QPOs

    E-Print Network [OSTI]

    Michal Bursa

    2005-10-15

    We study strong-gravity effects on modulation of radiation emerging from accreting compact objects as a possible mechanism for flux modulation in QPOs. We construct a toy model of an oscillating torus in the slender approximation assuming thermal bremsstrahlung for the intrinsic emissivity of the medium and we compute observed (predicted) radiation signal including contribution of indirect (higher-order) images and caustics in the Schwarzschild spacetime. We show that the simplest oscillation mode in an accretion flow, axisymmetric up-and-down motion at the meridional epicyclic frequency, may be directly observable when it occurs in the inner parts of accretion flow around black holes. Together with the second oscillation mode, an in-and-out motion at the radial epicyclic frequency, it may then be responsible for the high-frequency modulations of the X-ray flux observed at two distinct frequencies (twin HF-QPOs) in micro-quasars.

  17. Suppression of energetic particle driven instabilities with HHFW heating

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Fredrickson, E. D.; Taylor, G.; Bertelli, N.; Darrow, D. S.; Gorelenkov, N.; Kramer, G.; Liu, D.; Crocker, N. A.; Kubota, S.; White, R.

    2015-01-01

    In plasmas in the National Spherical Torus Experiment (NSTX) [Ono et al., Nucl. Fusion 40 (2000) 557] heated with neutral beams, the beam ions typically excite Energetic Particle Modes (EPMs or fishbones), and Toroidal, Global or Compressional Alfvén Eigenmodes (TAE, GAE, CAE). These modes can redistribute the energetic beam ions, altering the beam driven current profile and the plasma heating profile, or they may affect electron thermal transport or cause losses of the beam ions. In this paper we present experimental results where these instabilities, driven by the super-thermal beam ions, are suppressed with the application of High Harmonic Fastmore »Wave heating.« less

  18. Anomalous Electron Transport Due to Multiple High Frequency Beam Ion Driven Alfven Eigenmode

    SciTech Connect (OSTI)

    Gorelenkov, N. N.; Stutman, D.; Tritz, K.; Boozer, A.; Delgardo-Aparicio, L.; Fredrickson, E.; Kaye, S.; White, R.

    2010-07-13

    We report on the simulations of recently observed correlations of the core electron transport with the sub-thermal ion cyclotron frequency instabilities in low aspect ratio plasmas of the National Spherical Torus Experiment (NSTX). In order to model the electron transport of the guiding center code ORBIT is employed. A spectrum of test functions of multiple core localized Global shear Alfven Eigenmode (GAE) instabilities based on a previously developed theory and experimental observations is used to examine the electron transport properties. The simulations exhibit thermal electron transport induced by electron drift orbit stochasticity in the presence of multiple core localized GAE.

  19. Suppression of energetic particle driven instabilities with HHFW heating

    SciTech Connect (OSTI)

    Fredrickson, E. D.; Taylor, G.; Bertelli, N.; Darrow, D. S.; Gorelenkov, N.; Kramer, G.; Liu, D.; Crocker, N. A.; Kubota, S.; White, R.

    2015-01-01

    In plasmas in the National Spherical Torus Experiment (NSTX) [Ono et al., Nucl. Fusion 40 (2000) 557] heated with neutral beams, the beam ions typically excite Energetic Particle Modes (EPMs or fishbones), and Toroidal, Global or Compressional Alfvén Eigenmodes (TAE, GAE, CAE). These modes can redistribute the energetic beam ions, altering the beam driven current profile and the plasma heating profile, or they may affect electron thermal transport or cause losses of the beam ions. In this paper we present experimental results where these instabilities, driven by the super-thermal beam ions, are suppressed with the application of High Harmonic Fast Wave heating.

  20. Variable Reddening and Broad Absorption Lines in the Narrow-line Seyfert 1 Galaxy WPVS 007: an Origin in the Torus

    E-Print Network [OSTI]

    Leighly, Karen M; Grupe, Dirk; Terndrup, Donald M; Komossa, S

    2015-01-01

    We report the discovery of an occultation event in the low-luminosity narrow-line Seyfert 1 galaxy WPVS 007 in 2015 February and March. In concert with longer timescale variability, these observations place strong constraints on the nature and location of the absorbing material. Swift monitoring has revealed a secular decrease since ~2010 accompanied by flattening of the optical and UV photometry that suggests variable reddening. Analysis of four Hubble Space Telescope COS observations since 2010, including a Director's Discretionary time observation during the occultation, shows that the broad-absorption-line velocity offset and the CIV emission-line width both decrease as the reddening increases. The occultation dynamical timescale, the BAL variability dynamical timescale, and the density of the BAL gas show that both the reddening material and the broad-absorption-line gas are consistent with an origin in the torus. These observations can be explained by a scenario in which the torus is clumpy with variabl...

  1. Gyrokinetic Theory and Simulation of Experiments

    E-Print Network [OSTI]

    . Development of & physics in gyrokinetic equations 3. Development of nonlinear 5-D simulations of gyrokinetic in the solar wind: Theory, simulations and comparisons with observations", VI2.2 , Thursday 3:30 PM · More invited talks: · David Mikkelsen, "A quantitative account of electron energy transport in an NSTX plasma

  2. SciDAC Center for Simulation of Wave-Plasma Interactions - Iterated Finite-Orbit Monte Carlo Simulations with Full-Wave Fields for Modeling Tokamak ICRF Wave Heating Experiments - Final Report

    SciTech Connect (OSTI)

    Choi, Myunghee; Chan, Vincent S.

    2014-02-28

    This final report describes the work performed under U.S. Department of Energy Cooperative Agreement DE-FC02-08ER54954 for the period April 1, 2011 through March 31, 2013. The goal of this project was to perform iterated finite-orbit Monte Carlo simulations with full-wall fields for modeling tokamak ICRF wave heating experiments. In year 1, the finite-orbit Monte-Carlo code ORBIT-RF and its iteration algorithms with the full-wave code AORSA were improved to enable systematical study of the factors responsible for the discrepancy in the simulated and the measured fast-ion FIDA signals in the DIII-D and NSTX ICRF fast-wave (FW) experiments. In year 2, ORBIT-RF was coupled to the TORIC full-wave code for a comparative study of ORBIT-RF/TORIC and ORBIT-RF/AORSA results in FW experiments.

  3. A Compact Torus Fusion Reactor Utilizing a Continuously Generated Strings of CT's. The CT String Reactor, CTSR.

    SciTech Connect (OSTI)

    Hartman, C W; Reisman, D B; McLean, H S; Thomas, J

    2007-05-30

    A fusion reactor is described in which a moving string of mutually repelling compact toruses (alternating helicity, unidirectional Btheta) is generated by repetitive injection using a magnetized coaxial gun driven by continuous gun current with alternating poloidal field. An injected CT relaxes to a minimum magnetic energy equilibrium, moves into a compression cone, and enters a conducting cylinder where the plasma is heated to fusion-producing temperature. The CT then passes into a blanketed region where fusion energy is produced and, on emergence from the fusion region, the CT undergoes controlled expansion in an exit cone where an alternating poloidal field opens the flux surfaces to directly recover the CT magnetic energy as current which is returned to the formation gun. The CT String Reactor (CTSTR) reactor satisfies all the necessary MHD stability requirements and is based on extrapolation of experimentally achieved formation, stability, and plasma confinement. It is supported by extensive 2D, MHD calculations. CTSTR employs minimal external fields supplied by normal conductors, and can produce high fusion power density with uniform wall loading. The geometric simplicity of CTSTR acts to minimize initial and maintenance costs, including periodic replacement of the reactor first wall.

  4. Processes and properties of edge-localised instabilities in 2T 2MA plasmas in the Joint European Torus

    SciTech Connect (OSTI)

    Webster, A. J. Webster, S. J.

    2014-11-15

    During July 2012, 150 almost identical H-mode plasmas were consecutively created in the Joint European Torus, providing a combined total of approximately 8 minutes of steady-state plasma with 15?000 Edge Localised Modes (ELMs). In principle, each of those 15?000 ELMs are statistically equivalent. Here, the changes in edge density and plasma energy associated with those ELMs are explored, using the spikes in Beryllium II (527?nm) radiation as an indicator for the onset of an ELM. Clearly different timescales are observed during the ELM process. Edge temperature falls over a 2?ms timescale, edge density and pressure fall over a 5?ms timescale, and there is an additional 10?ms timescale that is consistent with a resistive relaxation of the plasma's edge. The statistical properties of the energy and density losses due to the ELMs are explored. For these plasmas the ELM energy (?E) is found to be approximately independent of the time between ELMs, despite the average ELM energy (??E?) and average ELM frequency (f) being consistent with the scaling of ??E??1/f. Instead, beyond the first 0.02 s of waiting time between ELMs, the energy losses due to individual ELMs are found to be statistically the same. Surprisingly no correlation is found between the energies of consecutive ELMs either. A weak link is found between the density drop and the ELM waiting time. Consequences of these results for ELM control and modelling are discussed.

  5. Influence of plasma diagnostics and constraints on the quality of equilibrium reconstructions on Joint European Torus

    SciTech Connect (OSTI)

    Gelfusa, M.; Gaudio, P.; Peluso, E. [Associazione EURATOM-ENEA, University of Rome “Tor Vergata”, Roma (Italy)] [Associazione EURATOM-ENEA, University of Rome “Tor Vergata”, Roma (Italy); Murari, A.; Baruzzo, M. [Consorzio RFX-Associazione EURATOM ENEA per la Fusione, I-35127 Padova (Italy)] [Consorzio RFX-Associazione EURATOM ENEA per la Fusione, I-35127 Padova (Italy); Lupelli, I.; Hawkes, N.; Brix, M.; Drozdov, V.; Meigs, A.; Romanelli, M. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)] [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Craciunescu, T. [EURATOM-MEdC Association, NILPRP, Bucharest (Romania)] [EURATOM-MEdC Association, NILPRP, Bucharest (Romania); Schmuck, S.; Sieglin, B. [Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, EURATOM Association, Wendelsteinstr.1, 17491 Greifswald (Germany)] [Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, EURATOM Association, Wendelsteinstr.1, 17491 Greifswald (Germany); Collaboration: JET-EFDA Contributors

    2013-10-15

    One of the main approaches to thermonuclear fusion relies on confining high temperature plasmas with properly shaped magnetic fields. The determination of the magnetic topology is, therefore, essential for controlling the experiments and for achieving the required performance. In Tokamaks, the reconstruction of the fields is typically formulated as a free boundary equilibrium problem, described by the Grad-Shafranov equation in toroidal geometry and axisymmetric configurations. Unfortunately, this results in mathematically very ill posed problems and, therefore, the quality of the equilibrium reconstructions depends sensitively on the measurements used as inputs and on the imposed constraints. In this paper, it is shown how the different diagnostics (Magnetics Measurements, Polarimetry and Motional Stark Effect), together with the edge current density and plasma pressure constraints, can have a significant impact on the quality of the equilibrium on JET. Results show that both the Polarimetry and Motional Stark Effect internal diagnostics are crucial in order to obtain reasonable safety factor profiles. The impact of the edge current density constraint is significant when the plasma is in the H-mode of confinement. In this plasma scenario the strike point positions and the plasma last closed flux surface can change even by centimetres, depending on the edge constraints, with a significant impact on the remapping of the equilibrium-dependent diagnostics and of pedestal physics studies. On the other hand and quite counter intuitively, the pressure constraint can severely affect the quality of the magnetic reconstructions in the core. These trends have been verified with several JET discharges and consistent results have been found. An interpretation of these results, as interplay between degrees of freedom and available measurements, is provided. The systematic analysis described in the paper emphasizes the importance of having sufficient diagnostic inputs and of properly validating the results of the codes with independent measurements.

  6. Digestion Experiments

    E-Print Network [OSTI]

    Fraps, G. S. (George Stronach)

    1908-01-01

    STATION. ppp DIGESTION EXPERIMENTS G. S. FRAPS, PH. D., CHEMIST. POSTOFFICE COLLEGE SL'ATION, HRAZOS COUNTY, TEXAS. AUSTIN, TEXAS: \\'ON BOECKMANN-JONES CO., PRLNTEHP. 1908 TEXAS AGRICULTURAL EXPERIMENT 8TArFIONS. OFFICERS. GOVERNING BOARD... OF CONTENTS . 1 . Digestibility of 1Caffir Corn. Milo Maize. and Molasses ....... G .................................... Ilcfinition of Terms 7 .................................. Method of Experiment 7 ............ Digestibility of Basal Ration of Meal...

  7. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

    SciTech Connect (OSTI)

    Myra, J. R. [Lodestar Research Corporation; Russell, D. A. [Lodestar Research Corporation; D'Ippolito, D. A. [Lodestar Research Corporation; Ahn, Joon-Wook [Oak Ridge National Laboratory (ORNL); Maingi, Rajesh [ORNL; Maqueda, R. J. [Princeton Plasma Physics Laboratory (PPPL); Lundberg, D. P. [Princeton Plasma Physics Laboratory (PPPL); Stotler, D. P. [Princeton Plasma Physics Laboratory (PPPL); Zweben, S. J. [Princeton Plasma Physics Laboratory (PPPL); Boedo, J. [University of California, San Diego; Umansky, M.W. [Lawrence Livermore National Laboratory (LLNL)

    2011-01-01

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat-flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature, and parallel heat flux are obtained from the simulation and compared with experimental results from the National Spherical Torus Experiment [S. M. Kaye et al., Phys. Plasmas 8, 1977 (2001)] to study the scaling of the heat-flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat-flux width for the low power H-mode discharges studied, while additional physics is required to fully explain the plasma current scaling of the SOL heat-flux width observed experimentally in higher power discharges. Intermittent separatrix-spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping versus emission are discussed.

  8. Experiment Profile:

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    their shapes, how galaxies cluster and the brightness of exploding stars called supernovae. WHY IS THIS EXPERIMENT NEEDED NOW? Research during the last decade using different...

  9. Divertor options for NSTX and NSTX-Upgrade Rajesh Maingi,

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Program Advisory Committee Meeting Princeton, NJ Feb. 3-5, 2010 College W&M Colorado Sch Mines Columbia U power exhaust sharing may be required ­ Gas puffing for radiative/detached divertor would be used techniques ­ High flux expansion divertors ­ Gas puffing for extra radiation and partial detachment

  10. NSTX Upgrade Project Execution Plan NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ..............................................................................................................................1 1.2.1 DOE-approved project documents:..............................................................................................1 1.2.2 DOE certified institutional systems or plans.......................................................................................................4 DOE Level I Milestones

  11. NSTX Upgrade Project Execution Plan NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    10/12/2012 Update to WBS Level 2 Threshold (top of page 20), Change DOE Federal Project Director ..............................................................................................................................1 1.2.1 DOE-approved project documents:..............................................................................................1 1.2.2 DOE certified institutional systems or plans

  12. Transformative Experiences

    E-Print Network [OSTI]

    Gering, Jon C.

    Transformative Experiences Internships & Field Schools Honors & Research Faculty Notables Alumni have at least one poten- tially transformative experi- ence - an opportunity to de- sign and carry out to be transformational are study abroad, internships, service learning, research, student-led learning, and lead- ership

  13. NSTX Program Overview andNSTX Program Overview and NSTX Upgrade Physics Design ProgressNSTX Upgrade Physics Design Progress

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    -B318, PPPL NSTXNSTX Supported by College W&M Colorado Sch Mines Columbia U CompX General Atomics INL in Upgrade 6. Develop normally-conducting radiation-tolerant magnets for ST applications · Desig

  14. Completed NSTX-U. After

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAuditsCluster Compatibilitydefault Changes from TukeyCryogenic panel (15 tons)

  15. Modeling the effect of lithium-induced pedestal profiles on scrape-off-layer turbulence and the heat flux width

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Russell, David A.; D'Ippolito, Daniel A.; Myra, James R.; Canik, John M.; Gray, Travis K.; Zweben, Stewart J.

    2015-09-01

    The effect of lithium (Li) wall coatings on scrape-off-layer (SOL) turbulence in the National Spherical Torus Experiment (NSTX) is modeled with the Lodestar SOLT (“SOL Turbulence”) code. Specifically, the implications for the SOL heat flux width of experimentally observed, Li-induced changes in the pedestal profiles are considered. The SOLT code used in the modeling has been expanded recently to include ion temperature evolution and ion diamagnetic drift effects. This work focuses on two NSTX discharges occurring pre- and with-Li deposition. The simulation density and temperature profiles are constrained, inside the last closed flux surface only, to match those measured inmore »the two experiments, and the resulting drift-interchange-driven turbulence is explored. The effect of Li enters the simulation only through the pedestal profile constraint: Li modifies the experimental density and temperature profiles in the pedestal, and these profiles affect the simulated SOL turbulence. The power entering the SOL measured in the experiments is matched in the simulations by adjusting “free” dissipation parameters (e.g., diffusion coefficients) that are not measured directly in the experiments. With power-matching, (a) the heat flux SOL width is smaller, as observed experimentally by infra-red thermography, and (b) the simulated density fluctuation amplitudes are reduced with Li, as inferred for the experiments as well from reflectometry analysis. The instabilities and saturation mechanisms that underlie the SOLT model equilibria are also discussed.« less

  16. IRRADIATION EXPERIMENTS &

    E-Print Network [OSTI]

    McDonald, Kirk

    IRRADIATION EXPERIMENTS & FACILITIES AT BNL: BLIP & NSLS II Peter Wanderer Superconducting MagnetV). Simultaneous irradiation and isotope production by increasing beam energy, placing irradiation target ahead of isotope production target · 117 Mev 140, 160, 180, 202 MeV · Irradiation at room temperature Alternative

  17. SUZAKU VIEW OF THE SWIFT/BAT ACTIVE GALACTIC NUCLEI. V. TORUS STRUCTURE OF TWO LUMINOUS RADIO-LOUD ACTIVE GALACTIC NUCLEI (3C 206 AND PKS 0707-35)

    SciTech Connect (OSTI)

    Tazaki, Fumie; Ueda, Yoshihiro; Terashima, Yuichi; Mushotzky, Richard F.; Tombesi, Francesco

    2013-07-20

    We present the results from broadband X-ray spectral analysis of 3C 206 and PKS 0707-35 with Suzaku and Swift/BAT, two of the most luminous unobscured and obscured radio-loud active galactic nuclei (AGNs) with hard X-ray luminosities of 10{sup 45.5} erg s{sup -1} and 10{sup 44.9} erg s{sup -1} (14-195 keV), respectively. Based on the radio core luminosity, we estimate that the X-ray spectrum of 3C 206 contains a significant ({approx}60% in the 14-195 keV band) contribution from the jet, while it is negligible in PKS 0707-35. We can successfully model the spectra with the jet component (for 3C 206), the transmitted emission, and two reflection components from the torus and the accretion disk. The reflection strengths from the torus are found to be R{sub torus}({identical_to} {Omega}/2{pi}) = 0.29 {+-} 0.18 and 0.41 {+-} 0.18 for 3C 206 and PKS 0707-35, respectively, which are smaller than those in typical Seyfert galaxies. Utilizing the torus model by Ikeda et al., we quantify the relation between the half-opening angle of a torus ({theta}{sub oa}) and the equivalent width of an iron-K line. The observed equivalent width of 3C 206, < 71 eV, constrains the column density in the equatorial plane to N{sub H}{sup eq} <10{sup 23} cm{sup -2}, or the half-opening angle to {theta}{sub oa} > 80 Degree-Sign if N{sub H}{sup eq} =10{sup 24} cm{sup -2} is assumed. That of PKS 0707-35, 72 {+-} 36 eV, is consistent with N{sub H}{sup eq} {approx}10{sup 23} cm{sup -2}. Our results suggest that the tori in luminous radio-loud AGNs are only poorly developed. The trend is similar to that seen in radio-quiet AGNs, implying that the torus structure is not different between AGNs with jets and without jets.

  18. Single crystal diamond detector measurements of deuterium-deuterium and deuterium-tritium neutrons in Joint European Torus fusion plasmas

    SciTech Connect (OSTI)

    Cazzaniga, C., E-mail: carlo.cazzaniga@mib.infn.it; Gorini, G.; Nocente, M. [Department of Physics “G. Occhialini,” University of Milano Bicocca, Piazza della Scienza 3, Milano (Italy) [Department of Physics “G. Occhialini,” University of Milano Bicocca, Piazza della Scienza 3, Milano (Italy); Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano (Italy); Sundén, E. Andersson; Binda, F.; Ericsson, G. [Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala (Sweden)] [Department of Physics and Astronomy, EURATOM-VR Association, Uppsala University, Uppsala (Sweden); Croci, G.; Grosso, G.; Cippo, E. Perelli; Tardocchi, M. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano (Italy)] [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano (Italy); Giacomelli, L.; Rebai, M. [Department of Physics “G. Occhialini,” University of Milano Bicocca, Piazza della Scienza 3, Milano (Italy)] [Department of Physics “G. Occhialini,” University of Milano Bicocca, Piazza della Scienza 3, Milano (Italy); Griesmayer, E. [Atominstitut, Vienna University of Technology (Austria)] [Atominstitut, Vienna University of Technology (Austria); Kaveney, G.; Syme, B. [Culham Centre for Fusion Energy, Culham OX143DB (United Kingdom)] [Culham Centre for Fusion Energy, Culham OX143DB (United Kingdom); Collaboration: JET-EFDA Contributors

    2014-04-15

    First simultaneous measurements of deuterium-deuterium (DD) and deuterium-tritium neutrons from deuterium plasmas using a Single crystal Diamond Detector are presented in this paper. The measurements were performed at JET with a dedicated electronic chain that combined high count rate capabilities and high energy resolution. The deposited energy spectrum from DD neutrons was successfully reproduced by means of Monte Carlo calculations of the detector response function and simulations of neutron emission from the plasma, including background contributions. The reported results are of relevance for the development of compact neutron detectors with spectroscopy capabilities for installation in camera systems of present and future high power fusion experiments.

  19. Simulation of tokamak SOL and divertor region including heat flux mitigation by gas puffing

    SciTech Connect (OSTI)

    Park, Jin Woo [Seoul National University, Seoul, S. Korea; Na, Y. S. [Seoul National University, Seoul, S. Korea; Hong, S. H. [National Fusion Research Institute, Daejon, South Korea; Ahn, J.W. [Oak Ridge National Laboratory (ORNL); Kim, D. K. [Agency Def Dev, Taejon, South Korea; Han, Hyunsun [National Fusion Research Institute, Taejon, South Korea; Shim, Seong Bo [Pusan National University, Busan, Korea; Lee, Hae June [Pusan National University, Busan, Korea

    2012-01-01

    Two-dimensional (2D), scrape-off layer (SOL)-divertor transport simulations are performed using the integrated plasma-neutral-impurity code KTRAN developed at Seoul National University. Firstly, the code is applied to reproduce a National Spherical Torus eXperiment (NSTX) discharge by using the prescribed transport coefficients and the boundary conditions obtained from the experiment. The plasma density, the heat flux on the divertor plate, and the D (alpha) emission rate profiles from the numerical simulation are found to follow experimental trends qualitatively. Secondly, predictive simulations are carried out for the baseline operation mode in Korea Superconducting Tokamak Advanced Research (KSTAR) to predict the heat flux on the divertor target plates. The stationary peak heat flux in the KSTAR baseline operation mode is expected to be 6.5 MW/m(2) in the case of an orthogonal divertor. To study the mitigation of the heat flux, we investigated the puffing effects of deuterium and argon gases. The puffing position is assumed to be in front of the strike point at the outer lower divertor plate. In the simulations, mitigation of the peak heat flux at the divertor target plates is found to occur when the gas puffing rate exceeds certain values, similar to 1.0 x 10(20) /s and similar to 5.0 x 10(18) /s for deuterium and argon, respectively. Multi-charged impurity transport is also investigated for both NSTX and KSTAR SOL and divertor regions.

  20. On The Anomalous Fast Ion Energy Diffusion in Toroidal Plasmas Due to Cavity Modes

    SciTech Connect (OSTI)

    N.N. Gorelenkov, N.J. Fisch and E. Fredrickson

    2010-03-09

    An enormous wave-particle diffusion coefficient along paths suitable for alpha channeling had been deduced in mode converted ion Bernstein wave experiments on Tokamak Fusion Test Reactor (TFTR) the only plausible explanation advanced for such a large diffusion coefficient was the excitation of internal cavity modes which induce particle diffusion along identical diffusion paths, but at much higher rates. Although such a mode was conjectured, it was never observed. However, recent detailed observations of high frequency compressional Alfven eigenmodes (CAEs) on the National Spherical torus Experiment (NSTX) indirectly support the existence of the related conjectured modes on TFTR. The eigenmodes responsible for the high frequency magnetic activity can be identified as CAEs through the polarization of the observed magnetic field oscillations in NSTX and through a comparison with the theoretically derived freuency dispersion relation. Here, we show how these recent observations of high frequency CAEs lend support to this explanation of the long-standing puzzle of anomalous fast ion energy diffusion on TFTR. The support of the conjecure that these internal modes could have caused the remarkable ion energy diffusion on TFTR carries significant and favorable implications for the possibilities in achieving the alpha channeling effect with small injected power in a tokamak reactor.

  1. Turbulent Transport and the Scrape-off-layer Width

    SciTech Connect (OSTI)

    Myra, J. R. [Lodestar Research Corporation; Russell, D. A. [Lodestar Research Corporation; Ahn, J.W. [Oak Ridge National Laboratory (ORNL); D'Ippolito, D. A. [Lodestar Research Corporation; Maingi, Rajesh [ORNL; Maqueda, R. J. [Nova Photonics, Princeton, NJ; Lundberg, D. P. [Princeton Plasma Physics Laboratory (PPPL); Stotler, D. P. [Princeton Plasma Physics Laboratory (PPPL); Zweben, S. J. [Princeton Plasma Physics Laboratory (PPPL); Umansky, M. [Lawrence Livermore National Laboratory (LLNL)

    2011-01-01

    The two-dimensional fluid turbulence code SOLT is employed to study the role of midplane turbulence on the scrape-off-layer (SOL) heat flux width of tokamak plasmas. The physics simulated includes curvature-driven-interchange modes, sheath losses, and perpendicular turbulent diffusive and convective (blob) transport. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from the simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL width for the low power ELM-free H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL width observed experimentally in higher power discharges. Additional simulations predict a transition to a convectively-dominated SOL at critical values of power and connection length.

  2. Ideal magnetohydrodynamic simulations of unmagnetized dense plasma jet injection into a hot strongly magnetized plasma

    E-Print Network [OSTI]

    Liu, Wei

    2010-01-01

    We present results from three-dimensional ideal magnetohydrodynamic simulations of unmagnetized dense plasma jet injection into a hot strongly magnetized plasma, with the aim of providing insight into core fueling of a tokamak with parameters relevant for ITER (International Thermonuclear Experimental Reactor) and NSTX (National Spherical Torus Experiment). Unmagnetized jet injection is similar to compact toroid injection but with higher possible injection density and total mass, as well as a potentially smaller footprint for the injector hardware. Our simulation results show that the unmagnetized dense jet is quickly magnetized upon injection. The penetration depth of the jet into the tokamak plasma is mostly dependent on the jet's initial kinetic energy while the jet's magnetic field determines its interior evolution. A key requirement for spatially precise fueling is for the jet's slowing-down time to be less than the time for the perturbed tokamak magnetic flux to relax due to magnetic reconnection. Thus ...

  3. Comment on “Magnetic geometry and physics of advanced divertors: The X-divertor and the snowflake” [Phys. Plasmas 20, 102507 (2013)

    SciTech Connect (OSTI)

    Ryutov, D. D. Cohen, R. H.; Rognlien, T. D.; Soukhanovskii, V. A.; Umansky, M. V.

    2014-05-15

    In the recently published paper “Magnetic geometry and physics of advanced divertors: The X-divertor and the snowflake” [Phys. Plasmas 20, 102507 (2013)], the authors raise interesting and important issues concerning divertor physics and design. However, the paper contains significant errors: (a) The conceptual framework used in it for the evaluation of divertor “quality” is reduced to the assessment of the magnetic field structure in the outer Scrape-Off Layer. This framework is incorrect because processes affecting the pedestal, the private flux region and all of the divertor legs (four, in the case of a snowflake) are an inseparable part of divertor operation. (b) The concept of the divertor index focuses on only one feature of the magnetic field structure and can be quite misleading when applied to divertor design. (c) The suggestion to rename the divertor configurations experimentally realized on NSTX (National Spherical Torus Experiment) and DIII-D (Doublet III-D) from snowflakes to X-divertors is not justified: it is not based on comparison of these configurations with the prototypical X-divertor, and it ignores the fact that the NSTX and DIII-D poloidal magnetic field geometries fit very well into the snowflake “two-null” prescription.

  4. PREPARED FOR THE U.S. DEPARTMENT OF ENERGY, UNDER CONTRACT DE-AC02-76CH03073

    E-Print Network [OSTI]

    Publications and Reports web site in Calendar Year 2000. The home page for PPPL Reports and Publications is for the study of plasma confinement, heating, and current drive in a low aspect ratio, spherical torus (ST tokamaks, and could provide a pathway to the realization of a practical fusion power source. NSTX achieved

  5. Fueling Requirements for Steady State high butane current fraction discharges

    SciTech Connect (OSTI)

    R.Raman

    2003-10-08

    The CT injector originally used for injecting CTs into 1T toroidal field discharges in the TdeV tokamak was shipped PPPL from the Affiliated Customs Brokers storage facility in Montreal during November 2002. All components were transported safely, without damage, and are currently in storage at PPPL, waiting for further funding in order to begin advanced fueling experiments on NSTX. The components are currently insured through the University of Washington. Several technical presentations were made to investigate the feasibility of the CT injector installation on NSTX. These technical presentations, attached to this document, were: (1) Motivation for Compact Toroida Injection in NSTX; (2) Assessment of the Engineering Feasibility of Installing CTF-II on NSTX; (3) Assessment of the Cost for CT Installation on NSTX--A Peer Review; and (4) CT Fueling for NSTX FY 04-08 steady-state operation needs.

  6. Visualizing and Quantifying Blob Characteristics on NSTX

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    . This work was supported by DOE Contract DEAC0209CH11466. #12;Approach · Automate the fitting and tracking Separatrix · History ­ Parent blob # (where it came from)

  7. Michael Bell for the NSTX Research Team

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTXNSTX Supported by College W&M Colorado Sch Mines Columbia U CompX General Atomics INL Johns Hopkins U accumulation increases radiated power and Zeff H. Kugel, B. LeBlanc, R.E. Bell #12;M.G. Bell / PPPL Theory Dept

  8. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Chit Review Board (designated by Run Coordinator) Note: Step 2 ­ 10mg/min and 12.5min clock cycle levels of Li evaporation. Note: Step 5 ­ use SGI (5000 Torr), pulse durations loaded from shot 134134 SGI varying plasma parameters (beam power, Ip, fueling) and deposition will be studied. The key figure

  9. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    with evaporation rate = 20mg/min i. Use LITER shutter to fix evaporation duration at 8min with 10min shot cycle 3 for improved pedestal data while ensuring heat load on HHFW antenna is acceptable 4. Increase evaporation rate fueling with SGI fueling to increase density (8 shots) ii. Optimizing beam power and timing to avoid early

  10. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    shots) 1. Start with evaporation rate = 20mg/min for 10mins, 12 min shot cycle, no He glow i. Use XP836 heating power, thereby providing data for the ITPA IOS group for validating beam current drive models early NBI power if beta-limit is reached, but maintain early H-mode 2. Start n=3 EF correction at t=20ms

  11. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    evaporation rate for 8.5min, 1 min pump out before shot (10 min clock cycle). Ensure that there is no NBI gasA. A lithium evaporation rate of 10-15mg/min would be used with no HeGDC between shots. A warm Li divertor rectifier power supply. Several high-current double-null discharges, but slightly biased to be upper null

  12. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    /min Li evaporation. · No HeGDC between shots. · Shorten shot to 500-600 ms to reduce shot cycle to 10 is to study the effect of rotation on the L-H threshold power. n=3 braking will be used to vary the rotation) and at higher rotation (NHTX, ST-CTF). 3. Experimental run plan · Establish L-H threshold power in low

  13. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Apply lithium evaporation at a rate of 200 mg/shot and run on a 10 min shot cycle. One lithium powder-Mode power threshold, ELMs and MHD activity. 2. Theoretical/empirical justification This work) Perform power scan 4.5, 3.5, 3, 2 MW to get H-Mode threshold for LSN 6 16 5) Run USN shot 117750 repeating

  14. Eric Fredrickson For the NSTX Team

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    PPPL PSI Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Irvine UCLA UCSD U Colorado U Illinois U required for a given plasma current, but also leaves little room for the solonoid, shielding of TF

  15. Work Authorization Document NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    -NBI-Control & Instm 5 08JUN10A 08JUN10A 14JUN10A 14JUN10A 0 0.00 100 0.00 0.00 2475-0004 FMEA Analysis

  16. Work Authorization Document NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    01JUN10A 0 0.00 100 0.00 0.00 1000-0008 Fault, FMEA evaluation and analyses 21 03MAY10A 03MAY10A 0110A 25FEB11 18MAY11 -58 147 18,651.56 75 13,823.15 18,430.86 1000-0017 Fault, FMEA analyses (LOE) 220

  17. NSTX Contributions to Burning Plasma Studies

    E-Print Network [OSTI]

    Eigenmode (CAE) Global Alfvén Eigenmode (GAE) Hole-clump pair New modes predicted to be present on ITER New mode - likely unique to ST? Multiple modes Relevant to ITER EPM TAE GAE CAE 1000 100 10 0.15 0.20 0 with resonant overlap / chirping ­ Super-Alfvénic driven: · CAEs (nonlinear heating of thermal ions?) · GAEs

  18. Work Authorization Document NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    , bellows and organ pipes; the fabrication of Center Stack support legs; the procurementJAN14 06JAN14 0 51 904,627.54 139,894.87 167,190.11 1307-1010 Complete CAD Detail & Assy Drawings & Assy Drawings (Final) 48* 01FEB11* 31MAR11A 07APR11 07JUN11 -42 126 29,478.76 50 14,739.38 29

  19. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    to observe the heating/CD effectiveness in sustaining the plasma current. Starting with 250 kA at tflattop = 40 ms. A k|| = 14 m-1 heating phasing will be used first, and then k|| = 10 m-1 co-CD, heating, and cntr-CD. Advantage will be taken of the RF voltage-power control to reduce the injected power

  20. Princeton Plasma Physics Laboratory NSTX Machine Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    : Normal plasma ops requirements - Sources A, B, and C at ~90kV. #12;OP-XMP-60 4 / 6 5. Sign off at run): Off Phasing: Duration (s): CHI: Off Bank capacitance (mF): LITER: On or Off (either way) Either: List gaps, , , heating, fuelling, etc. as appropriate. Accurately label the ske

  1. Work Authorization Document NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    (top and bottom) 6 04JAN13 04JAN13 11JAN13 11JAN13 0 161 40,466.88 0.00 0.00 8250-113 Support lower support structure 4 14JAN13 14JAN13 17JAN13 17JAN13 0 161 26,977.92 0.00 0.00 8250-117 lift old pedestal 5 22JAN13 22JAN13 28JAN13 28JAN13 0 212 20,392.80 0.00 0.00 8250-122 Purchase passive plate bolts

  2. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Author: G. Taylor Date ATI ­ ET Group Leader: G. Taylor Date RLM - Run Coordinator: E. Fredrickson Date-Driven 100% Non-Inductive H-Mode Plasma No. OP-XP-1010 AUTHORS: G. Taylor, D. Mueller, J.C. Hosea, S. Gerhardt, C. Kessel, B.P. LeBlanc, C.K. Phillips, S. Zweben, R. Maingi, P.M. Ryan, R. Maingi DATE: February

  3. Princeton Plasma Physics Laboratory NSTX Experimental Proposal

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Authors: P. Ryan Date 7/7/09 ATI ­ ET Group Leaders: G. Taylor Date 7/7/09 RLM - Run Coordinator: R. Raman. Hosea, R. Bell, B. LeBlanc, C.K. Phillips, G. Taylor, J. Wilgen, J.R. Wilson DATE: June 25, 2009 1. Theoretical/ empirical justification This XP addresses Research Milestone R(10-2) Characterize High

  4. Work Authorization Document NSTX Upgrade Project

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    0 1,487 1,538,883.45 398,403.27 398,403.27 Job: 7200 - Center Stack Management-DUDEK Subtotal 1,222 02NOV09A 02NOV09A 30SEP14 30SEP14 0 1,487 1,538,883.45 398,403.27 398,403.27 Project Management 7200

  5. Energetic Particle Physics In Fusion Research In Preparation For Burning Plasma Experiments

    SciTech Connect (OSTI)

    Gorelenkov, Nikolai N

    2013-06-01

    The area of energetic particle (EP) physics of fusion research has been actively and extensively researched in recent decades. The progress achieved in advancing and understanding EP physics has been substantial since the last comprehensive review on this topic by W.W. Heidbrink and G.J. Sadler [1]. That review coincided with the start of deuterium-tritium (DT) experiments on Tokamak Fusion Test reactor (TFTR) and full scale fusion alphas physics studies. Fusion research in recent years has been influenced by EP physics in many ways including the limitations imposed by the "sea" of Alfven eigenmodes (AE) in particular by the toroidicityinduced AEs (TAE) modes and reversed shear Alfven (RSAE). In present paper we attempt a broad review of EP physics progress in tokamaks and spherical tori since the first DT experiments on TFTR and JET (Joint European Torus) including helical/stellarator devices. Introductory discussions on basic ingredients of EP physics, i.e. particle orbits in STs, fundamental diagnostic techniques of EPs and instabilities, wave particle resonances and others are given to help understanding the advanced topics of EP physics. At the end we cover important and interesting physics issues toward the burning plasma experiments such as ITER (International Thermonuclear Experimental Reactor).

  6. Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 1999

    SciTech Connect (OSTI)

    Virginia Finley

    2001-04-20

    The results of the 1999 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and non-radioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 1999. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program is to create innovations to make fusion power a practical reality--an alternative energy source. 1999 marked the first year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion reactors. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. The 1999 performance of the Princeton Plasma Physics Laboratory was rated ''outstanding'' by the U.S. Department of Energy in the Laboratory Appraisal report issued early in 2000. The report cited the Laboratory's consistently excellent scientific and technological achievements, its successful management practices, and included high marks in a host of other areas including environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of non-radiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report.

  7. Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 2000

    SciTech Connect (OSTI)

    Virginia L. Finley

    2002-04-22

    The results of the 2000 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and nonradioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 2000. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program is to create innovations to make fusion power a practical reality -- an alternative energy source. The year 2000 marked the second year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion power plants. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. In 2000, PPPL's radiological environmental monitoring program measured tritium in the air at on-site and off-site sampling stations. PPPL is capable of detecting small changes in the ambient levels of tritium by using highly sensitive monitors. The operation of an in-stack monitor located on D-site is a requirement of the National Emission Standard for Hazardous Air Pollutants (NESHAPs) regulations with limits set by the Environmental Protection Agency (EPA). Also included in PPPL's radiological environmental monitoring program, are precipitation, surface, ground, a nd waste water monitoring. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the D-site stack; the data are presented in this report.

  8. Portable controls experiments

    E-Print Network [OSTI]

    Larson, Richard Winston

    2012-01-01

    Experiments for controls classes like MIT's 2.004 require large lab setups and expensive equipment such as oscilloscopes and function generators. We developed a series of controls experiments based on National Instruments' ...

  9. Experiments: Preparation and Measurement

    E-Print Network [OSTI]

    Neumaier, Arnold

    the experimental set­up und the results of performing the experiment. Again, this is part of human cultureExperiments: Preparation and Measurement by Arnold Neumaier, Vienna March 1996 Abstract Introduction Experiments, properly arranged, provide information about a physical system by suitable

  10. Science and Technology of the 10-MA Spherical Tori

    SciTech Connect (OSTI)

    Peng, Y-K.M.

    1999-11-14

    The Spherical Torus (ST) configuration has recently emerged as an example of confinement concept innovation that enables attractive steps in the development of fusion energy. The scientific potential for the ST has been indicated by recent encouraging results from START,2 CDX-U, and HIT. The scientific principles for the D-fueled ST will soon be tested by NSTX (National Spherical Torus Experiment3) in the U.S. and MAST (Mega-Amp Spherical Tokamak4) in the U.K. at the level of l-2 MA in plasma current. More recently, interest has grown in the U.S. in the possibility of near-term ST fusion burn devices at the level of 10 MA in plasma current. The missions for these devices would be to test burning plasma performance in a small, pulsed D-T-fueled ST (i.e., DTST) and to develop fusion energy technologies in a small steady state ST-based Volume Neutron Source (VNS). This paper reports the results of analysis of the key science and technology issues for these devices.

  11. Double Beta Decay Experiments

    SciTech Connect (OSTI)

    Nanal, Vandana [Dept. of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Mumbai 400 005 (India)

    2011-11-23

    At present, neutrinoless double beta decay is perhaps the only experiment that can tell us whether the neutrino is a Dirac or a Majorana particle. Given the significance of the 0{nu}{beta}{beta}, there is a widespread interest for these rare event studies employing a variety of novel techniques. This paper describes the current status of DBD experiments. The Indian effort for an underground NDBD experiment at the upcoming INO laboratory is also presented.

  12. The Fusion Advanced Studies Torus (FAST): a proposal for an ITER satellite facility in support of the development of fusion energy

    E-Print Network [OSTI]

    Zonca, Fulvio

    provided with a dominant ion cyclotron resonance heating system (ICRH; 30 MW on the plasma). Moreover, the experiment foresees the use of 6 MW of lower hybrid (LHCD), essentially for plasma control and for non-inductive current drive, and of electron cyclotron resonance heating (ECRH, 4 MW) for localized electron heating

  13. The Fusion Advanced Studies Torus (FAST): a Proposal for an ITER Satellite Facility in Support of the Development of Fusion Energy

    E-Print Network [OSTI]

    Zonca, Fulvio

    , the project is based on a dominant Ion Cyclotron Resonance Heating system (ICRH; 30 MW coupled to the plasma). Moreover, the experiment foresees 6 MW of Lower Hybrid (LH), essentially for plasma control and for non-inductive current drive, and of Electron Cyclotron Resonance Heating (ECRH; 4MW) for localized electron heating

  14. Nuclear Physics: Experiment Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Accelerator and Experimental Schedule Beam Time Request Form Experiment Scheduling and General Information Radiation Budget Form (pdf) Interactive beam request form (for contact...

  15. Nuclear Physics: Experiment Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks Additional Information Computing at JLab Operations Logbook Experiment...

  16. Franklin: User Experiences

    SciTech Connect (OSTI)

    National Energy Research Supercomputing Center; He, Yun; Kramer, William T.C.; Carter, Jonathan; Cardo, Nicholas

    2008-05-07

    The newest workhorse of the National Energy Research Scientific Computing Center is a Cray XT4 with 9,736 dual core nodes. This paper summarizes Franklin user experiences from friendly early user period to production period. Selected successful user stories along with top issues affecting user experiences are presented.

  17. International Experience Singapore 2014

    E-Print Network [OSTI]

    Subramanian, Venkat

    , energy and environmental issues in India, alternative energy and technology in China and Hong KongInternational Experience Singapore 2014 Department of Energy, Environmental And Chemical Experience Program is part of the McDonnell International Scholars Academy Global Energy & Environment

  18. The Neutron EDM Experiment

    E-Print Network [OSTI]

    P. G. Harris

    2007-12-05

    The neutron EDM experiment has played an important part over many decades in shaping and constraining numerous models of CP violation. This review article discusses some of the techniques used to calculate EDMs under various theoretical scenarios, and highlights some of the implications of EDM limits upon such models. A pedagogical introduction is given to the experimental techniques employed in the recently completed ILL experiment, including a brief discussion of the dominant systematic uncertainties. A new and much more sensitive version of the experiment, which is currently under development, is also outlined.

  19. General relativity and experiment

    E-Print Network [OSTI]

    T. Damour

    1994-12-08

    The confrontation between Einstein's theory of gravitation and experiment is summarized. Although all current experimental data are compatible with general relativity, the importance of pursuing the quest for possible deviations from Einstein's theory is emphasized.

  20. Experiment Scheduling Committee

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Experiment Scheduling Committee Title Name Phome Email Deputy Director for Research Bob McKeown (757) 269-6481 bmck@jlab.org Physics Division AD (co-chair) Rolf Ent (757) 269-7373...

  1. The GLUEX Experiment

    SciTech Connect (OSTI)

    M.R. Shepherd

    2009-12-01

    The GLUEX experiment, to be constructed in the new Hall D at Jefferson Lab as part of the 12 GeV upgrade, will utilize a linearly polarized 9 GeV photon beam, produced via coherent bremsstrahlung radiation off of a diamond wafer, incident on a proton target to conduct a search for exotic hybrid mesons. A summary of the physics motivation for the experiment and the key factors that drive the design of the detector and beam line is presented.

  2. The MAJORANA Experiment

    E-Print Network [OSTI]

    The MAJORANA Collaboration

    2011-09-22

    The MAJORANA collaboration is actively pursuing research and development aimed at a tonne-scale 76Ge neutrinoless double-beta decay) experiment. The current, primary focus is the construction of the MAJORANA DEMONSTRATOR experiment, an R&D effort that will field approximately 40kg of germanium detectors with mixed enrichment levels. This article provides a status update on the construction of the DEMONSTRATOR.

  3. The MAJORANA Experiment

    SciTech Connect (OSTI)

    Aguayo Navarrete, Estanislao; Avignone, F. T.; Back, Henning O.; Barabash, Alexander S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Collar, J. I.; Combs, Dustin C.; Cooper, R. J.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, Steven R.; Esterline, James H.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor M.; Giovanetti, G. K.; Green, Matthew P.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, R.; Hime, Andrew; Hoppe, Eric W.; Horton, Mark; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keillor, Martin E.; Keller, C.; Kephart, Jeremy D.; Kidd, Mary; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaFerriere, Brian D.; LaRoque, B. H.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Mei, Dong-Ming; Merriman, Jason H.; Miller, M. L.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; Overman, Nicole R.; Phillips, D.; Poon, Alan; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Sobolev, V.; Steele, David; Strain, J.; Thomas, K.; Timkin, V.; Tornow, W.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, John; Wolfe, B. A.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir; Zhang, C.

    2011-10-01

    The Majorana collaboration is actively pursuing research and development aimed at a tonne-scale {sup 76}Ge neutrinoless double-beta decay ({beta}{beta}(0{nu})-decay) experiment. The current, primary focus is the construction of the Majorana Demonstrator experiment, an R and D effort that will field approximately 40 kg of germanium detectors with mixed enrichment levels. This article provides a status update on the construction of the Demonstrator.

  4. The Majorana Experiment

    SciTech Connect (OSTI)

    Aguayo, E.; Fast, J. E.; Hoppe, E. W.; Keillor, M. E.; Kephart, J. D.; Kouzes, R. T.; LaFerriere, B. D.; Merriman, J. H.; Orrell, J. L.; Overman, N. R. [Pacific Northwest National Laboratory, Richland, WA (United States); Avignone, F. T. III [Department of Physics and Astronomy, University of South Carolina, Columbia, SC (United States); Oak Ridge National Laboratory, Oak Ridge, TN (United States); Back, H. O. [Department of Physics, North Carolina State University, Raleigh, NC (United States); Triangle Universities Nuclear Laboratory, Durham, NC (United States); Barabash, A. S.; Konovalov, S. I.; Vanyushin, I.; Yumatov, V. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bergevin, M.; Chan, Y.-D.; Detwiler, J. A.; Loach, J. C. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); and others

    2011-12-16

    The Majorana collaboration is actively pursuing research and development aimed at a tonne-scale {sup 76}Ge neutrinoless double-beta decay ({beta}{beta}(0{nu})-decay) experiment. The current, primary focus is the construction of the Majorana Demonstrator experiment, an R and D effort that will field approximately 40 kg of germanium detectors with mixed enrichment levels. This article provides a status update on the construction of the Demonstrator.

  5. NSTX Weekly Report (May 21, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    the town meeting are downloadable from: http://cer.ucsd.edu/ATMPMI2010/program.shtml (J. Menard. Stratton, R. Kaita) Jon Menard and Rajesh Maingi (ORNL) participated in the ARIES Town Meeting on "Edge

  6. NSTX Weekly Report (November 19, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    good progress on MSE-LIF diagnostic and Switching Power Amplifier upgrade (SPA-2) installations. Access Tiles - A Final Design Review for installing molybdenum plates on the row-1 tiles of the inner divertor

  7. NSTX Weekly Report (July 16, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    to improve access. IE Power Corp completed the manufacture of a new Switching Power Amplifier (SPA) supply of a conceptual design for the ITER PCS. First, we were given up to date information on the progress on CODAC on the conceptual design of the different parts of these groups was arranged on volunteering basis. As part

  8. NSTX Weekly Report (July 2, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    with the successful final design review of the 2nd Switching Power Amplifier (SPA). (T. Egebo) Charles Skinner a second Switching Power Amplifier (SPA) supply to provide individual RWM coil power feeds was successfully Projects 3rd Quarter milestone engineering and design of the facility upgrades was complete on June 30

  9. NSTX Weekly Report (June 18, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    as well as dual probe lithium evaporation. Commissioning of new coil protection circuitry and the integrated system testing required for combined PF4 and PF5 coil operation were successfully completed on the vessel next week for a period of extended lithium evaporation in preparation for an upcoming Liquid

  10. NSTX Weekly Report (December 17, 2010) FY 2011 NSTX plasma operations started on October 4, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    , and poloidal velocities and their radial shearing rate are well correlated with the fraction of D-alpha light Lithium Divertor (LLD) plates and surrounding tiles, and the start of in-vessel tile sanding Switching Power Amplifier system have been installed and tested this week, and helium and water piping

  11. NSTX Weekly Report (Mar. 12, 2010) FY 2010 NSTX plasma operations

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    with the successful completion of the vacuum vessel bake, and the ongoing preparations for field coil power testing vacuum vessel. Also this week, new fiber-optic cabling was installed in the test cell for network, and focuses on the role of shape (drsep, triangularity), as well as comparing the PLH with rf vs NBI power. (R

  12. Gyroharmonic conversion experiments

    SciTech Connect (OSTI)

    Hirshfield, J.L.; LaPointe, M.A.; Ganguly, A.K. [Omega-P, Inc., New Haven, Connecticut 06520 (United States); LaPointe, M.A. [Yale University, New Haven, Connecticut 06511 (United States)

    1999-05-01

    Generation of high power microwaves has been observed in experiments where a 250{endash}350 kV, 20{endash}30 A electron beam accelerated in a cyclotron autoresonance accelerator (CARA) passes through a cavity tuned gyroharmonic) and at 8.6 GHz (3rd harmonic) will be described. Theory indicates that high conversion efficiency can be obtained for a high quality beam injected into CARA, and when mode competition can be controlled. Comparisons will be made between the experiments and theory. Planned 7th harmonic experiments will also be described, in which phase matching between the TE-72 mode at 20 GHz, and the TE-11 mode at 2.86 GHz, allows efficient 20 GHz co-generation within the CARA waveguide itself. {copyright} {ital 1999 American Institute of Physics.}

  13. Gyroharmonic conversion experiments

    SciTech Connect (OSTI)

    Hirshfield, J. L.; LaPointe, M. A. [Omega-P, Inc., New Haven, Connecticut 06520 (United States); Yale University, New Haven, Connecticut 06511 (United States); Ganguly, A. K. [Omega-P, Inc., New Haven, Connecticut 06520 (United States)

    1999-05-07

    Generation of high power microwaves has been observed in experiments where a 250-350 kV, 20-30 A electron beam accelerated in a cyclotron autoresonance accelerator (CARA) passes through a cavity tuned gyroharmonic) and at 8.6 GHz (3rd harmonic) will be described. Theory indicates that high conversion efficiency can be obtained for a high quality beam injected into CARA, and when mode competition can be controlled. Comparisons will be made between the experiments and theory. Planned 7th harmonic experiments will also be described, in which phase matching between the TE-72 mode at 20 GHz, and the TE-11 mode at 2.86 GHz, allows efficient 20 GHz co-generation within the CARA waveguide itself.

  14. Irish Potato Fertilizer Experiments

    E-Print Network [OSTI]

    Hotchkiss, W.S.; Kyle, E. J. (Edwin Jackson)

    1908-01-01

    - ERS, 191 4 FIELD B I., Nitrogen; P.; Phosphoric aci'd; K., potash. lo~~.--The price of fertilizer as in 1906, was as follows: Cotton Seed ~eal,' $26.00 per ton; Acid Phospnate, $20.00 per ton; Sulphate ;h. $55.00 Der ton. Yield Marketabe Bushels.... BULLETIN NO 101 January, 1908. ish Potato Fertilizer Experiments - Postoffice, COLLEGE STATION, BRAZOS COUNTY, TEXAS. TEXAS AGRICULTURAL EXPERIMENT STATIONS OFFICERS. GOVERNING BOARD. (Board of Directors A. & M. College.) \\ - -- K. K. LEGGETT...

  15. Measuring Programming Experience Janet Feigenspan,

    E-Print Network [OSTI]

    Kaestner, Christian

    Measuring Programming Experience Janet Feigenspan, University of Magdeburg Christian K of Duisburg-Essen Abstract--Programming experience is an important confound- ing parameter in controlled experiments regarding program comprehension. In literature, ways to measure or control pro- gramming

  16. Measuring Programming Experience Janet Feigenspan,

    E-Print Network [OSTI]

    Apel, Sven

    Measuring Programming Experience Janet Feigenspan, University of Magdeburg, Germany Christian K Hanenberg, University of Duisburg-Essen, Germany Abstract--Programming experience is an important confound- ing parameter in controlled experiments regarding program comprehension. In literature, ways

  17. Hog Feeding Experiments

    E-Print Network [OSTI]

    Burns, John C.

    1910-01-01

    ................................................................................. ~eriment,s Nos. 111 and IV 17 I ...................................................................................... ,,,,proved Hogs vs. Scrubs 19 I Corn vs. Rice Bran vs. Spanish Peanuts ........................................................... 22... 1 ! .................................................................................................................. Summary. 33 I I [Blank Page in Original Bulletin] HOG FEEDING EXPERIMENTS. BY JOHN C. BURNS, DEPARTMENT OF ANIMAL...

  18. The Majorana Experiment

    E-Print Network [OSTI]

    V. E. Guiseppe; for the Majorana Collaboration

    2010-12-30

    The Majorana Collaboration is assembling an array of HPGe detectors to search for neutrinoless double-beta decay in Ge-76. Initially, Majorana aims to construct a prototype module to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module are presented.

  19. The Majorana Experiment

    SciTech Connect (OSTI)

    Aalseth, Craig E.; Aguayo Navarrete, Estanislao; Amman, M.; Avignone, F. T.; Back, Henning O.; Bai, Xinhua; Barabash, Alexander S.; Barbeau, P. S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Bugg, William; Burritt, Tom H.; Busch, Matthew; Capps, Greg L.; Chan, Yuen-Dat; Collar, J. I.; Cooper, R. J.; Creswick, R.; Detwiler, Jason A.; Diaz, J.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Ely, James H.; Esterline, James H.; Farach, H. A.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor M.; Giovanetti, G. K.; Green, M.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Harper, Gregory; Hazama, R.; Henning, Reyco; Hime, Andrew; Hong, H.; Hoppe, Eric W.; Hossbach, Todd W.; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keillor, Martin E.; Keller, C.; Kephart, Jeremy D.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaRoque, B. H.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Medlin, D.; Mei, Dong-Ming; Miley, Harry S.; Miller, M. L.; Mizouni, Leila; Myers, Allan W.; Nomachi, Masaharu; Orrell, John L.; Peterson, David; Phillips, D.; Poon, Alan; Perevozchikov, O.; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Reid, Douglas J.; Rielage, Keith; Robertson, R. G. H.; Rodriguez, Larry; Ronquest, M. C.; Salazar, Harold; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Sobolev, V.; Steele, David; Strain, J.; Swift, Gary; Thomas, K.; Timkin, V.; Tornow, W.; Van Wechel, T. D.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Wolfe, B. A.; Xiang, W.; Yakushev, E.; Yaver, Harold; Young, A.; Yu, Chang-Hong; Yumatov, V.; Zhang, C.

    2011-08-01

    The Majorana Collaboration is assembling an array of HPGe detectors to search for neutrinoless double-beta decay in 76Ge. Initially, Majorana aims to construct a prototype module to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module are presented.

  20. The MAJORANA Experiment

    SciTech Connect (OSTI)

    Guiseppe, V.E.; Keller, C.; Mei, D-M; Perevozchikov, O.; Perumpilly, G.; Thomas, K.; Xiang, W.; Zhang, C.; Aalseth, C.E.; Aguayo, E.; Ely, J.; Fast, J.E.; Hoppe, E.W.; Hossbach, T.W.; Keillor, M.; Kephart, J.D.; Kouzes, R.; Miley, H.S.; Mizouni, L.; Myers, A.W.; Reid, D.; Amman, M.; Bergevin, M.; Chan, Y-D; Detwiler, J.A.; Loach, J.C.; Luke, P.N.; Martin, R.D.; Poon, A.W.P.; Prior, G.; Vetter, K.; Yaver, H.; Avignone, F.T. III; Creswick, R.; Farach, H.; Mizouni, L.; Avignone, Frank Titus; Bertrand Jr, Fred E; Capps, Gregory L; Cooper, Reynold J; Radford, David C; Varner Jr, Robert L; Wilkerson, John F; Yu, Chang-Hong; Back, H.O.; Leviner, L.; Young, A.R.; Back , H.O.; Bai, X.; Hong, H.; Howard, S.; Medlin, D.; Sobolev, V.; Barabash, A.S.; Konovalov, S.I.; Vanyushin, I.; Yumatov, V.; Barbeau, P.S.; Collar, J.I.; Fields, N.; Boswell , M.; Brudanin, V.; Egorov, V.; Gusey, K.; Kochetov, O.; Shirchenko, M.; Timkin, V.; Yakushev, E.; Bugg, W.; Efremenko, M.; Burritt , T.H.; Burritt , T.H.; Busch, M.; Esterline, J.; Swift, G.; Tornow, W.; Hazama, R.; Nomachi, M.; Shima, T.; Finnerty , P.; et al.

    2011-01-01

    The Majorana Collaboration is assembling an array of HPGe detectors to search for neutrinoless double-beta decay in {sup 76}Ge. Initially, Majorana aims to construct a prototype module to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module are presented.

  1. Experiment Profile: Mu2e

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    alternatives and a cost range for the experiment, is expected in 2011. Earliest construction could begin 2013 with data-taking beginning in 2017. LIFESPAN OF EXPERIMENT: Two...

  2. The LUX experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Bradley, A.; Byram, D.; Cahn, S. B.; et al

    2015-03-24

    We present the status and prospects of the LUX experiment, which employs approximately 300 kg of two-phase xenon to search for WIMP dark matter interactions. The LUX detector was commissioned at the surface laboratory of the Sanford Underground Research Facility in Lead, SD, between December 2011 and February 2012 and the detector has been operating underground since January, 2013. These proceedings review the results of the commissioning run as well as the status of underground data-taking.

  3. Experiments in Steer Feeding. 

    E-Print Network [OSTI]

    Craig, John A. (John Alexander); Marshall, F. R. (Frederick Rupert)

    1904-01-01

    as to the relative value of these two very characteristic rations for steer feeding. Cotton? seed meal and hulls is the ration that is most generally used throughout the cotton belt, while corn and alfalfa will likely be conceded to be the ration which is most... STATIONS. BULLETIN NO. 76. Animal Husbandry Section. T E X A S G R S I C 1904. EXPERIMENTS IN STEER FEEDING I. RICE BY-PRODUCTS FOR STEER FEEDING. II. FODDERS FOR FEEDING STEERS WITH COTTONSEED MEAL. III. MOLASSES FOR STEER FEEDING. IV. COMPARISON...

  4. BooNE Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O OLaura|BilayerBiomimetic DyeBlue Gene/QENT2.0.01Experiment

  5. Experiment Safety Requirements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES OctoberEvan Racah Evan RacahNFTS-13Report InstructionsExperiment

  6. Fermilab | Tevatron | Experiments

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES OctoberEvan Racah861MayArtQuestions for theare thereExperiments

  7. Experiment Safety Requirements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you not find whatGas SeparationsRelevantTechnologiesEventsExperiment

  8. Experiment Safety Requirements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansasCommunitiesof Energy8) WignerEnergyAbout UsExpectationsExperiment

  9. Experiment Safety Requirements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansasCommunitiesof Energy8) WignerEnergyAboutExperiment Safety

  10. Sandia Energy - Experiments

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) byMultidayAlumniProjectsCyberNotLEDPhase FieldEnergyExperiments Home

  11. Stirling machine operating experience

    SciTech Connect (OSTI)

    Ross, B.; Dudenhoefer, J.E.

    1994-09-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that stirling machines are capable of reliable and lengthy operating lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and are not expected to operate for lengthy periods of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered. The record in this paper is not complete, due to the reluctance of some organizations to release operational data and because several organizations were not contacted. The authors intend to repeat this assessment in three years, hoping for even greater participation.

  12. Construction completed, PPPL is set to resume world-class fusion...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Experiment-Upgrade. Gallery: Technicians inspect the new center stack that forms the heart of the NSTX-U. (Photo by PPPL) Technicians inspect the new center stack that forms the...

  13. Experience Report for WOPR

    SciTech Connect (OSTI)

    Pope, G

    2010-04-06

    One of the purposes of the SQA effort at LLNL is to attempt to determine the 'goodness' of the research codes used for various scientific applications. Typically these are two and three dimensional multi-physics simulation and modeling codes. These legacy research codes are used for applciations such as atmospheric dispersion modeling and analysis and prediction of the performance of engineered systems. These codes are continually subjected to automated regression test suites consisting of verified and validated expected results. Code is managed in repositories. Experience level of developers is high in the knowledge domain, platforms, and languages used. Code size of the multi-physics code used in this study was 578,242 lines excluding comment and blank lines or 5538.7 function points. Languages were 70% C++, 20% C, and 10% Fortran. The code has 130 users and a development team of 14 and an embedded SQE. The code has achieved 100% prime feature test coverage, 73.6% functional test coverage, and 71.5% statement test coverage. The average cyclomatic complexity of the code was 6.25. The codes have evolved over 10 years. Research codes are challenging because there is a desire to balance agility with discipline as well as compliance with DOE standards. Agility is important to allow experimentation with new algorithms and addition of the latest physics features. Discipline is important to increase the quality of the codes. Automation of processes and defect prevention/detection are deployed throughout the software development process. Since resarch codes are a small segment of the software industry, not much information exists in terms of reliability studies on these types of codes. This paper describes attempts to determine the goodness of these research codes. Goodness defined as both correctness of the codes and their fault densities. Correctness is determined by user interviews, peer review; feature based automated testing, and coverage measurement. This paper focuses on the fault density aspect of goodness and reliability of the codes in particular. The approach taken was to use multiple fault density prediction methods and compare results to actual experimentation and other industry studies on fault density. As a result of the predictions and experiments our confidence in the prediction methods was increased and our confidence in the goodness of the code from a fault density perspective was given more context. A large unintended benefit of these experiments was to find defects hidden for years in the codes when using the Monte Carlo reliability testing results to develop heuristic based bug driven tests.

  14. The polarized SRF gun experiment

    SciTech Connect (OSTI)

    Kewisch,J.; Ben-Zvi, I.; Rao, T.; Burrill, A.; Pate, D.; Todd, R.; Wang, E.; Bluem, H.; Holmes, D.; Shultheiss, T.

    2008-10-01

    An experiment is under way to prove the feasibility of a super-conducting RF gun for the production of polarized electrons. We report on the progress of the experiment and on simulations predicting the possibility of success.

  15. Experience with capture cavity II

    SciTech Connect (OSTI)

    Koeth, T.; /Fermilab /Rutgers U., Piscataway; Branlard, J.; Edwards, H.; Fliller, R.; Harms, E.; Hocker, A.; McGee, M.; Pischalnikov, Y.; Prieto, P.; Reid, J.; /Fermilab

    2007-06-01

    Valuable experience in operating and maintaining superconducting RF cavities in a horizontal test module has been gained with Capture Cavity II. We report on all facets of our experience to date.

  16. The CAPTAIN Experiment

    E-Print Network [OSTI]

    Bian, Jianming

    2015-01-01

    The Cryogenic Apparatus for Precision Tests of Argon Interactions with Neutrinos (CAPTAIN) program is designed to make measurements of scientific importance to long-baseline neutrino physics and physics topics that will be explored by large underground detectors. The experiment employs two liquid Argon time projection chambers (LArTPCs), a primary detector with a mass of approximately 10 ton that will be deployed at different facilities for physics measurements and a two ton prototype detector for configuration testing. The physics programs for CAPTAIN include measuring neutron interactions at the Los Alamos Neutron Science Center, measuring neutrino interactions in the high-energy regime (1.5-5 GeV) at Fermilab NuMI beam, and measuring neutrino interactions in the low-energy regime (UV laser track has been seen in its TPC. This paper gives an overview of the CAPTAIN pr...

  17. The PANTHER User Experience

    SciTech Connect (OSTI)

    Coram, Jamie L.; Morrow, James D.; Perkins, David Nikolaus

    2015-09-01

    This document describes the PANTHER R&D Application, a proof-of-concept user interface application developed under the PANTHER Grand Challenge LDRD. The purpose of the application is to explore interaction models for graph analytics, drive algorithmic improvements from an end-user point of view, and support demonstration of PANTHER technologies to potential customers. The R&D Application implements a graph-centric interaction model that exposes analysts to the algorithms contained within the GeoGraphy graph analytics library. Users define geospatial-temporal semantic graph queries by constructing search templates based on nodes, edges, and the constraints among them. Users then analyze the results of the queries using both geo-spatial and temporal visualizations. Development of this application has made user experience an explicit driver for project and algorithmic level decisions that will affect how analysts one day make use of PANTHER technologies.

  18. Understanding Human Experience Henry Kautz

    E-Print Network [OSTI]

    Kautz, Henry

    Understanding Human Experience Henry Kautz One of the earliest goals of research in artificial intelligence was to create systems that can interpret and understand day to day human experience. Early work on the goal of building systems that understand human experience. Each of the previous barriers is weakened

  19. Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 2001

    SciTech Connect (OSTI)

    Virginia L. Finley

    2004-04-07

    The purpose of this report is to provide the U.S. Department of Energy (DOE) and the public with information on the level of radioactive and nonradioactive pollutants (if any) that are added to the environment as a result of the Princeton Plasma Physics Laboratory's (PPPL) operations. The results of the 2001 environmental surveillance and monitoring program for PPPL are presented and discussed. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 2001. PPPL has engaged in fusion energy research since 1951. The vision of the Laboratory is to create innovations to make fusion power a practical reality--a clean, alternative energy source. The Year 2001 marked the third year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion reactors. In 2001, PPPL's radiological environmental monitoring program measured tritium in the air at on- and off-site sampling stations. PPPL is capable of detecting small changes in the ambient levels of tritium by using highly sensitive monitors. The operation of an in-stack monitor located on D-site is a requirement of the National Emission Standard for Hazardous Air Pollutants (NESHAPs) regulations; also included in PPPL's radiological environmental monitoring program, are water monitoring--precipitation, ground-, surface-, and waste-waters. PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the D-site stack; the data are presented in this report. Groundwater monitoring continue d under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the low levels of volatile organic compounds in an area adjacent to PPPL. In 2001, PPPL was in compliance with its permit limits for surface and sanitary discharges and had no reportable releases. Additionally, as part of DOE's program for the purchase of recycled content and other environmentally preferred products, PPPL has ranked in the excellent category of 80 to 90% of the goal.

  20. Coupled-channel scattering on a torus

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Guo, Peng; Dudek, Jozef Jon; Edwards, Robert G.; Szczepaniak, Adam Pawel

    2013-07-01

    Based on the Hamiltonian formalism approach, a generalized Luscher's formula for two particle scattering in both the elastic and coupled-channel cases in moving frames is derived from a relativistic Lippmann-Schwinger equation. Some strategies for extracting scattering amplitudes for a coupled-channel system from the discrete finite-volume spectrum are discussed and illustrated with a toy model of two-channel resonant scattering. This formalism will, in the near future, be used to extract information about hadron scattering from lattice QCD computations.

  1. Zone routing in a torus network

    DOE Patents [OSTI]

    Chen, Dong; Heidelberger, Philip; Kumar, Sameer

    2013-01-29

    A system for routing data in a network comprising a network logic device at a sending node for determining a path between the sending node and a receiving node, wherein the network logic device sets one or more selection bits and one or more hint bits within the data packet, a control register for storing one or more masks, wherein the network logic device uses the one or more selection bits to select a mask from the control register and the network logic device applies the selected mask to the hint bits to restrict routing of the data packet to one or more routing directions for the data packet within the network and selects one of the restricted routing directions from the one or more routing directions and sends the data packet along a link in the selected routing direction toward the receiving node.

  2. Review Closeout for the National Spherical Torus

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Barry Sullivan, DOE/SC Tony Indelicato, DOE/PSO Maria Dikeakos, DOE/PSO #12;OFFICE OF SCIENCE 3 Charge

  3. The CAPTAIN Experiment

    E-Print Network [OSTI]

    Jianming Bian

    2015-09-25

    The Cryogenic Apparatus for Precision Tests of Argon Interactions with Neutrinos (CAPTAIN) program is designed to make measurements of scientific importance to long-baseline neutrino physics and physics topics that will be explored by large underground detectors. The experiment employs two liquid Argon time projection chambers (LArTPCs), a primary detector with a mass of approximately 10 ton that will be deployed at different facilities for physics measurements and a two ton prototype detector for configuration testing. The physics programs for CAPTAIN include measuring neutron interactions at the Los Alamos Neutron Science Center, measuring neutrino interactions in the high-energy regime (1.5-5 GeV) at Fermilab NuMI beam, and measuring neutrino interactions in the low-energy regime (UV laser track has been seen in its TPC. This paper gives an overview of the CAPTAIN program and reports the status of the commissioning. The up-to-date detector design and running plans are also described.

  4. Early strong interaction counter experiments

    SciTech Connect (OSTI)

    Terwilliger, K.M.

    1980-06-01

    The 17 /sup 0/ beam and some ..pi..-p two body scattering experiments run in the beginning years of the ZGS are discussed. (AIP)

  5. CHEM333: Experiment 2: Extraction

    E-Print Network [OSTI]

    Taber, Douglass

    CHEM­333: Experiment 2: Extraction: Prelab Assignment: Read chapter 4. In this lab you will perform an extraction (Chapter 4; Experiment B). Extraction is one of the easiest purification methods in the organic are insoluble in neutral/acidic water but are soluble in basic water. Follow the protocol and make sure that you

  6. Classes -10 Paid Experience -37

    E-Print Network [OSTI]

    Plotkin, Joshua B.

    , Philadelphia, PA Memorial Sloan Kettering Cancer Center, Pediatric Oncology, Nurse Extern (CAP), New York, NY 2011 and May 2012 in the School of Nursing to gather information about their summer work experiences Employment Summary Paid and Unpaid Experience, by Industry University of Pennsylvania School of Nursing

  7. A simple hidden variable experiment

    E-Print Network [OSTI]

    Arnold Neumaier

    2007-06-22

    An experiment is described which proves, using single photons only, that the standard hidden variables assumptions (commonly used to derive Bell inequalities) are inconsistent with quantum mechanics. The analysis is very simple and transparent. In particular, it demonstrates that a classical wave model for quantum mechanics is not ruled out by experiments demonstrating the violation of the traditional hidden variable assumptions.

  8. Experiments + Simulations = Better Nuclear Power Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Experiments + Simulations Better Nuclear Power Research Experiments Simulations Better Nuclear Power Research Atomic Level Simulations Enhance Characterization of Radiation...

  9. User Experiment Time-Line

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    User Experiment Time-Line Event Target Call for proposal 2 months before proposals are due PAC Proposals Due 7 weeks before PAC meeting TAC Report for PAC Proposals (includes...

  10. Essays in macroeconomics and experiments

    E-Print Network [OSTI]

    Shurchkov, Olga

    2008-01-01

    This dissertation consists of four chapters on empirical and experimental macroeconomics and other experimental topics. Chapter 1 uses a laboratory experiment to test the predictions of a dynamic global game designed to ...

  11. Progress in Compact Toroid Experiments

    SciTech Connect (OSTI)

    Dolan, Thomas James

    2002-09-01

    The term "compact toroids" as used here means spherical tokamaks, spheromaks, and field reversed configurations, but not reversed field pinches. There are about 17 compact toroid experiments under construction or operating, with approximate parameters listed in Table 1.

  12. Translating deixis: A subjective experience 

    E-Print Network [OSTI]

    Semlali, Hicham

    2007-01-01

    This thesis describes some of the conscious cognitive processes that are inherent in equivalence formation commencing from the transfer of deixis and culminating in the experience of source-to-target and target-to-source ...

  13. Perceptual Experience and Its Contents 

    E-Print Network [OSTI]

    Toribio, Josefa

    2002-01-01

    The contents of perceptual experience, it has been argued, often include a characteristic “non-conceptual” component (Evans, 1982). Rejecting such views, McDowell (1994) claims that such contents are conceptual in ...

  14. DOE Corporate Operating Experience Program

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2011-04-08

    The Order institutes a DOE wide program for the management of operating experience to prevent adverse operating incidents and facilitate the sharing of good work practices among DOE sites. Supersedes DOE O 210.2.

  15. User Experience Research and Statistics

    Broader source: Energy.gov [DOE]

    To improve your website or application, especially for new projects, EERE strongly recommends, but does not require, conducting user experience (UX) research. We only require that you get the...

  16. User Experience Research Online Tools

    Broader source: Energy.gov [DOE]

    The Office of Energy Efficiency and Renewable Energy (EERE) has a variety of online tools to help you conduct user experience (UX) research. The following tools are free for use by staff and contractors who work on the EERE website.

  17. The MINERvA Experiment

    SciTech Connect (OSTI)

    Harris, Deborah A.; Kopp, Sacha; /Fermilab

    2011-03-18

    The MINERvA experiment is a dedicated cross-section experiment whose aim is to measure neutrino cross sections for inclusive and exclusive final states on several nuclei. The detector is fully commissioned and began running in March 2010. As a dedicated cross-section experiment, MINERvA has a particular need to know the incident neutrino flux: both the absolute level and the energy dependence. In these proceedings we describe the MINERvA detector, give an update on the experimental status, and discuss the means to determine the neutrino flux. The MINERvA experiment is now running and has completed 25% of its full Low Energy run. There are various techniques planned for understanding the flux, including taking neutrino data at several different beam configurations. The experiment has gotten a first glimpse of two of the six configurations, and completed four horn current scans. Because of its exclusive final state reconstruction capabilities MINERvA can provide the much needed input for current and future oscillation experiments. The inclusive final state measurements and comparisons of nuclear effects across as many states as possible will provide new insights into neutrino-nucleus scattering.

  18. Basic Physics in the Levitated Dipole Experiment J. Kesner, L. Bromberg

    E-Print Network [OSTI]

    and Galileo spacecraft. > 1 fueled by solar wind and by Io volcanism. Io plasma torus is example of "pellet plasma is a challenge. Tends to have low power density at first wall. #12;Is BT necessary for toroidal 1) 1 p NC effects particles trapped

  19. Retail Choice Experiments: Comparing Early-AdopterExperience

    SciTech Connect (OSTI)

    Golove, William

    2003-03-01

    This paper reviews the experience with retail choice of non-residential electricity customers during the period from early 1998 through the first few months of 2000. Key findings include: (1) customers in California received a significantly smaller discount from utility tariffs than customers in other competitive markets; (2) this sample of large commercial/industrial customers believed they were benefiting significantly more from commodity savings from contracts with retail electricity service providers (RESP) than from value-added services; and,(3) market rules appear to be critical to customer experiences with retail competition, yet the relationship between market rules and market development is inadequately understood.

  20. Experiences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES OctoberEvan Racah Evan RacahNFTS-13

  1. Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansasCommunitiesof Energy8) WignerEnergyAbout UsExpectations of6

  2. NSTX Run Statistics and Update Friday November 16, 2001

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    Analyzer (Energetic Neutrals) EN X Fast Camera FC X PC - Video Only Fast H-Alpha FH X IFLIP Interim Fast Gas Puff: imaging GP X plus Video GRITS: GRazing Incidence Time- resolved Spectrometer GR X original Probes (new) LP X EPICS CAMAC Micro Ion Gauge ( MIG) MI X Mirnov Magnetics MM X Electron Density

  3. NSTX-U PRINCETON PLASMA D-NSTXU-??-??-???

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    -U: Stan Kaye TFTR Caretaking Vacuum Computing Tritium Quality Assurance/Quality Control AC Power Management Division Water Neutral Beam (Heating Systems Branch of Electrical Engineering) Radiofrequency (Heating Systems Branch of Electrical Engineering) Diagnostics: Brent Stratton Environmental, Safety

  4. Objective Criteria for Assessing Safe NSTX-U Startup

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ) and Failure Modes and Effects Analysis (FMEA) reviews. SAD/FMEA Author and Activity described in the SAD? 1. Review SAD Chapter 3 and associated FMEAs. Consider assessed? 2. Review SAD Chapter 3 and associated FMEAs, and review SAD Chapter

  5. Computer Engineer (NSTX-U) | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    support of daily experimental operations. The job entails a 4060 split of hardware and software engineering. Hardware activities employ a variety of CAD packages for chassis and...

  6. Objective Criteria for Assessing Safe NSTX-U Startup

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ) and Failure Modes and Effects Analysis (FMEA) reviews. SAD/FMEA Author and Activity Certification Committee-U facility and systems adequately described in the SAD? 1. Review SAD Chapter 3 and associated FMEAs FMEAs, and review SAD Chapter 4. Consider follow up interviews with cognizant systems engineers, SAD

  7. NSTX Centerstack Ancillary Systems Princeton Plasma Physics Laboratory

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    ASIPP CIEMAT FOM Inst DIFFER ENEA, Frascati CEA, Cadarache IPP, Jülich IPP, Garching ASCR, Czech Rep

  8. NSTX Upgrade: ST research to accelerate fusion development

    E-Print Network [OSTI]

    Inst for Nucl Res, Kiev Ioffe Inst TRINITI Chonbuk Natl U NFRI KAIST POSTECH Seoul Natl U ASIPP CIEMAT

  9. 71-960618-CLN-01 TO: NSTX WBS MANAGERS

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    the spreadsheet, double click on it from within MS Word. Then Excel will be started. Use "Save As" command

  10. Associate Research Physicist (Post Doc, Experimental Research, NSTX-U,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and Biofuels

  11. NSTX-U Control System Upgrades | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines lightGeospatialDevelopment of09 August

  12. NSTX-U: Builders and Users | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines lightGeospatialDevelopment of09 AugustPlasma Physics Lab Digital

  13. NSTX-U Press Kit | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you notHeatMaRIEdioxide capture CS SeminarsNREL Private Area

  14. Electronics Engineer (NSTX-U) | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas NuclearElectronic Structure and Magnetism inElectronicTechnique |

  15. From HumanFrom Human--Subject Experiments ToSubject Experiments To ComputationalComputational--Agent ExperimentsAgent Experiments

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    1 From HumanFrom Human--Subject Experiments ToSubject Experiments To Computational: ACE Electricity Market ACE Human-Subject (HS) Experiments Proof-of-Concept Proposal (GMUComputational--Agent ExperimentsAgent Experiments (And Everything In Between)(And Everything In Between) New Directions, IESA

  16. Neutrinoless Double Beta Decay Experiments

    E-Print Network [OSTI]

    Alberto Garfagnini

    2014-08-11

    Neutrinoless double beta decay is the only process known so far able to test the neutrino intrinsic nature: its experimental observation would imply that the lepton number is violated by two units and prove that neutrinos have a Majorana mass components, being their own anti-particle. While several experiments searching for such a rare decay have been performed in the past, a new generation of experiments using different isotopes and techniques have recently released their results or are taking data and will provide new limits, should no signal be observed, in the next few years to come. The present contribution reviews the latest public results on double beta decay searches and gives an overview on the expected sensitivities of the experiments in construction which will be able to set stronger limits in the near future.

  17. The Lead Radius Experiment PREX

    SciTech Connect (OSTI)

    Robert Michaels

    2006-10-02

    The proposed PREX experiment at Jefferson Lab will measure the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons at an energy of 850 MeV and a scattering angle of 6 degrees. Since the Z0 boson couples mainly to neutrons, this asymmetry provides a clean measurement of R{sub n} with a projected experimental precision of 1 %. In addition to being a fundamental test of nuclear theory, a precise measurement of R{sub n} pins down the density dependence of the symmetry energy of neutron rich nuclear matter which has impacts on neutron star structure, heavy ion collisions, and atomic parity violation experiments.

  18. Development of a low-energy and high-current pulsed neutral beam injector with a washer-gun plasma source for high-beta plasma experiments

    SciTech Connect (OSTI)

    Ii, Toru; Gi, Keii; Umezawa, Toshiyuki; Inomoto, Michiaki; Ono, Yasushi; Asai, Tomohiko

    2012-08-15

    We have developed a novel and economical neutral-beam injection system by employing a washer-gun plasma source. It provides a low-cost and maintenance-free ion beam, thus eliminating the need for the filaments and water-cooling systems employed conventionally. In our primary experiments, the washer gun produced a source plasma with an electron temperature of approximately 5 eV and an electron density of 5 Multiplication-Sign 10{sup 17} m{sup -3}, i.e., conditions suitable for ion-beam extraction. The dependence of the extracted beam current on the acceleration voltage is consistent with space-charge current limitation, because the observed current density is almost proportional to the 3/2 power of the acceleration voltage below approximately 8 kV. By optimizing plasma formation, we successfully achieved beam extraction of up to 40 A at 15 kV and a pulse length in excess of 0.25 ms. Its low-voltage and high-current pulsed-beam properties enable us to apply this high-power neutral beam injection into a high-beta compact torus plasma characterized by a low magnetic field.

  19. NSTX Upgrade Umbrella Arch and Foot Reinforcements, Local Dome Details 1 | P a g e NSTX Upgrade

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    clevis restraint/support. Calculation (Calculation is either documented here or attached) Attached was accomplished.) With recommended reinforcements, the 3/4 inch 316 bolts are acceptable for the upgrade loads in strength by integrating it with the TF strap support. Cognizant Engineer's printed name, signature

  20. FURTHERING THE RECLAIMED MATERIALS EXPERIENCE

    E-Print Network [OSTI]

    Bartels, Robert A.

    2012-08-31

    that would cover a broad spectrum of Design Management principles. Scope of Work: The topic is specifi cally related to the reclaimed materials industry and ways to improve the buyer's and seller's experience in relation to the location and sale of materials...

  1. University Housing! First Year Experience

    E-Print Network [OSTI]

    community -Committed faculty member for academic success -Group Work focused -Learning Community Assistant for academic success -Group Work focused -Learning Community Assistant (LCA) Living Learning Communities (LLCs) + + The choice is yours! First Year Experience Thematic First Year Student Housing focused around development

  2. Chaos Experiments at Microwave Frequencies

    E-Print Network [OSTI]

    Anlage, Steven

    Meeting 14 June, 2001 #12;Two Types of Experiments "Quantum Chaos" Basic study of wave dynamics knowledge of initial conditions p q > h/2 ( ) t iVqAi m =+-- 2 2 1 Manifestations of quantum chaos of a pc board Ray splitting Fields confined mainly in slab Image |Ez|2 under and around the slab Add loss

  3. The NOMAD Experiment at CERN

    E-Print Network [OSTI]

    Vannucci, F

    2014-01-01

    The purpose of this paper is to review the experimental apparatus and some physics results fromthe NOMAD(neutrino oscillation magnetic detector) experiment which took data in the CERN wide-band neutrino beam from 1995 to 1998. It collected and reconstructed more than one million charged current(CC)$\

  4. Study Abroad Study Abroad Experiences

    E-Print Network [OSTI]

    Gering, Jon C.

    of Science in Nursing (ABSN) Clinical Sites · Emphasis on community-based nursing practice · Adult programs Facilities · The Nursing Simulation Center (NSC) is housed in the Health Sciences Building, and serves as a starting place in the clinical learning experience for all nursing students. It is a training

  5. Inertial Confinement Fusion Experiments & Modeling

    E-Print Network [OSTI]

    Cohen, David

    Inertial Confinement Fusion Experiments & Modeling Using X-ray Absorption Spectroscopy of Thin Does Inertial Confinement Fusion (ICF) Work? A spherical capsule filled with fuel (deuterium Laboratory) #12;Outline I. What is Fusion? II. How does Inertial Fusion work? The physics of indirect

  6. MSRF Experience in Urologic Oncology

    E-Print Network [OSTI]

    Leistikow, Bruce N.

    ;Mentorship is Key! Availability and Commitment Shared Goals Track Record Good "Fit" #12;Types of Research is Urology? What is Urologic Oncology? #12;Why Medical Student Research Fellowship (MSRF)? Gain independent research experience Explore a career as a physician scientist Explore a particular specialty in-depth #12

  7. DOE Corporate Operating Experience Program

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-06-12

    The Order establishes a DOE wide program for management of operating experience to prevent adverse operating incidents and to expand the sharing of good work practices among DOE sites. Canceled by DOE O 210.2A. Does not cancel other directives.

  8. Soliton molecules: Experiments and optimization

    SciTech Connect (OSTI)

    Mitschke, Fedor

    2014-10-06

    Stable compound states of several fiber-optic solitons have recently been demonstrated. In the first experiment their shape was approximated, for want of a better description, by a sum of Gaussians. Here we discuss an optimization strategy which helps to find preferable shapes so that the generation of radiative background is reduced.

  9. Soudan 2 nucleon decay experiment

    SciTech Connect (OSTI)

    Thron, J.L.

    1986-01-01

    The Soudan 2 nucleon decay experiment consists of a 1.1 Kton fine grained iron tracking calorimeter. It has a very isotropic detection structure which along with its flexible trigger will allow detection of multiparticle and neutrino proton decay modes. The detector has now entered its construction stage.

  10. RELATIVISTIC HEAVY ION COLLISIONS: EXPERIMENT

    E-Print Network [OSTI]

    Friedlander, Erwin M.

    2010-01-01

    63, Sc 63, Gu 76, Go 77, Ka 80a] and thermodynamic [Me 80,by Meyer et al. [Me 80a],where the transverse momenta of thechamber experiment [ ~ a 80a] with 1.8 AGeV 4 0 ~ r incident

  11. Two LANL laboratory astrophysics experiments

    SciTech Connect (OSTI)

    Intrator, Thomas P.

    2014-01-24

    Two laboratory experiments are described that have been built at Los Alamos (LANL) to gain access to a wide range of fundamental plasma physics issues germane to astro, space, and fusion plasmas. The overarching theme is magnetized plasma dynamics which includes significant currents, MHD forces and instabilities, magnetic field creation and annihilation, sheared flows and shocks. The Relaxation Scaling Experiment (RSX) creates current sheets and flux ropes that exhibit fully 3D dynamics, and can kink, bounce, merge and reconnect, shred, and reform in complicated ways. Recent movies from a large data set describe the 3D magnetic structure of a driven and dissipative single flux rope that spontaneously self-saturates a kink instability. Examples of a coherent shear flow dynamo driven by colliding flux ropes will also be shown. The Magnetized Shock Experiment (MSX) uses Field reversed configuration (FRC) experimental hardware that forms and ejects FRCs at 150km/sec. This is sufficient to drive a collision less magnetized shock when stagnated into a mirror stopping field region with Alfven Mach number MA=3 so that super critical shocks can be studied. We are building a plasmoid accelerator to drive Mach numbers MA >> 3 to access solar wind and more exotic astrophysical regimes. Unique features of this experiment include access to parallel, oblique and perpendicular shocks, shock region much larger than ion gyro radii and ion inertial length, room for turbulence, and large magnetic and fluid Reynolds numbers.

  12. Organic Photovoltaics Experiments Showcase 'Superfacility' Concept

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Organic Photovoltaics Experiments Showcase 'Superfacility' Concept Organic Photovoltaics Experiments Showcase 'Superfacility' Concept Collaboration Key to Enabling On-The-Fly HPC...

  13. Operational experience of the OC-OTEC experiments at NELH

    SciTech Connect (OSTI)

    Link, H.

    1989-02-01

    The Solar Energy Research Institute, under funding and program direction from the US Department of Energy, has been operating a small-scale test apparatus to investigate key components of open- cycle ocean thermal energy conversion (OC-OTEC). The apparatus started operations in October 1987 and continues to provide valuable information on heat-and mass-transfer processes in evaporators and condensers, gas sorption processes as seawater is depressurized and repressurized, and control and instrumentation characteristics of open-cycle systems. Although other test facilities have been used to study some of these interactions, this is the largest apparatus of its kind to use seawater since Georges Claude`s efforts in 1926. The information obtained from experiments conducted in this apparatus is being used to design a larger scale experiment in which a positive net power production is expected to be demonstrated for the first time with OC-OTEC. This paper describes the apparatus, the major tests conducted during its first 18 months of operation, and the experience gained in OC-OTEC system operation. 13 refs., 8 figs.

  14. The DAMIC dark matter experiment

    E-Print Network [OSTI]

    Aguilar-Arevalo, A; Bertou, X; Bole, D; Butner, M; Cancelo, G; Vázquez, A Castañeda; Chavarria, A E; Neto, J R T de Mello; Dixon, S; D'Olivo, J C; Estrada, J; Moroni, G Fernandez; Torres, K P Hernández; Izraelevitch, F; Kavner, A; Kilminster, B; Lawson, I; Liao, J; López, M; Molina, J; Moreno-Granados, G; Pena, J; Privitera, P; Sarkis, Y; Scarpine, V; Schwarz, T; Haro, M Sofo; Tiffenberg, J; Machado, D Torres; Trillaud, F; You, X; Zhou, J

    2015-01-01

    The DAMIC (Dark Matter in CCDs) experiment uses high resistivity, scientific grade CCDs to search for dark matter. The CCD's low electronic noise allows an unprecedently low energy threshold of a few tens of eV that make it possible to detect silicon recoils resulting from interactions of low mass WIMPs. In addition the CCD's high spatial resolution and the excellent energy response results in very effective background identification techniques. The experiment has a unique sensitivity to dark matter particles with masses below 10 GeV/c$^2$. Previous results have demonstrated the potential of this technology, motivating the construction of DAMIC100, a 100 grams silicon target detector currently being installed at SNOLAB. In this contribution, the mode of operation and unique imaging capabilities of the CCDs, and how they may be exploited to characterize and suppress backgrounds will be discussed, as well as physics results after one year of data taking.

  15. Nodalization study for BETHSY experiment

    SciTech Connect (OSTI)

    Petelin, S.; Mavko, B.; Ravnikar, I. [Univ. of Ljubljana (Slovenia); Cebull, P.; Hassan, Y.A. [Texas A and M Univ., College Station, TX (United States). Dept. of Nuclear Engineering

    1996-08-01

    The BETHSY experiment 9.1.b was used to assess different versions of the RELAP5 computer code using three various detailed nodalizations. This experimental transient scenario involved a scaled 2 inch cold leg break without high pressure safety injection and with delayed operator action for a secondary system depressurization. In order to optimize details of nodalization regard to satisfactory accuracy a detailed study of different RELAP5 codes and nodalizations was performed. Qualitative evolution of RELAP5 code was also analyzed.

  16. Jitter debugging two laser experiments

    SciTech Connect (OSTI)

    Rayner, D.M.; Hackett, P.A.; Willis, C.

    1982-03-01

    A method to overcome the problem of timing jitter in two laser experiments is described. The technique involves the use of a time-to-pulse height converter to measure the interpulse separation and a data acquisition system capable of recording this and other experimental parameters on a shot-to-shot basis. The method is estimated to be useful in measurement systems with resolution down to 10 ps.

  17. Complete Experiments for Pion Photoproduction

    E-Print Network [OSTI]

    Lothar Tiator

    2012-11-16

    The possibilities of a model-independent partial wave analysis for pion, eta or kaon photoproduction are discussed in the context of complete experiments. It is shown that the helicity amplitudes obtained from at least 8 polarization observables including beam, target and recoil polarization can not be used to analyze nucleon resonances. However, a truncated partial wave analysis, which requires only 5 observables will be possible with minimal model assumptions.

  18. Plasma Wakefield Experiments at FACET

    SciTech Connect (OSTI)

    Hogan, M.J.; England, R.J.; Frederico, J.; Hast, C.; Li, S.Z.; Litos, M.; Walz, D.; /SLAC; An, W.; Clayton, C.E.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.; Tochitsky, S.; /UCLA; Muggli, P.; Pinkerton, S.; Shi, Y.; /Southern California U.

    2011-08-19

    FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration beginning in summer 2011. The nominal FACET parameters are 23GeV, 3nC electron bunches compressed to {approx}20{micro}m long and focused to {approx}10{micro}m wide. The intense fields of the FACET bunches will be used to field ionize neutral lithium or cesium vapor produced in a heat pipe oven. Previous experiments at the SLAC FFTB facility demonstrated 50GeV/m gradients in an 85cm field ionized lithium plasma where the interaction distance was limited by head erosion. Simulations indicate the lower ionization potential of cesium will decrease the rate of head erosion and increase single stage performance. The initial experimental program will compare the performance of lithium and cesium plasma sources with single and double bunches. Later experiments will investigate improved performance with a pre-ionized cesium plasma. The status of the experiments and expected performance are reviewed. The FACET Facility is being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration. The facility will begin commissioning in summer 2011 and conduct an experimental program over the coming five years to study electron and positron beam driven plasma acceleration with strong wake loading in the non-linear regime. The FACET experiments aim to demonstrate high-gradient acceleration of electron and positron beams with high efficiency and negligible emittance growth.

  19. Final Report: Levitated Dipole Experiment

    SciTech Connect (OSTI)

    Kesner, Jay [Massachusetts Institute of Technology; Mauel, Michael [Columbia University

    2013-03-10

    Since the very first experiments with the LDX, research progress was rapid and significant. Initial experiments were conducted with the high-field superconducting coil suspended by three thin rods. These experiments produced long-pulse, quasi-steady-state microwave discharges, lasting more than 10 s, having peak beta values of 20% [Garnier et al., Physics of Plasmas, 13 (2006) 056111]. High- beta, near steady-state discharges have been maintained in LDX for more than 20 seconds, and this capability made LDX the longest pulse fusion confinement experiment operating in the U.S. fusion program. A significant measure of progress in the LDX research program was the routine investigation of plasma confinement with a magnetically-levitated dipole and the resulting observations of confinement improvement. In both supported and levitated configurations, detailed measurements were made of discharge evolution, plasma dynamics and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. High-temperature plasma was created by multi frequency electron cyclotron resonance heating at 2.45 GHz, 6.4 GHz, 10.5 GHz and 28 GHz allowing control of heating profiles. Depending upon neutral fueling rates, the LDX discharges contain a fraction of energetic electrons, with mean energies above 50 keV. Depending on whether or not the superconducting dipole was levitated or supported, the peak thermal electron temperature was estimated to exceed 500 eV and peak densities to approach 1e18 m?3. We have found that levitation causes a strong inwards density pinch [Boxer et al., Nature Physics, 6 (2010) 207] and we have observed the central plasma density increase dramatically indicating a significant improvement in the confinement of a thermal plasma species.

  20. From HumanFrom Human--Subject Experiments ToSubject Experiments To ComputationalComputational--Agent ExperimentsAgent Experiments

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    1 From HumanFrom Human--Subject Experiments ToSubject Experiments To Computational Experiments - 100% human 100% computational agents What is Agent-based Comp Econ (ACE)? - 100% computational://www.econ.iastate.edu/tesfatsi/aexper.htm #12;3 Spectrum of Possible Experiments 100% human Humans with computer access Human

  1. My PhD Experience Rosta Farzan

    E-Print Network [OSTI]

    Brusilovsky, Peter

    10/25/09 1 My PhD Experience Rosta Farzan (rfarzan@cs.cmu.edu) Oct 19, 2009 My PhD Experience... #12;10/25/09 2 My PhD Experience... SharifUniversityofTechnology Bachelor'sofScienceinComputerEngineering My PhD Experience... So;wareengineer@aso;warecompany Ebusinesssystemsfordialoguesbetweenpeers #12

  2. Unuploaded experiments have no result

    E-Print Network [OSTI]

    Andrei Khrennikov

    2015-05-16

    The aim of this note is to attract once again attention of the quantum community to statistical analysis of data which was reported as violating Bell's inequality. This analysis suffers of a number of problems. And the main problem is that rough data is practically unavailable. This situation differs crucially from the situation in other domains of experimental research, for example, from molecular biology and genetics. Thus the first message of this note is that this situation is really unacceptable. Experiments which are not followed by the open access to the rough data have to be considered as with no result. The absence of rough data generates a variety of problems in statistical interpretation of the results of Bell's type experiment. Among them I mention the following four problems: a) statistical justification of no-signaling, b) "Aspect's anomalies", c) the time window problem (coincidence loophole), d) general statistical analysis of Bell's experiment. May be this note would stimulate others to contribute to analysis of these problems as well as to create the open access data-base on Bell tests and other tests on quantum foundations.

  3. Small-Scale Experiments.10-gallon drum experiment summary

    SciTech Connect (OSTI)

    Rosenberg, David M.

    2015-02-05

    A series of sub-scale (10-gallon) drum experiments were conducted to characterize the reactivity, heat generation, and gas generation of mixtures of chemicals believed to be present in the drum (68660) known to have breached in association with the radiation release event at the Waste Isolation Pilot Plant (WIPP) on February 14, 2014, at a scale expected to be large enough to replicate the environment in that drum but small enough to be practical, safe, and cost effective. These tests were not intended to replicate all the properties of drum 68660 or the event that led to its breach, or to validate a particular hypothesis of the release event. They were intended to observe, in a controlled environment and with suitable diagnostics, the behavior of simple mixtures of chemicals in order to determine if they could support reactivity that could result in ignition or if some other ingredient or event would be necessary. There is a significant amount of uncertainty into the exact composition of the barrel; a limited sub-set of known components was identified, reviewed with Technical Assessment Team (TAT) members, and used in these tests. This set of experiments was intended to provide a framework to postulate realistic, data-supported hypotheses for processes that occur in a “68660-like” configuration, not definitively prove what actually occurred in 68660.

  4. INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTH CAROLINA

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01

    OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTHOF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTHdata from a hydraulic fracturing experiment have been

  5. Coherent electron cooling demonstration experiment

    SciTech Connect (OSTI)

    Litvinenko, V.N.; Belomestnykh, S.; Ben-Zvi, I.; Brutus, J.C.; Fedotov, A.; Hao, Y.; Kayran, D.; Mahler, G.; Marusic, A.; Meng, W.; McIntyre, G.; Minty, M.; Ptitsyn, V.; Pinayev, I.; Rao, T.; Roser, T.; Sheehy, B.; Tepikian, S.; Than, R.; Trbojevic, D.; Tuozzolo, J.; Wang, G.; Yakimenko, V.; Hutton, A.; Krafft, G.; Poelker, M.; Rimmer, R.; Bruhwiler, D.; Abell, D.T.; Nieter, C.; Ranjbar, V.; Schwartz, B.; Kholopov M.; Shevchenko, O.; McIntosh, P.; Wheelhouse, A.

    2011-09-04

    Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron-hadron and electron-hadron colliders. In a CEC system, a hadron beam interacts with a cooling electron beam. A perturbation of the electron density caused by ions is amplified and fed back to the ions to reduce the energy spread and the emittance of the ion beam. To demonstrate the feasibility of CEC we propose a proof-of-principle experiment at RHIC using SRF linac. In this paper, we describe the setup for CeC installed into one of RHIC's interaction regions. We present results of analytical estimates and results of initial simulations of cooling a gold-ion beam at 40 GeV/u energy via CeC. We plan to complete the program in five years. During first two years we will build coherent electron cooler in IP2 of RHIC. In parallel we will develop complete package of computer simulation tools for the start-to-end simulation predicting exact performance of a CeC. The later activity will be the core of Tech X involvement into the project. We will use these tools to predict the performance of our CeC device. The experimental demonstration of the CeC will be undertaken in years three to five of the project. The goal of this experiment is to demonstrate the cooling of ion beam and to compare its measured performance with predictions made by us prior to the experiments.

  6. Physics with the ALICE experiment

    SciTech Connect (OSTI)

    Kharlov, Yu. V. [Institute for High Energy Physics (Russian Federation)

    2013-12-15

    ALICE experiment at LHC collects data in pp collisions at 1497-1 = 0.9, 2.76, and 7 TeV and in PbPb collisions at 2.76 TeV. Highlights of the detector performance and an overview of experimental results measured with ALICE in pp and AA collisions are presented in this paper. Physics with protonproton collisions is focused on hadron spectroscopy at low and moderate p{sub t}. Measurements with lead-lead collisions are shown in comparison with those in pp collisions, and the properties of hot quark matter are discussed.

  7. Status of the AMS Experiment

    E-Print Network [OSTI]

    Kounine, A

    2010-01-01

    Alpha Magnetic Spectrometer (AMS-02) is a general purpose high energy particle detector which will be deployed on the International Space Station (ISS) at the end of 2010 - beginning of 2011 to conduct a unique 10 to 18 year mission of fundamental physics research in space. Among the physics objectives of AMS are a search for an understanding of Dark Matter, Antimatter, the origin of cosmic rays and the exploration of new physics phenomena not possible to study from ground based experiments. This article reviews the status of the AMS-02 detector construction, detector calibration results as well as AMS physics potential for new phenomena searches.

  8. A Class Experiment in Imagery

    E-Print Network [OSTI]

    Hanger, James Howard

    1911-01-01

    '. Various arguments we~>e introduced as evidence. This is a good example*-"Wot all my motor tendencies depend upon past motor experiences. It is possible for me to imagine' myself falling through space from an airship or any high point. I have never... when looking for the first time from a considerable height is,no doubt,the basis for his imagined feeling in connedtion with the thought^of falling from an airship. But in this sensation, it is safe to say that the rush of air as one approaches...

  9. Physics with the ALICE experiment

    E-Print Network [OSTI]

    Yuri Kharlov; for the ALICE collaboration

    2012-03-09

    ALICE experiment at LHC collects data in pp collisions at $\\sqrt{s}$=0.9, 2.76 and 7 TeV and in PbPb collisions at 2.76 TeV. Highlights of the detector performance and an overview of experimental results measured with ALICE in pp and AA collisions are presented in this paper. Physics with proton-proton collisions is focused on hadron spectroscopy at low and moderate $p_T$. Measurements with lead-lead collisions are shown in comparison with those in pp collisions, and the properties of hot quark matter are discussed.

  10. RF breakdown experiments at SLAC

    SciTech Connect (OSTI)

    Laurent, L. [University of California Davis, Davis, California 95616 (United States); Vlieks, A.; Pearson, C.; Caryotakis, G.; Luhmann, N.C. [Stanford Linear Accelerator Center, Menlo Park, California 94025 (United States)

    1999-05-01

    RF breakdown is a critical issue in the conditioning of klystrons, accelerator sections, and rf components for the next linear collider (NLC), as well as other high gradient accelerators and high power microwave sources. SLAC is conducting a series of experiments using an X-band traveling wave ring to characterize the processes and trigger mechanisms associated with rf breakdown. The goal of the research is to identify materials, processes, and manufacturing methods that will increase the breakdown threshold and minimize the time required for conditioning. {copyright} {ital 1999 American Institute of Physics.}

  11. Neutrinoless double beta decay experiments

    E-Print Network [OSTI]

    K. Zuber

    2006-10-04

    The study of neutrinoless double beta decay is of outmost importance for neutrino physics. It is considered to be the gold plated channel to probe the fundamental character of neutrinos and to determine the neutrino mass. From the experimental point about nine different isotopes are explored for the search. After a general introduction follows a short discussion on nuclear matrix element calculations and supportive measurements. The current experimental status of double beta searches is presented followed by a short discussion of the ideas and proposals for large scale experiments.

  12. ISOTHERMAL AIR INGRESS VALIDATION EXPERIMENTS

    SciTech Connect (OSTI)

    Chang H Oh; Eung S Kim

    2011-09-01

    Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic’s Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident.

  13. The polarized SRF gun experiment.

    SciTech Connect (OSTI)

    Kewisch,J.; Ben-Zvi, I.; Rao, T.; Burrill, A.; Pate, D.; Grover, R.; Todd, R.; Bluem, H.; Holmes, D.; Schultheiss, T.

    2007-09-10

    RF electron guns are capable of producing electron bunches with high brightness, which outperform DC electron guns and may even be able to provide electron beams for the ILC without the need for a damping ring. However, all successful existing guns for polarized electrons are DC guns because the environment inside an RF gun is hostile to the GaAs cathode material necessary for polarization. While the typical vacuum pressure in a DC gun is better than 10{sup -11} torr the vacuum in an RF gun is in the order of 10{sup -9} torr. Experiments at BINP Novosibirsk show that this leads to strong ion back-bombardment and generation of dark currents, which destroy the GaAs cathode in a short time. The situation might be much more favorable in a (super-conducting) SRF gun. The cryogenic pumping of the gun cavity walls may make it possible to maintain a vacuum close to 10{sup -12} torr, solving the problem of ion bombardment and dark currents. Of concern would be contamination of the gun cavity by evaporating cathode material. This report describes an experiment that Brookhaven National Laboratory (BNL) in collaboration with Advanced Energy Systems (AES) is conducting to answer these questions.

  14. Sasol's Fischer-Tropsch experience

    SciTech Connect (OSTI)

    Dry, M.E.

    1982-08-01

    Product slate from Fischer-Tropsch processing can be selectively varied over a wide range. Depending on the type reactor chosen and conditions of operation, either gasoline or diesel components can amount to as much as 75% of the hydrocarbons produced. Based on over 26 years of commercial experience in Fischer-Tropsch operations, Sasol has identified factors for controlling the product slate with respect to fraction produced and yields. Experience with two reactor types demonstrates their advantages and limitations while manipulation of the operating conditions has established control techniques for yields. Reactors of the low temperature fixed bed type produce products that are paraffinic and largely wax while yields from operation of higher temperature fluidized catalyst are a product that is highly olefinic and falls in the gasoline boiling range. After work up using normal refinery processing, the final products meet specifications applicable for motor fuels that are entirely compatible with crude oil products. In fact, the diesel product is superior because it has a cetane number higher than normal and a lower ring compound content.

  15. Experiment Design and Analysis Guide - Neutronics & Physics

    SciTech Connect (OSTI)

    Misti A Lillo

    2014-06-01

    The purpose of this guide is to provide a consistent, standardized approach to performing neutronics/physics analysis for experiments inserted into the Advanced Test Reactor (ATR). This document provides neutronics/physics analysis guidance to support experiment design and analysis needs for experiments irradiated in the ATR. This guide addresses neutronics/physics analysis in support of experiment design, experiment safety, and experiment program objectives and goals. The intent of this guide is to provide a standardized approach for performing typical neutronics/physics analyses. Deviation from this guide is allowed provided that neutronics/physics analysis details are properly documented in an analysis report.

  16. Final Report: Levitated Dipole Experiment

    SciTech Connect (OSTI)

    Kesner, Jay; Mauel, Michael

    2013-03-10

    Since the very first experiments with the LDX, research progress was rapid and significant. Initial experiments were conducted with the high-field superconducting coil suspended by three thin rods. These experiments produced long-pulse, quasi-steady-state microwave discharges, lasting more than 10 s, having peak beta values of 20% [Garnier, Phys. Plasmas, v13, p. 056111, 2006]. High-beta, near steady-state discharges have been maintained in LDX for more than 20 seconds, and this capability makes LDX the longest pulse fusion confinement experiment now operating in the U.S. fusion program. In both supported and levitated configurations, detailed measurements are made of discharge evolution, plasma dynamics and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. High-temperature plasma is created by multifrequency electron cyclotron resonance heating allowing control of heating profiles. Depending upon neutral fueling rates, the LDX discharges contain a fraction of energetic electrons, with mean energies above 50 keV. Depending on whether or not the superconducting dipole is levitated or supported, the peak thermal electron temperature is estimated to exceed 500 eV and peak densities reach 1.0E18 (1/m3). Several significant discoveries resulted from the routine investigation of plasma confinement with a magnetically-levitated dipole. For the first time, toroidal plasma with pressure approaching the pressure of the confining magnetic field was well-confined in steady-state without a toroidal magnetic field. Magnetic levitation proved to be reliable and is now routine. The dipole's cryostat allows up to three hours of "float time" between re-cooling with liquid helium and providing scientists unprecedented access to the physics of magnetizd plasma. Levitation eliminates field-aligned particle sources and sinks and results in a toroidal, magnetically-confined plasma where profiles are determined by cross-field transport. We find levitation causes the central plasma density to increase dramatically and to significantly improve the confinement of thermal plasma [Boxer, Nature-Physics, v8, p. 949, 2010]. Several diagnostic systems have been used to measure plasma fluctuations, and these appear to represent low-frequency convection that may lead to adiabatic heating and strongly peaked pressure profiles. These experiments are remarkable, and the motivate wide-ranging studies of plasma found in space and confined for fusion energy. In the following report, we describe: (i) observations of the centrally-peaked density profile that appears naturally as a consequence of a strong turbulent pinch, (ii) observations of overall density and pressure increases that suggest large improvements to the thermal electron confinement time result occur during levitation, and (iii) the remarkable properties of low-frequency plasma fluctuations that cause magnetized plasma to "self-organize" into well-confined, centrally-peaked profiles that are relative to fusion and to space.

  17. Hanbury Brown-Twiss Experiment with Coherent

    E-Print Network [OSTI]

    39 Chapter 2 Hanbury Brown-Twiss Experiment with Coherent Light This chapter was previously a theory that allows us #12;40 Hanbury Brown-Twiss Experiment with Coherent Light to construct processes

  18. Reflectometer Measurement for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Reflectometer Measurement for the Levitated Dipole Experiment The Levitated Dipole Experiment geometries Magnetic shear makes analysis more difficult (not a problem in LDX) Bandwidth competition propagation perpendicular to the magnetic field Solving: 1. Measure peak density in LDX The innermost

  19. New Physics Effects in Long Baseline Experiments

    E-Print Network [OSTI]

    Osamu Yasuda

    2007-10-13

    We discuss the implications of new physics, which modifies the matter effect in neutrino oscillations, to long baseline experiments, particularly the MINOS experiment. An analytic formula in the presence of such a new physics interaction is derived for $P(\

  20. Suspended sediment erosion in laboratory flume experiments

    E-Print Network [OSTI]

    Cornell, Katrina Muir

    2007-01-01

    Laboratory flume experiments are used to examine the role of suspended sediment abrasion in bedrock channel erosion. A range of topographies was used, from a planar bed to a sinuous and scalloped inner channel. Experiments ...

  1. Status of the MAJORANA DEMONSTRATOR experiment

    SciTech Connect (OSTI)

    Martin, R. D.; Abgrall, N.; Aguayo, Estanislao; Avignone, F. T.; Barabash, Alexander S.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Caldwell, A. S.; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Combs, Dustin C.; Detwiler, Jason A.; Doe, P. J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S.; Esterline, James H.; Fast, James E.; Finnerty, P.; Fraenkle, Florian; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M.; Gruszko, J.; Guiseppe, Vincente; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, R.; Hoppe, Eric W.; Howard, Stanley; Howe, M. A.; Keeter, K.; Kidd, M. F.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaFerriere, Brian D.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; MacMullin, J.; MacMullin, S.; Mertens, S.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; O'Shaughnessy, Mark D.; Overman, Nicole R.; Phillips, David; Poon, Alan; Pushkin, K.; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Romero-Romero, E.; Ronquest, M. C.; Schubert, Alexis G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Snyder, N.; Soin, Aleksandr; Suriano, Anne-Marie; Thompson, J.; Timkin, V.; Tornow, W.; Varner, R. L.; Vasilyev, Sergey; Vetter, Kai; Vorren, Kris R.; White, Brandon R.; Wilkerson, J. F.; Xu, W.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir

    2014-07-08

    The MAJORANA DEMONSTRATOR neutrinoless double beta-decay experiment is currently under construction at the Sanford Underground Research Facility in South Dakota, USA. An overview and status of the experiment are given.

  2. Status of the MAJORANA DEMONSTRATOR experiment

    SciTech Connect (OSTI)

    Martin, R. D. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA and Department of Physics, University of South Dakota, Vermillion, SD (United States); Abgrall, N.; Chan, Y-D.; Hegai, A.; Mertens, S.; Poon, A. W. P.; Vetter, K. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Aguayo, E.; Fast, J. E.; Hoppe, E. W.; Kouzes, R. T.; LaFerriere, B. D.; Orrell, J. L.; Overman, N. R.; Soin, A. [Pacific Northwest National Laboratory, Richland, WA (United States); Avignone III, F. T. [Department of Physics and Astronomy, University of South Carolina, Columbia, SC, USA and Oak Ridge National Laboratory, Oak Ridge, TN (United States); Barabash, A. S.; Konovalov, S. I.; Yumatov, V. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bertrand, F. E. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); and others

    2014-06-24

    The MAJORANA DEMONSTRATOR neutrinoless double beta-decay experiment is currently under construction at the Sanford Underground Research Facility in South Dakota, USA. An overview and status of the experiment are given.

  3. NNSA releases Stockpile Stewardship Program quarterly experiments...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in particular the first Pu experiment on NIF, the return to operations of the TA-55 gas gun, a successful series of plutonium experiments on Joint Actinide Shock Physics...

  4. Experiences of Women Leaders in México 

    E-Print Network [OSTI]

    Moreno, Ana

    2012-10-19

    This qualitative study sought to understand better the experiences of women leaders in México, a predominantly male-dominated culture. Seven women leaders were interviewed. They shared personal experiences, reflections, feelings, ideas...

  5. Interactive eshopping experience: an empirical investigation 

    E-Print Network [OSTI]

    Mahfouz, Ahmed Yousry Mohamed

    2005-02-17

    effect on flow's cognitive enjoyment component. High interactivity level sites moderately increased cognitive enjoyment more than low interactivity level sites did. Eshopping experience strongly and positively influenced flow experience in terms...

  6. Flatback airfoil wind tunnel experiment.

    SciTech Connect (OSTI)

    Mayda, Edward A.; van Dam, C.P.; Chao, David D.; Berg, Dale E.

    2008-04-01

    A computational fluid dynamics study of thick wind turbine section shapes in the test section of the UC Davis wind tunnel at a chord Reynolds number of one million is presented. The goals of this study are to validate standard wind tunnel wall corrections for high solid blockage conditions and to reaffirm the favorable effect of a blunt trailing edge or flatback on the performance characteristics of a representative thick airfoil shape prior to building the wind tunnel models and conducting the experiment. The numerical simulations prove the standard wind tunnel corrections to be largely valid for the proposed test of 40% maximum thickness to chord ratio airfoils at a solid blockage ratio of 10%. Comparison of the computed lift characteristics of a sharp trailing edge baseline airfoil and derived flatback airfoils reaffirms the earlier observed trend of reduced sensitivity to surface contamination with increasing trailing edge thickness.

  7. Quantifying entanglement with scattering experiments

    E-Print Network [OSTI]

    O. Marty; M. Epping; H. Kampermann; D. Bruß; M. B. Plenio; M. Cramer

    2013-10-03

    We show how the entanglement contained in states of spins arranged on a lattice may be quantified with observables arising in scattering experiments. We focus on the partial differential cross-section obtained in neutron scattering from magnetic materials but our results are sufficiently general such that they may also be applied to, e.g., optical Bragg scattering from ultracold atoms in optical lattices or from ion chains. We discuss resonating valence bond states and ground and thermal states of experimentally relevant models--such as Heisenberg, Majumdar-Ghosh, and XY model--in different geometries and with different spin numbers. As a by-product, we find that for the one-dimensional XY model in a transverse field such measurements reveal factorization and the quantum phase transition at zero temperature.

  8. SOURCE PHENOMENOLOGY EXPERIMENTS IN ARIZONA

    SciTech Connect (OSTI)

    Jessie L. Bonner; Brian Stump; Mark Leidig; Heather Hooper; Xiaoning (David) Yang; Rongmao Zhou; Tae Sung Kim; William R. Walter; Aaron Velasco; Chris Hayward; Diane Baker; C. L. Edwards; Steven Harder; Travis Glenn; Cleat Zeiler; James Britton; James F. Lewkowicz

    2005-09-30

    The Arizona Source Phenomenology Experiments (SPE) have resulted in an important dataset for the nuclear monitoring community. The 19 dedicated single-fired explosions and multiple delay-fired mining explosions were recorded by one of the most densely instrumented accelerometer and seismometer arrays ever fielded, and the data have already proven useful in quantifying confinement and excitation effects for the sources. It is very interesting to note that we have observed differences in the phenomenology of these two series of explosions resulting from the differences between the relatively slow (limestone) and fast (granodiorite) media. We observed differences at the two SPE sites in the way the rock failed during the explosions, how the S-waves were generated, and the amplitude behavior as a function of confinement. Our consortium's goal is to use the synergy of the multiple datasets collected during this experiment to unravel the phenomenological differences between the two emplacement media. The data suggest that the main difference between single-fired chemical and delay-fired mining explosion seismograms at regional distances is the increased surface wave energy for the latter source type. The effect of the delay-firing is to decrease the high-frequency P-wave amplitudes while increasing the surface wave energy because of the longer source duration and spall components. The results suggest that the single-fired explosions are surrogates for nuclear explosions in higher frequency bands (e.g., 6-8 Hz Pg/Lg discriminants). We have shown that the SPE shots, together with the mining explosions, are efficient sources of S-wave energy, and our next research stage is to postulate the possible sources contributing to the shear-wave energy.

  9. Current experiments in elementary particle physics. Revision

    SciTech Connect (OSTI)

    Galic, H. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Armstrong, F.E. [Lawrence Berkeley Lab., CA (United States); von Przewoski, B. [Indiana Univ. Cyclotron Facility, Bloomington, IN (United States)] [and others

    1994-08-01

    This report contains summaries of 568 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1988 are excluded. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, INS (Tokyo), ITEP (Moscow), IUCF (Bloomington), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

  10. NOvA Experiment - The Local Community

    ScienceCinema (OSTI)

    Deb Wieber

    2010-01-08

    Local proprietors Steve and Deb Wieber discuss the impact of the NOvA experiment on their community.

  11. Experiments on eta-meson production

    SciTech Connect (OSTI)

    Peng, J.C.

    1985-01-01

    Following a review of some highlights of eta-meson characteristics, the status of eta-meson production experiments is reviewed. The physics motivations and first results of two LAMPF experiments on (..pi..,eta) reactions are discussed. Possible future experiments are also discussed. 42 refs., 12 figs., 4 tabs.

  12. Talking about Tactile Experiences Marianna Obrist1

    E-Print Network [OSTI]

    Subramanian, Sriram

    experiences. We propose 14 categories for a human- experiential vocabulary based on the categorization mechanoreceptors. Author Keywords Tactile experiences; human-experiential vocabulary; user study; mechanoreceptors experiences [35]. For this study we used a haptic system to generate acoustic radiation pressures modulated

  13. Janus Experiments: Data from Mouse Irradiation Experiments 1972 - 1989

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Janus Experiments, carried out at Argonne National Laboratory from 1972 to 1989 and supported by grants from the US Department of Energy, investigated the effects of neutron and gamma radiation on mouse tissues primarily from B6CF1 mice. 49,000 mice were irradiated: Death records were recorded for 42,000 mice; gross pathologies were recorded for 39,000 mice; and paraffin embedded tissues were preserved for most mice. Mouse record details type and source of radiation [gamma, neutrons]; dose and dose rate [including life span irradiation]; type and presence/absence of radioprotector treatment; tissue/animal morphology and pathology. Protracted low dose rate treatments, short term higher dose rate treatments, variable dose rates with a same total dose, etc. in some cases in conjunction with radioprotectors, were administered. Normal tissues, tumors, metastases were preserved. Standard tissues saved were : lung, liver, spleen, kidney, heart, any with gross lesions (including mammary glands, Harderian gland with eye, adrenal gland, gut, ovaries or testes, brain and pituitary, bone). Data are searchable and specimens can be obtained by request.

  14. Today and Future Neutrino Experiments at Krasnoyarsk Nuclear Reactor

    E-Print Network [OSTI]

    Yu. V. Kozlov; S. V. Khalturtsev; I. N. Machulin; A. V. Martemyanov; V. P. Martemyanov; A. A. Sabelnikov; V. G. Tarasenkov; E. V. Turbin; V. N. Vyrodov; L. A. Popeko; A. V. Cherny; G. A. Shishkina

    1999-12-22

    The results of undergoing experiments and new experiment propositions at Krasnoyarsk underground nuclear reactor are presented

  15. Central Equatorial Pacific Experiment (CEPEX)

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Earth's climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27[degree]C, but never 31[degree]C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  16. PXIE: Project X Injector Experiment

    SciTech Connect (OSTI)

    Ostroumov, P.N.; /Argonne; Holmes, S.D.; Kephart, R.D.; Kerby, J.S.; Lebedev, V.A.; Mishra, C.S.; Nagaitsev, S.; Shemyakin, A.V.; Solyak, N.; Stanek, R.P.; /Fermilab; Li, D.; /LBL, Berkeley

    2012-05-01

    A multi-MW proton facility, Project X, has been proposed and is currently under development at Fermilab. We are planning a program of research and development aimed at integrated systems testing of critical components comprising the front end of the Project X. This program is being undertaken as a key component of the larger Project X R&D program. The successful completion of this program will validate the concept for the Project X front end, thereby minimizing a primary technical risk element within Project X. Integrated systems testing, known as the Project X Injector Experiment (PXIE), will be accomplished with a new test facility under construction at Fermilab and will be completed over the period FY12-16. PXIE will include an H{sup -} ion source, a CW 2.1-MeV RFQ and two superconductive RF (SRF) cryomodules providing up to 25 MeV energy gain at an average beam current of 1 mA (upgradable to 2 mA). Successful systems testing will also demonstrate the viability of novel front end technologies that are expected find applications beyond Project X.

  17. Major Milestone: PPPL completes first quadrant of the heart of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Major Milestone: PPPL completes first quadrant of the heart of the National Spherical Torus Experiment Upgrade By John Greenwald March 18, 2013 Tweet Widget Google Plus One Share...

  18. A Snowflake-Shaped Magnetic Field Holds Promise for Taming Harsh...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Torus Experiment The Science Heat escaping from the core of a twelve-million degree nuclear fusion plasma device was successfully contained by a snowflake-shaped magnetic...

  19. Current Experiments in Particle Physics (September 1996)

    SciTech Connect (OSTI)

    Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S.; Khachaturov, B.A.; Strokovsky, E.A.; Hoffman, C.M.; Kettle, P.-R.; Olin, A.; Armstrong, F.E.

    1996-09-01

    This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.

  20. The XENON100 Dark Matter Experiment

    SciTech Connect (OSTI)

    Tziaferi, E.

    2010-06-23

    The XENON100 experiment is searching for WIMPs, which are particles that may consist dark matter. It is located in the underground laboratory of Gran Sasso (LNGS) in Italy at a depth of {approx}3600 m.w.e.. The experiment description, its performance and the expected background based on Monte Carlo simulations and material screening along with the projected sensitivities of the experiment are presented. In addition, a brief description of the upgrade XENON100 detector is given.

  1. NNSA releases Stockpile Stewardship Program quarterly experiments...

    National Nuclear Security Administration (NNSA)

    National Ignition Facility at Lawrence Livermore National Laboratory, and the Z machine at Sandia National Laboratories. The summary also provides the number of experiments...

  2. Hampton University Scientists Complete Historic Experiment |...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    toward understanding the world we live in. The experiments used Jefferson Lab's high energy accelerator and experimental equipment to produce kaons pronounced Ka- onz,...

  3. Fuel Cell Power Plant Experience Naval Applications

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    reliable, efficient, ultra-clean Fuel Cell Power Plant Experience Naval Applications US Department of Energy Office of Naval Research Shipboard Fuel Cell Workshop Washington, DC...

  4. Fermilab Today | Experiment Profiles Archive | DES & DECam

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    their shapes, how galaxies cluster and the brightness of exploding stars called supernovae. WHY IS THIS EXPERIMENT NEEDED NOW? Research during the last decade using different...

  5. International Collaborations on Engineered Barrier Systems: Experiment...

    Energy Savers [EERE]

    interaction to evaluate sealing and clay barrier performance; 2) EBS Experiment -thermo-hydro-mechanical-chemical (THMC) behavior of the EBS under heating conditions and...

  6. Operating Experience Level 3: Radiologically Contaminated Respirators...

    Energy Savers [EERE]

    Experience Level 3 provides information on a safety concern related to radiological contamination of launderedreconditioned respirators and parts that have been certified as...

  7. Review of double beta decay experiments

    E-Print Network [OSTI]

    A. S. Barabash

    2014-03-12

    The brief review of current experiments on search and studying of double beta decay processes is done. Best present limits on $\\langle m_{\

  8. Hydrogen Embrittlement Fundamentals, Modeling, and Experiment...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen Embrittlement Fundamentals, Modeling, and Experiment Embrittlement, under static load could be a result of the synergistic action of the HELP and decohesion...

  9. Conference Proceedings Available - The Smart Grid Experience...

    Office of Environmental Management (EM)

    Applying Results, Reaching Beyond Conference Proceedings Available - The Smart Grid Experience: Applying Results, Reaching Beyond March 23, 2015 - 10:55am Addthis In...

  10. Current experiments in elementary particle physics

    SciTech Connect (OSTI)

    Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P. (Lawrence Berkeley Lab., CA (USA)); Oyanagi, Y. (Tsukuba Univ., Ibaraki (Japan)); Dodder, D.C. (Los Alamos National Lab., NM (USA)); Ryabov, Yu.G.; Slabospitsky, S.R. (Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Serpukhov (USSR). Inst. Fiziki Vysokikh Ehnergij); Frosch, R. (Swiss Inst. for Nuclear Research, Villigen (Switzerla

    1989-09-01

    This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  11. Current experiments in elementary particle physics. Revised

    SciTech Connect (OSTI)

    Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Wohl, C.G.; Armstrong, B. [Lawrence Berkeley Lab., CA (United States); Dodder, D.C. [Los Alamos National Lab., NM (United States); Klyukhin, V.I.; Ryabov, Yu.G. [Inst. for High Energy Physics, Serpukhov (Russian Federation); Illarionova, N.S. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); Lehar, F. [CEN Saclay, Gif-sur-Yvette (France); Oyanagi, Y. [Univ. of Tokyo (Japan). Faculty of Sciences; Olin, A. [TRIUMF, Vancouver, BC (Canada); Frosch, R. [Paul Scherrer Inst., Villigen (Switzerland)

    1992-06-01

    This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

  12. Current experiments in elementary particle physics

    SciTech Connect (OSTI)

    Wohl, C.G.; Armstrong, F.E., Oyanagi, Y.; Dodder, D.C.; Ryabov, Yu.G.; Frosch, R.; Olin, A.; Lehar, F.; Moskalev, A.N.; Barkov, B.P.

    1987-03-01

    This report contains summaries of 720 recent and current experiments in elementary particle physics (experiments that finished taking data before 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  13. Research Experience in Carbon Sequestration Training Program...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Training Program Now Accepting Applications Research Experience in Carbon Sequestration Training Program Now Accepting Applications March 26, 2012 - 1:00pm Addthis Washington, D.C....

  14. Scaling the practical education experience Joel Sommers

    E-Print Network [OSTI]

    Haddadi, Hamed

    Scaling the practical education experience Joel Sommers Colgate University jsommers outline a successful This work was done in part while Joel Sommers was visiting the University

  15. The NA62 Experiment at CERN

    E-Print Network [OSTI]

    Martellotti, Silvia

    2015-01-01

    The main physics goal of the NA62 experiment at CERN is to precisely measure the branching ratio of the Kaon rare decay $K^+\\rightarrow \\pi^+ \

  16. INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT, MONTICELLO, SOUTH CAROLINA

    E-Print Network [OSTI]

    Narasimhan, T.N.

    2014-01-01

    Letters INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT,12091 INTERPRETATION OF A HYDRAULIC FRACTURING EXPERIMENT,transient data from a hydraulic fracturing experiment have

  17. Experience curves for power plant emission control technologies

    E-Print Network [OSTI]

    Rubin, Edward S.; Yeh, Sonia; Hounshell, David A; Taylor, Margaret R

    2007-01-01

    2004) ‘Experience curves for power plant emission controlLtd. Experience curves for power plant emission controlInc. Experience curves for power plant emission control

  18. Dispatcher Reliability Analysis : SPICA-RAIL Experiments

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    consider that humans are fully reliable. But experience shows that many accidents involve human failuresDispatcher Reliability Analysis : SPICA-RAIL Experiments Fabien Belmonte, Jean-Louis Boulanger of scenarios and evaluate the behaviour of human operators. A state of the art in human reliability is pre

  19. NASA Cold Land Processes Field Experiment

    E-Print Network [OSTI]

    NASA Cold Land Processes Field Experiment Overview and Preliminary Results NASA Cold Land Processes Field Experiment Overview and Preliminary Results NASA Cold Land ProcessesNASA Cold Land Processes Field properties using active and passive microwave remote sensing. NASA DC-8 Airborne Laboratory with AIRSAR

  20. Geotechnical Engineering at the Waterways Experiment Station

    E-Print Network [OSTI]

    motions, advanced methods of site characterization, liquefaction po tentia l of fine-grained and gra vellyGEOSPEC Geotechnical Engineering at the Waterways Experiment Station The Geotechnical Laboratory at the U.S. Army Engineer Waterways Experi ment Station (WES) was founded in 1932 and currently