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Z-Pinch Driven Inertial Confinement Fusion Target Physics Research at Sandia National Laboratories

Description: Three hohlraum concepts are being pursued at Sandia National Laboratories (SNL) to investigate the possibility of using pulsed power driven magnetic implosions (z-pinches) to drive high gain targets capable of yields in the range of 200-1000 MJ. This research is being conducted on SNL'S.Z facility that is capable of driving peak currents of 20 MA in z-pinch loads producing implosion velocities as high as 7.5X 107 cm/s, x-ray energies approaching 2 MJ, and x-ray powers exceeding 200 TW. This pap… more
Date: October 27, 1998
Creator: Alberts, T. E.; Asay, J. R.; Baca, P. M.; Baker, K. L.; Breeze, S. P.; Chandler, G. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proceedings of RIKEN BNL Resarch Center Workshop: Fluctuations, Correlations and RHIC Low Energy Runs

Description: Most of our visible universe is made up of hadronic matter. Quantum Chromodynamics (QCD) is the theory of strong interaction that describes the hadronic matter. However, QCD predicts that at high enough temperatures and/or densities ordinary hadronic matter ceases to exist and a new form of matter is created, the so-called Quark Gluon Plasma (QGP). Non-perturbative lattice QCD simulations shows that for high temperature and small densities the transition from the hadronic to the QCD matter is n… more
Date: October 27, 2011
Creator: Karsch, F.; Kojo, T.; Mukherjee, S.; Stephanov, M. & Xu, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Long Baseline Neutrino Beams and Large Detectors

Description: It is amazing to acknowledge that in roughly 70 years from when the existence of the neutrino was postulated, we are now contemplating investigating the mysteries of this particle (or particles) requiring and utilizing detectors of 300 ktons , distances of 1,000-2,000 kilometers, beam intensities of megawatts and underground depth of 5,000 feet. This evolution has evolved slowly, from the experimental discovery of the neutrino in 1956, to the demonstration that there were two neutrinos in 1962 … more
Date: October 27, 2008
Creator: Samios, N. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytical-scale separations of lanthanides : a review of techniques and fundamentals.

Description: Separations chemistry is at the heart of most analytical procedures to determine the rare earth content of both man-made and naturally occurring materials. Such procedures are widely used in mineral exploration, fundamental geology and geochemistry, material science, and in the nuclear industry. Chromatographic methods that rely on aqueous solutions containing complexing agents sensitive to the lanthanide cationic radius and cation-exchange phase transfer reactions (using a variety of different… more
Date: October 27, 1999
Creator: Nash, K. L. & Jensen, M. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Numerical Study of Global Stability of Oblate Field-Reversed Configurations

Description: Global stability of the oblate (small elongation, E < 1) Field-Reversed Configuration (FRC) has been investigated numerically using both three-dimensional magnetohydrodynamic (MHD) and hybrid (fluid electrons and kinetic ions) simulations. For every non-zero value of the toroidal mode number n, there are three MHD modes that must be stabilized. For n = 1, these are the interchange, the tilt and the radial shift; while for n > 1 these are the interchange and two co-interchange modes with d… more
Date: October 27, 2000
Creator: Belova, E. V.; Jardin, S. C.; Ji, H.; Yamada, M. & Kulsrud, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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

Description: Gas-Puff-Imaging (GPI) is a two dimensional diagnostic which measures the edge Dα 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 Dα light emission obtained by GPI on NSTX with DEGAS 2 simulations of Dα light emission for specific experiments. Both the simulated spatial distribution and absolute intensity of the Dα lig… more
Date: October 27, 2012
Creator: Cao, B.; Stotler, D. P.; Zweben, S. J.; Bell, M.; Diallo, A. & Leblanc, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Laboratory measurements of resonant contributions to Fe XXIV line emission

Description: A number of X-ray astronomy satellites are scheduled for launch in the next few years. The Advanced X-ray Astrophysics Facility (AXAF) is scheduled for launch in 1998, and the X-Ray Multi-mirror Mission (XMM) and Astro-E in 1999. These satellites will carry spectrometers with resolving powers in the Fe L-shell emission region over an order of magnitude greater than the spectrometers aboard A CA. Interpreting AXAF, XMM, Astro-E spectra will require atomic data at an accuracy significantly greate… more
Date: October 27, 1997
Creator: Gu, M.F.; Beiersdorfer, P.; Brown, G.V.; Kahn, S.M.; Liedahl, D.A.; Reed, K.J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geometry of wave electromagnetics

Description: A challenge to the commonly held view of light as a wave phenomenon is presented. An exact realization of light as generalized pencils or rays is constructed, with stress placed on using pencils of rays rather than single rays. Exact equations of motion are presented for the rays in the pencil, and these rays tend to travel in straight lines in empty space (not too near the edge of the beam). (GHT)
Date: October 27, 1980
Creator: Sudarshan, E. C.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Quantitative Experiments With Electrons in a Positively Charged Beam

Description: Intense ion beams are an extreme example of, and difficult to maintain as, a non-neutral plasma. Experiments and simulations are used to study the complex interactions between beam ions and (unwanted) electrons. Such ''electron clouds'' limit the performance of many accelerators. To characterize electron clouds, a number of parameters are measured including: total and local electron production and loss for each of three major sources, beam potential versus time, electron line-charge density, an… more
Date: October 27, 2006
Creator: Molvik, A W; Vay, J; Covo, M K; Cohen, R; Baca, D; Bieniosek, F et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transport and Fluctuations in High Temperature Spheromak Plasmas

Description: Globally coherent magnetic fluctuations often observed during the driven phase after spheromak formation in the Sustained Spheromak Physics Experiment (SSPX) can be reduced to small amplitude by programming the magnetic flux = {Psi}{sub gun} and the discharge current = I{sub gun} in the formation gun. Scanning the edge normalized current = {lambda}{sub edge} = {lambda}{sub gun} = {mu}{sub 0}I{sub gun}/{Psi}{sub gun} above and below the minimum energy eigenvalue = {lambda}{sub FC} of the flux co… more
Date: October 27, 2005
Creator: McLean, H. S.; Woodruff, S.; Wood, R. D.; Hooper, E. B.; Hill, D. N.; Moller, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Next-Step Spherical Torus Experiment and Spherical Torus Strategy in the Fusion Energy Development Path

Description: A spherical torus (ST) fusion energy development path which is complementary to proposed tokamak burning plasma experiments such as ITER is described. The ST strategy focuses on a compact Component Test Facility (CTF) and higher performance advanced regimes leading to more attractive DEMO and Power Plant scale reactors. To provide the physics basis for the CTF an intermediate step needs to be taken which we refer to as the ''Next Step Spherical Torus'' (NSST) device and examine in some detail h… more
Date: October 27, 2003
Creator: Ono, M.; Peng, M.; Kessel, C.; Neumeyer, C.; Schmidt, J.; Chrzanowski, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Future experiments with neutrino superbeams, beta-beams, and neutrino factories

Description: This report describes the goals of the next generations of accelerator-based neutrino experiments, and the various strategies that are being considered to achieve those goals. Because these next steps in the field are significantly different from the current or previous steps, novel techniques must be considered for both the detectors and the neutrino beams themselves. We consider not only conventional neutrino beams created by decays of pions, but also those which could be made by decays of be… more
Date: October 27, 2003
Creator: Harris, Deborah A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Results on diffraction at CDF

Description: In run I CDF made an extensive range of measurements studying diffractive processes. In run II these measurements can be extended using improved triggering, new detectors and larger data samples. In these proceedings run II measurements of single diffractive dijet production and double pomeron exchange production of dijets are presented.
Date: October 27, 2003
Creator: Wyatt, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

On Practical Modifications to the Barnes-Hut Multipole Method for Electromagnetic Scattering

Description: This paper presents a simple methodology for quickly predicting and optimizing computer run time for the Barnes-Hut multipole method for boundary element electromagnetic scattering problems. The methodology is easily extended to other multipole methods (e.g., Greengard-Rokhlin) and to other physics. The idea is to simply COZM t the number of element-cell interactions, number of direct element- element interactions, and the number of cell multipole expansion creations (each expansion weighted by… more
Date: October 27, 1998
Creator: Driessen, B. J. & Kotulski, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The $\hbar$ Expansion in Quantum Field Theory

Description: We show how expansions in powers of Planck's constant {h_bar} = h = 2{pi} can give new insights into perturbative and nonperturbative properties of quantum field theories. Since {h_bar} is a fundamental parameter, exact Lorentz invariance and gauge invariance are maintained at each order of the expansion. The physics of the {h_bar} expansion depends on the scheme; i.e., different expansions are obtained depending on which quantities (momenta, couplings and masses) are assumed to be independent … more
Date: October 27, 2010
Creator: Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; Hoyer, Paul & /Southern Denmark U., CP3-Origins /Helsinki U. /Helsinki Inst. of Phys.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Indirect-Drive Time Dependent Symmetry Diagnosis at NIF-Scale

Description: The scaling to NIF of current techniques used to infer the time-dependent flux asymmetries for indirectly-driven capsules is reviewed. We calculate that the projected accuracy for detecting the lowest mode asymmetries by a variety of techniques now meet the requirements for symmetry tuning for ignition. The scaling to NIF has also motivated the implementation of new, more efficient and hence less perturbative backlighting techniques which have recently provided high quality symmetry data during… more
Date: October 27, 1999
Creator: Landen, O. L.; Bradley, D. K.; Pollaine, S. M.; Amendt, P. A.; Glendinning, S. G.; Suter, L. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multi-beam Mossbauer scattering facility. Final technical report

Description: The Mossbauer instrument construction which was financed by the DOE grant of $74,065 and MU matching funds of $52,000 is essentially completed and awaiting installation at the Missouri University Research Reactor (MURR) facility. All of the DOE funds have been spent and all of the matching funds plus about $4,000 to $5,000 of additional physics department funds have been committed to finishing the first phase of the new instrument, QUEGS--II (for QUAsiElastic Gamma-ray Scattering--generation II… more
Date: October 27, 1994
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Understanding Modern Magnets through Conformal Mapping

Description: When I had to choose, within some narrow range, the topic of this paper, I received great help from a colleague in Berkeley and from Prof. Little when it was suggested that I should pick among the possible subjects of my talk the subject that Prof. Bloch would have enjoyed most. Since Prof. Bloch would prefer a scalpel over a sword every time, I hope and think that most people will approve my choice. When one intends to talk about a subject that is as old as conformal mapping and one does not w… more
Date: October 27, 1989
Creator: Halbach, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Large-Stroke Self-Aligned Vertical Comb Drive Actuators for Adaptive Optics Applications

Description: A high-stroke micro-actuator array was designed, modeled, fabricated and tested. Each pixel in the 4x4 array consists of a self-aligned vertical comb drive actuator. This micro-actuator array was designed to become the foundation of a micro-mirror array that will be used as a deformable mirror for adaptive optics applications. Analytical models combined with CoventorWare{reg_sign} simulations were used to design actuators that would move up to 10{micro}m in piston motion with 100V applied. Devi… more
Date: October 27, 2005
Creator: Carr, E. J.; Olivier, S. S. & Solgaard, O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Low-pressure ion source

Description: A low pressure ion source for a neutron source comprises a filament cathode and an anode ring. Approximately 150V is applied between the cathode and the anode. Other electrodes, including a heat shield, a reflector and an aperture plate with a focus electrode, are placed at intermediate potentials. Electrons from the filament drawn out by the plasma and eventually removed by the anode are contained in a magnetic field created by a magnet ring. Ions are formed by electron impact with deuterium o… more
Date: October 27, 1982
Creator: Bacon, F.M.; Brainard, J.P.; O'Hagan, J.B. & Walko, R.J.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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