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Environmental Challenges for the Nuclear Diagnostics on the NIF and LMJ

Description: The National Ignition Facility (NIF) and Laser Mega Joule (LMJ) facilities are currently under construction in the United States and France. Ignited targets at these facilities are anticipated to produce up to 1019 deuterium-tritium fusion neutrons. This will provide unprecedented opportunities and challenges for the use of nuclear diagnostics in inertial confinement fusion experiments. The NIF and LMJ nuclear diagnostics will work in a harsh radiation environment that includes neutron, hard x-… more
Date: June 27, 2007
Creator: al., K. Miller et
Partner: UNT Libraries Government Documents Department
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Initial Study Comparing the Radiating Divertor Behavior in Single-Null and Double-Null Plasmas in DIII-D

Description: 'Puff and pump' radiating divertor scenarios [1,2] were applied to upper SN and DN H-mode plasmas. Under similar operating conditions, argon (Ar) accumulated in the main plasma of single-null (SN) plasmas more rapidly and reached a higher steady-state concentration when the B x {del}B ion drift direction was toward the divertor than when the B x {del}B ion drift direction was out of the divertor. The initial rate that Ar accumulated inside double-null (DN) plasmas was more than twice that of co… more
Date: June 27, 2007
Creator: Petrie, T; Brooks, N; Fenstermacher, M; Groth, M; Hyatt, A; Isler, R et al.
Partner: UNT Libraries Government Documents Department
open access

Coupled Reservoir-Geomechanical Analysis of the Potential for Tensile and Shear Failure Associated With CO2 Injection in Multilayered Reservoir-Caprock Systems

Description: Coupled reservoir-geomechanical simulations were conductedto study the potential for tensile and shear failure e.g., tensilefracturing and shear slip along pre-existing fractures associated withunderground CO2 injection in a multilayered geological system. Thisfailure analysis aimed to study factors affecting the potential forbreaching a geological CO2 storage system and to study methods forestimating the maximum CO2 injection pressure that could be sustainedwithout causing such a breach. We pa… more
Date: March 27, 2007
Creator: Rutqvist, J.; Birkholzer, J. T. & Tsang, C.-F.
Partner: UNT Libraries Government Documents Department
open access

Plasma Electrode Pockels Cell Subsystem Performance in the National Ignition Facility

Description: The Plasma Electrode Pockels Cell (PEPC) subsystem is a key component of the National Ignition Facility, enabling the laser to employ an efficient four-pass main amplifier architecture. PEPC relies on a pulsed power technology to initiate and maintain plasma within the cells and to provide the necessary high voltage bias to the cells nonlinear crystals. Ultimately, nearly 300 high-voltage, high-current pulse generators will be deployed in the NIF in support of PEPC. Production of solid-state pl… more
Date: July 27, 2007
Creator: Barbosa, F.; Arnold, P.; Hinz, A.; Zacharias, R.; Ollis, C.; Fulkerson, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Electron Density Measurements in the National Spherical Torus Experiment Detached Divertor Region Using Stark Broadening of Deuterium Infrared Paschen Emission Lines

Description: Spatially resolved measurements of deuterium Balmer and Paschen line emission have been performed in the divertor region of the National Spherical Torus Experiment using a commercial 0.5 m Czerny-Turner spectrometer. While the Balmer emission lines, Balmer and Paschen continua in the ultraviolet and visible regions have been extensively used for tokamak divertor plasma temperature and density measurements, the diagnostic potential of infrared Paschen lines has been largely overlooked. We analyz… more
Date: April 27, 2007
Creator: Soukhanovskii, V A; Johnson, D W; Kaita, R & Roquemore, A L
Partner: UNT Libraries Government Documents Department
open access

FRONT-END ASIC FOR A SILICON COMPTON TELESCOPE.

Description: We describe a front-end application specific integrated circuit (ASIC) developed for a silicon Compton telescope. Composed of 32 channels, it reads out signals in both polarities from each side of a Silicon strip sensor, 2 mm thick 27 cm long, characterized by a strip capacitance of 30 pF. Each front-end channel provides low-noise charge amplification, shaping with a stabilized baseline, discrimination, and peak detection with an analog memory. The channels can process events simultaneously, an… more
Date: October 27, 2007
Creator: DE GERONIMO,G.; FRIED, J.; FROST, E.; PHLIPS, B.; VERNON, E. & WULF, E.A.
Partner: UNT Libraries Government Documents Department
open access

Monitoring the Thermal Power of Nuclear Reactors with a Prototype Cubic Meter Antineutrino Detector

Description: In this paper, we estimate how quickly and how precisely a reactor's operational status and thermal power can be monitored over hour to month time scales, using the antineutrino rate as measured by a cubic meter scale detector. Our results are obtained from a detector we have deployed and operated at 25 meter standoff from a reactor core. This prototype can detect a prompt reactor shutdown within five hours, and monitor relative thermal power to 3.5% within 7 days. Monitoring of short-term powe… more
Date: June 27, 2007
Creator: Bernstein, A; Bowden, N; Misner, A & Palmer, T
Partner: UNT Libraries Government Documents Department
open access

Radiation damage to BSCCO-2223 from 50 MEV protons.

Description: The use of HTS materials in high radiation environmentsrequires that the superconducting properties remain constant up to aradiation high dose. BSCCO-2223 samples from two manufacturers wereirradiated with 50 MeV protons at fluences of up to 5 x 1017 protons/cm2.The samples lost approximately 75 percent of their pre-irradiation Ic.This compares with Nb3Sn, which loses about 50 percent at the samedisplacements per atom.
Date: November 27, 2007
Creator: Zeller, A. F.; Ronningen, R. M.; Godeke, A.; Heilbronn, L. H.; McMahan-Norris, P. & Gupta, R.
Partner: UNT Libraries Government Documents Department
open access

Studies of Background Levels for the NIF Yield Diagnostics from Neutron and Gamma Radiation

Description: The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) is nearing completion of construction and is preparing for the National Ignition Campaign (NIC) with potentially significant yield in 2010. The design of a wide range of yield diagnostics in and outside the target-bay of the NIF must consider scattered background neutrons and neutron-induced gamma rays to measure neutrons and x-rays from target. The large and complex target chamber and facility make the calcul… more
Date: August 27, 2007
Creator: Song, P.; Eder, D.; Moran, M.; Landen, O.; O'Brien, D. & Hsing, W.
Partner: UNT Libraries Government Documents Department
open access

Modeling Dynamic Ductility: An Equation of State for Porous Metals

Description: Enhanced heating from shock compression of a porous material can potentially suppress or delay cracking of the material on subsequent expansion. In this paper we quantify the expected enhanced heating in an experiment in which a sector of a thin cylindrical shell is driven from the inside surface by SEMTEX high explosive ({approx}1 {micro}s FWHM pressure pulse with peak pressure {approx}21.5 GPa). We first derive an analytical equation of state (EOS) for porous metals, then discuss the coupling… more
Date: July 27, 2007
Creator: Colvin, J
Partner: UNT Libraries Government Documents Department
open access

The National Ignition Facility and the Golden Age of High Energy Density Science

Description: The National Ignition Facility (NIF) is a 192-beam Nd:glass laser facility being constructed at the Lawrence Livermore National Laboratory (LLNL) to conduct research in inertial confinement fusion (ICF) and high energy density (HED) science. When completed, NIF will produce 1.8 MJ, 500 TW of ultraviolet light, making it the world's largest and highest-energy laser system. The NIF is poised to become the world's preeminent facility for conducting ICF and fusion energy research and for studying m… more
Date: September 27, 2007
Creator: Meier, W; Moses, E I & Newton, M
Partner: UNT Libraries Government Documents Department
open access

A Steinberg-Guinan model for High-Pressure Carbon, Diamond Phase

Description: Since the carbon, diamond phase has such a high yield strength, dynamic simulations must account for strength even for strong shock waves ({approx} 3 Mbar). We have determined an initial parametrization of two strength models: Steinberg-Guinan (SG) and a modified or improved SG, that captures the high pressure dependence of the calculated shear modulus up to 10 Mbar. The models are based upon available experimental data and on calculated elastic moduli using robust density functional theory. Ad… more
Date: July 27, 2007
Creator: Orlikowski, D.; Correa, A.; Schwegler, E. & Klepeis, J.
Partner: UNT Libraries Government Documents Department
open access

Plans for Ignition Experiments on NIF

Description: The National Ignition Facility (NIF) is a 192-beam Nd-glass laser facility presently under construction at Lawrence Livermore National Laboratory (LLNL) in support of inertial confinement fusion (ICF) and high-energy-density (HED) science. NIF will produce 1.8 MJ, 500 TW of ultraviolet light, making it the world's largest and most powerful laser system. NIF will be the world's preeminent facility for the study of matter at extreme temperatures and densities and for producing and developing ICF.… more
Date: July 27, 2007
Creator: Moses, Edward
Partner: UNT Libraries Government Documents Department
open access

The Effect of Magnetic Field on the Position of HTS Leads and theCooler in the Services Tower of the MICE Focusing Magnet

Description: The MICE focusing solenoids have three 4 K coolers (two forthe superconducting magnet and one for the liquid absorber) and four HTSleads that feed the current to the focusing coils. The focusing solenoidsproduce large radial external fields when they operate with the polarityof the two coils in opposition (the gradient or flip mode). When the MICEfocusing coils operate at the same polarity (the solenoid or non-flipmode), the fields are much smaller and parallel to the axis of thesolenoid. The w… more
Date: August 27, 2007
Creator: Green, M. A.; Yang, S. Q.; Cobb, J.; Lau, P.; Lau, W. W.; Witte, H. et al.
Partner: UNT Libraries Government Documents Department
open access

Laser-plasma interaction in ignition relevant plasmas: benchmarking our 3D modelling capabilities versus recent experiments

Description: We have developed a new target platform to study Laser Plasma Interaction in ignition-relevant condition at the Omega laser facility (LLE/Rochester)[1]. By shooting an interaction beam along the axis of a gas-filled hohlraum heated by up to 17 kJ of heater beam energy, we were able to create a millimeter-scale underdense uniform plasma at electron temperatures above 3 keV. Extensive Thomson scattering measurements allowed us to benchmark our hydrodynamic simulations performed with HYDRA [1]. As… more
Date: September 27, 2007
Creator: Divol, L; Froula, D H; Meezan, N; Berger, R; London, R A; Michel, P et al.
Partner: UNT Libraries Government Documents Department
open access

SEMATECH EUV resist benchmarking results

Description: Extreme Ultraviolet Lithography (EUVL) is one of the leading candidates for next generation lithography technology for the 32 nm HP and beyond. The availability of EUV resists is one of the most significant challenges facing its commercialization. To accelerate EUV resist development, SEMATECH provides access to two exposure tools: (1) The EUV Resist Test Center (RTC) at SEMATECH at the University at Albany, SUNY, NY; and (2) the SEMATECH microexposure tools (ALS-MET) at Lawrence Berkeley Natio… more
Date: October 27, 2007
Creator: Ma, Andy; Park, Joo-On; Dean, Kim; Wurm, Stefan & Naulleau, Patrick
Partner: UNT Libraries Government Documents Department
open access

Simple but Stronger UO, Double but Weaker UNMe Bonds: The Tale Told by Cp2UO and Cp2UNR

Description: The free energies of reaction and the activation energies are calculated, with DFT (B3PW91) and small RECP (relativistic core potential) for uranium, for the reaction of Cp2UNMe and Cp2UO with MeCCMe and H3Si-Cl that yields the corresponding addition products. CAS(2,7) and DFT calculations on Cp2UO and Cp2UNMe give similar results, which validates the use of DFT calculations in these cases. The calculated results mirror the experimental reaction of [1,2,4-(CMe3)3C5H2]2UNMe with dimethylacetylen… more
Date: June 27, 2007
Creator: LPCNO, CNRS-UPS-INSA, INSA Toulouse; Institut Charles Gerhardt, CNRS, Universite Montpellier; Laboratoire de Chimie et Physique Quantiques, CNRS, IRSAMC, Universite Paul Sabatier; Andersen, Richard; Barros, Noemi; Maynau, Daniel et al.
Partner: UNT Libraries Government Documents Department
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The Engineering Design of the 1.5 m Diameter Solenoid for the MICERFCC Modules

Description: The RF coupling coil (RFCC) module of MICE is where muonsthat have been cooled within the MICE absorber focus (AFC) modules arere-accelerated to their original longitudinal momentum. The RFCC moduleconsists of four 201.25 MHz RF cavities in a 1.4 meter diameter vacuumvessel. The muons are kept within the RF cavities by the magnetic fieldgenerated by a superconducting coupling solenoid that goes around the RFcavities. The coupling solenoid will be cooled using a pair of 4 K pulsetube cooler that… more
Date: August 27, 2007
Creator: Wang, L.; Green, M. A.; Xu, F. Y.; Wu, H.; Li, L. K.; Gou, C. S. et al.
Partner: UNT Libraries Government Documents Department
open access

Characterization of Nuclear Fuel using Multivariate Statistical Analysis

Description: Various combinations of reactor type and fuel composition have been characterized using principle components analysis (PCA) of the concentrations of 9 U and Pu isotopes in the 10 fuel as a function of burnup. The use of PCA allows the reduction of the 9-dimensional data (isotopic concentrations) into a 3-dimensional approximation, giving a visual representation of the changes in nuclear fuel composition with burnup. Real-world variation in the concentrations of {sup 234}U and {sup 236}U in the … more
Date: November 27, 2007
Creator: Robel, M; Robel, M; Robel, M; Kristo, M J & Kristo, M J
Partner: UNT Libraries Government Documents Department
open access

The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume

Description: By various theorems one can relate the capital cost of superconducting magnets to the magnetic energy stored within that magnet. This is particularly true for magnet where the cost is dominated by the structure needed to carry the magnetic forces. One can also relate the cost of the magnet to the product of the magnetic induction and the field volume. The relationship used to estimate the cost the magnet is a function of the type of magnet it is. This paper updates the cost functions given in t… more
Date: August 27, 2007
Creator: Green, Mike; Green, M. A. & Strauss, B. P.
Partner: UNT Libraries Government Documents Department
open access

CRISPR - a Widespread System That Provides Acquired Resistance Against Phages in Bacteria and Archaea

Description: Arrays of clustered, regularly spaced short palindromic repeats (CRISPR) are widespread in the genomes of many bacteria and almost all archaea. These arrays are composed of direct repeats sized 24-47 bp separated by similarly sized non-repetitive sequences (spacers). It was recently experimentally shown that CRISPR arrays, along with a group of associated proteins, confer resistance to phage. Following exposure to phage, bacteria integrate new spacer sequences that are derived from the phage ge… more
Date: November 27, 2007
Creator: Kunin, Victor; Sorek, Rotem; Kunin, Victor & Hugenholtz, Philip
Partner: UNT Libraries Government Documents Department
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