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Uncertainty Analysis Technique for OMEGA Dante Measurements

Description: The Dante is an 18 channel X-ray filtered diode array which records the spectrally and temporally resolved radiation flux from various targets (e.g. hohlraums, etc.) at X-ray energies between 50 eV to 10 keV. It is a main diagnostics installed on the OMEGA laser facility at the Laboratory for Laser Energetics, University of Rochester. The absolute flux is determined from the photometric calibration of the X-ray diodes, filters and mirrors and an unfold algorithm. Understanding the errors on thi… more
Date: May 7, 2010
Creator: May, M J; Widmann, K; Sorce, C; Park, H & Schneider, M
Partner: UNT Libraries Government Documents Department
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National Ignition Campaign Hohlraum Energetics

Description: The first series of experiments on the National Ignition Facility (NIF) [E. I. Moses, R. N. Boyd, B. A. Remington, C. J. Keane, and R. Al-Ayat, 'The National Ignition Facility: ushering in a new age for high energy density science,' Phys. Plasmas 16, 041006 (2009)] tested ignition hohlraum 'energetics,' a term described by four broad goals: (1) Measurement of laser absorption by the hohlraum; (2) Measurement of the x-ray radiation flux (T{sub RAD}{sup 4}) on the surrogate ignition capsule; (3) … more
Date: November 16, 2009
Creator: Meezan, N B; Atherton, L J; Callahan, D A; Dewald, E L; Dixit, S N; Dzenitis, E G et al.
Partner: UNT Libraries Government Documents Department
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Simulation of Electric Field in Semi Insulating Au/CdTe/Au Detector under Flux

Description: We report our simulations on the profile of the electric field in semi insulating CdTe and CdZnTe with Au contacts under radiation flux. The type of the space charge and electric field distribution in the Au/CdTe/Au structure is at high fluxes result of a combined influence of charge formed due to band bending at the electrodes and from photo generated carriers, which are trapped at deep levels. Simultaneous solution of drift-diffusion and Poisson equations is used for the calculation. We show,… more
Date: August 2, 2009
Creator: Franc, J.; James, R.; Grill, R.; Kubat, J.; Belas, E.; Hoschl, P. et al.
Partner: UNT Libraries Government Documents Department
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X-ray Conversion Efficiency of high-Z hohlraum wall materials for indirect drive ignition

Description: We measure the conversion efficiency of 351 nm laser light to soft x-rays (0.1-5 keV) for Au, U and high Z mixtures 'cocktails' used for hohlraum wall materials in indirect drive ICF. We use spherical targets in a direct drive geometry, flattop laser pulses and laser smoothing with phase plates to achieve constant and uniform laser intensities of 10{sup 14} and 10{sup 15} W/cm{sup 2} over the target surface that are relevant for the future ignition experiments on NIF. The absolute time and spec… more
Date: February 22, 2008
Creator: Dewald, E; Rosen, M; Glenzer, S H; Suter, L J; Girard, F; Jadaud, J P et al.
Partner: UNT Libraries Government Documents Department
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A High Repetition Rate VUV-Soft X-Ray FEL Concept

Description: We report on design studies for a seeded FEL light source that is responsive to the scientific needs of the future. The FEL process increases radiation flux by several orders of magnitude above existing incoherent sources, and offers the additional enhancements attainable by optical manipulations of the electron beam: control of the temporal duration and bandwidth of the coherent output, reduced gain length in the FEL, utilization of harmonics to attain shorter wavelengths, and precise synchron… more
Date: June 24, 2007
Creator: Corlett, J.; Byrd, J.; Fawley, W. M.; Gullans, M.; Li, D.; Lidia, S. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Physics of String Flux Compactifications

Description: We provide a qualitative review of flux compactifications of string theory, focusing on broad physical implications and statistical methods of analysis.
Date: February 20, 2007
Creator: Denef, Frederik; U., /Leuven; Douglas, Michael R.; /Rutgers U., Piscataway /IHES, Bures-sur-Yvette; Kachru, Shamit & /Stanford U., Phys. Dept. /SLAC
Partner: UNT Libraries Government Documents Department
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Probing Dark Energy via Neutrino and Supernova Observatories

Description: A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadolinium-enriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator. The core-collapse SN… more
Date: July 10, 2006
Creator: Hall, Lawrence; Hall, Lawrence J.; Murayama, Hitoshi; Papucci, Michele & Perez, Gilad
Partner: UNT Libraries Government Documents Department
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Phenomenological Theory of the Photoevaporation Front Instability

Description: The dynamics of photoevaporated molecular clouds is determined by the ablative pressure acting on the ionization front. An important step in the understanding of the ensuing motion is to develop the linear stability theory for the initially flat front. Despite the simplifications introduced by the linearization, the problem remains quite complex and still draws a lot of attention. The complexity is related to the large number of effects that have to be included in the analysis: acceleration of … more
Date: April 10, 2006
Creator: Ryutov, D. D.; Kane, J. O.; Mizuta, A.; Pound, M. W. & Remington, B. A.
Partner: UNT Libraries Government Documents Department
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Angularly Adaptive P1--Double P0 Diffusion Solutions of Non-Equilibrium Grey Radiative Transfer Problems in Planar Geometry

Description: The double spherical harmonics angular approximation in the lowest order, i.e. double P{sub 0} (DP{sub 0}), is developed for the solution of time-dependent non-equilibrium grey radiative transfer problems in planar geometry. The standard P{sub 1} angular approximation represents the angular dependence of the radiation specific intensity using a linear function in the angular domain -1 {le} {mu} {le} 1. In contrast, the DP{sub 0} angular approximation represents the angular dependence as isotrop… more
Date: June 6, 2005
Creator: Brantley, P S
Partner: UNT Libraries Government Documents Department
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Study of X-ray photoionized Fe plasma and comparisons with astrophysical modeling codes

Description: The charge state distributions of Fe, Na and F are determined in a photoionized laboratory plasma using high resolution x-ray spectroscopy. Independent measurements of the density and radiation flux indicate the ionization parameter {zeta} in the plasma reaches values {zeta} = 20-25 erg cm s{sup -1} under near steady-state conditions. A curve-of-growth analysis, which includes the effects of velocity gradients in a one-dimensional expanding plasma, fits the observed line opacities. Absorption l… more
Date: April 29, 2005
Creator: Foord, M E; Heeter, R F; Chung, H; vanHoof, P M; Bailey, J E; Cuneo, M E et al.
Partner: UNT Libraries Government Documents Department
open access

Numerical Modeling of Hohlraum Radiation Conditions: Spatial and Spectral Variations due to Sample Position, Beam Pointing, and Hohlraum Geometry

Description: View-factor simulations are presented of the spatially varying radiation conditions inside double-ended gold hohlraums and single-ended gold hohlraums (''halfraums'') used in inertial confinement fusion (ICF) and high energy density (HED) physics experiments [J. Lindl, Phys. Plasmas 11, 339 (2004); M. D. Rosen, Phys. Plasmas 3, 1803 (1996)]. It is shown that in many circumstances, the common assumption that the hohlraum ''drive'' can be characterized by a single temperature is too simplistic. S… more
Date: January 25, 2005
Creator: Cohen, D. H.; Landen, O. L. & MacFarlane, J. J.
Partner: UNT Libraries Government Documents Department
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A 20-year data set of surface longwave fluxes in the Arctic

Description: Creation of 20-year data set of surface infrared fluxes from satellite measurements. A reliable estimate of the surface downwelling longwave radiation flux (DLF) is a glaring void in available forcing data sets for models of Arctic sea ice and ocean circulation. We have developed a new method to estimate the DLF from a combination of satellite sounder retrievals and brightness temperatures from the TIROS Operational Vertical Sounder (TOVS), which has flown on NOAA polar-orbiting satellites cont… more
Date: June 15, 2004
Creator: Francis, Jennifer
Partner: UNT Libraries Government Documents Department
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TuPo2.XX SYMMETRY TUNING OF NIF IGNITION TARGETS

Description: We present the results of a study in which we reduced the calculated intrinsic radiation asymmetry of a particular indirectly-driven cryogenic DT ignition target design through a series of two-dimensional and three-dimensional radiation hydrodynamic calculations of the integrated hohlraum/capsule system. We reduced the amplitude of the time-dependent P{sub 2} Legendre mode of the radiation flux onto the capsule by adjusting the beam pointing and changing the amount of laser power in the outer c… more
Date: November 11, 2003
Creator: Jones, O. S.; Marinak, M. M.; Amendt, P. A.; Pollaine, S. M.; Herrmann, M. C.; Haan, S. W. et al.
Partner: UNT Libraries Government Documents Department
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Best Estimate Radiation Flux Value-Added Procedure: Algorithm Operational Details and Explanations

Description: This document describes some specifics of the algorithm for best estimate evaluation of radiation fluxes at Southern Great Plains (SGP) Central Facility (CF). It uses the data available from the three co-located surface radiometer platforms at the SGP CF to automatically determine the best estimate of the irradiance measurements available. The Best Estimate Flux (BEFlux) value-added procedure (VAP) was previously named Best Estimate ShortWave (BESW) VAP, which included all of the broadband and … more
Date: October 1, 2002
Creator: Shi, Y. & Long, C. N.
Partner: UNT Libraries Government Documents Department
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Indirect-Drive Noncryogenic Double-Shell Ignition Targets for the National Ignition Facility: Design and Analysis

Description: The central goal of the National Ignition Facility (NIF) is demonstration of controlled thermonuclear ignition. The mainline ignition target is a low-Z, single-shell cryogenic capsule designed to have weakly nonlinear Rayleigh-Taylor growth of surface perturbations. Double-shell targets are an alternative design concept that avoids the complexity of cryogenic preparation but has greater physics uncertainties associated with performance-degrading mix. A typical double-shell design involves a hig… more
Date: October 15, 2001
Creator: Amendt, P.; Colvin, J.; Tipton, R. E.; Hinkel, D.; Edwards, M. J.; Landen, O. L. et al.
Partner: UNT Libraries Government Documents Department
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Isolation of Microstructure in Proton-Irradiated Steels. Topical Report

Description: OAK B188 Isolation of Microstructure in Proton-Irradiated Steels. Topical Report. Component degradation by irradiation is a primary concern in both current reactor systems as well as advanced designs and concepts where the demand for higher efficiency and performance will be considerably greater. In advanced reactor systems, core components will be expected to operate under increasingly hostile (temperature, pressure, radiation flux, dose, etc.) conditions, The current strategy for assessing ra… more
Date: September 1, 2000
Creator: Was, G.S.; Atzmon, M. & Wang, L.
Partner: UNT Libraries Government Documents Department
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Preliminary Report on Supersonic Jet Modeling

Description: The report figures show the problem setup and radiation temperature (Tr) results for a simulation of a solid gold half-hohlraum irradiated with the 12 specified Omega laser beams using the incident pulse shape for shot 18080. The experimental package is not included in this modeling; the hohlraum has a solid gold wall at the experimental package position. Figure-1 shows the initial zoning and focusing of the two sets of laser beams. Figure 2 identifies the 4 regions over which we track the Tr a… more
Date: June 6, 2000
Creator: Lasinski, B.F.
Partner: UNT Libraries Government Documents Department
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How well do we need to know the beam properties at a neutrino factory?

Description: In principle, a neutrino factory can produce a beam with a well known {nu}{sub e} and {nu}{sub {mu}} flux. In practice, the uncertainties on the muon beam properties will introduce uncertainties into the calculated neutrino fluxes. The authors explore the relationship between the beam systematics and the systematic uncertainties on predicted event rates at a far site. The desired precision with which they must know the beam momentum, direction, divergence, momentum spread, and polarization are … more
Date: February 29, 2000
Creator: Geer, S. & Crisan, C.
Partner: UNT Libraries Government Documents Department
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Observation of the moon shadow in deep underground muon flux.

Description: A shadow of the moon, with a statistical significance of 5{sigma}, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with {sigma} {le}0.3{degree}. The position of the shadow confirms the alignment of the detector to better than 0.15{degree}. This alignment has remained stable during 10 years of data taking from 1989 through 1998.
Date: June 22, 1999
Creator: Allison, W. W. M.; Alner, G. J.; Ayres, D. S.; Cobb, J. H.; Fields, T. H.; Goodman, M. C. et al.
Partner: UNT Libraries Government Documents Department
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Search for neutrinos from active galactic nuclei in Soudan 2.

Description: Models for AGN neutrino production suggest a measurable muon flux in underground detectors in this paper we comment on neutrino point sources and discuss our methods for determining an upper limit on the intensity of horizontal, neutrino induced muons with energy above 1 TeV at the Soudan 2 detector. We set a limit of 1.8 x 10{sup {minus}13} (cm{sup 2} sr s){sup {minus}} for detecting 5 TeV {nu}-induced muons from AGN.
Date: June 22, 1999
Creator: DeMuth, D. M. & Collaboration, The Soudan 2
Partner: UNT Libraries Government Documents Department
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Fast Resistive Bolometry

Description: Resistive bolometry is an accurate, robust, spectrally broadband technique for measuring absolute x-ray fluence and flux. Bolometry is an independent technique for x-ray measurements that is based on a different set of physical properties than other diagnostics such as x-ray diodes, photoconducting detectors, and P-I-N diodes. Bolometers use the temperature-driven change in element resistivity to determine the total deposited energy. The calibration of such a device is based on fundamental mate… more
Date: February 1, 1999
Creator: Deeney, C.; Fehl, D. L.; Hanson, D. L.; Keltner, N. R.; McGurn, J. S.; McKenney, J. L. et al.
Partner: UNT Libraries Government Documents Department
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Determination of mixed proton/neutron fluences in the LANSCE irradiation environment

Description: In support of the Accelerator Production of Tritium (APT) program, several materials were exposed to a high-energy proton and spallation neutron environments. Large differences in mechanical property changes in this environment are expected compared to the typical fusion or fission systems. To make proper dose correlations, it is important to accurately quantify the fluences. Activation foils consisting of a stack of disks of Co, Ni, Fe, Al, Nb and Cu were irradiated concurrent with mechanical … more
Date: December 31, 1998
Creator: James, M. R.; Maloy, S. A; Sommer, W. F.; Ferguson, P.; Fowler, M. M. & Corzine, K.
Partner: UNT Libraries Government Documents Department
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Distributions of Alpha Particles Escaping to the Wall because of Sawtooth Oscillations in TFTR

Description: It has been observed experimentally in deuterium-tritium shots of the Tokamak Fusion Test Reactor (TFTR) that crashes of sawtooth oscillations may result in very inhomogeneous flux of alpha particles to the wall. Namely, measurements with four detectors installed at the wall at 20°, 45°, 60°, and 90° below the midplane of the torus have shown that the alpha flux to the wall is strongly peaked at the 20° and 90° detectors and on the noise level at the 45° detector. To explain this phenomenon, bo… more
Date: November 1, 1998
Creator: Kolesnichenko, Ya. I.; Lutsenko, V. V.; White, R. B. & Yakovenko, Yu. V.
Partner: UNT Libraries Government Documents Department
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Studies of modern and ancient solar energetic particles

Description: Modern solar energetic particles (SEPs) have been studied for about 50 years by satellites and ground-based observations. These measurements indicate much about the nature of SEPs but cover too short a period to quantify the probabilities of very large solar particle events. Many SEPs have high enough energies to make nuclides in material in which they interact. Some nuclides measured in lunar samples have been used to extend the record about SEPs back several million years. Some new measuremen… more
Date: October 1, 1998
Creator: Reedy, R. C.
Partner: UNT Libraries Government Documents Department
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