The National Ignition Facility and the Golden Age of High Energy Density Science (open access)

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

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 matter at extreme densities and temperatures.
Date: August 14, 2007
Creator: Moses, Edward
Object Type: Article
System: The UNT Digital Library
Amplitude variations on the Extreme Adaptive Optics testbed (open access)

Amplitude variations on the Extreme Adaptive Optics testbed

High-contrast adaptive optics systems, such as those needed to image extrasolar planets, are known to require excellent wavefront control and diffraction suppression. At the Laboratory for Adaptive Optics on the Extreme Adaptive Optics testbed, we have already demonstrated wavefront control of better than 1 nm rms within controllable spatial frequencies. Corresponding contrast measurements, however, are limited by amplitude variations, including those introduced by the micro-electrical-mechanical-systems (MEMS) deformable mirror. Results from experimental measurements and wave optic simulations of amplitude variations on the ExAO testbed are presented. We find systematic intensity variations of about 2% rms, and intensity variations with the MEMS to be 6%. Some errors are introduced by phase and amplitude mixing because the MEMS is not conjugate to the pupil, but independent measurements of MEMS reflectivity suggest that some error is introduced by small non-uniformities in the reflectivity.
Date: August 14, 2007
Creator: Evans, Julia; Thomas, Sandrine; Dillon, Daren; Gavel, Donald; Phillion, Donald & Macintosh, Bruce
Object Type: Article
System: The UNT Digital Library
Design of the Beam Delivery System for the International Linear Collider (open access)

Design of the Beam Delivery System for the International Linear Collider

The beam delivery system for the linear collider focuses beams to nanometer sizes at its interaction point, collimates the beam halo to provide acceptable background in the detector and has a provision for state-of-the art beam instrumentation in order to reach the ILCs physics goals. This paper describes the design details and status of the baseline configuration considered for the reference design and also lists alternatives.
Date: August 14, 2007
Creator: Seryi, A.; Amann, J.; Arnold, R.; Asiri, F.; Bane, K.; Bellomo, P. et al.
Object Type: Article
System: The UNT Digital Library
Ultra-Intense-laser produced high-Z backlighters for Compton Radiography (open access)

Ultra-Intense-laser produced high-Z backlighters for Compton Radiography

None
Date: August 14, 2007
Creator: Tommasini, R
Object Type: Article
System: The UNT Digital Library
Final Report to the Department of the Energy for Project Entitled Rare Isotope Science Assessment Committee (open access)

Final Report to the Department of the Energy for Project Entitled Rare Isotope Science Assessment Committee

The Rare Isotope Science Assessment Committee (RISAC) was convened by the National Research Council in response to an informal request from the DOE’s Office of Nuclear Physics and the White House Office of Management and Budget. The charge to the committee is to examine and assess the broader scientific and international contexts of a U.S.-based rare-isotope facility. The committee met for the first time on December 16-17, 2005, in Washington, DC, and held three subsequent meetings. The committee’s final report was publicly released in unedited, prepublication form on Friday, December 8, 2006. The report was published in full-color by the National Academies Press in April 2007. Copies of the report were distributed to key decision makers and stakeholders around the world.
Date: August 14, 2007
Creator: Shapero, Donald & Meyer, Timothy I.
Object Type: Report
System: The UNT Digital Library
Material Damage Test for ILC Collimators (open access)

Material Damage Test for ILC Collimators

Simulations were completed to determine the energy deposition of an ILC bunch using FLUKA, Geant4 and EGS4 to a set of different spoiler designs. These shower simulations were used as inputs to thermal and mechanical studies using ANSYS. This paper presents a proposal to optimize the material choice and mechanical design of ILC spoilers jaws using ATF and benchmark the energy deposition simulations and the ANSYS studies giving the researchers valuable data which will help achieve a definitive ILC spoiler design.
Date: August 14, 2007
Creator: Fernandez Hernando, J.L.; /Daresbury; Blair, G.A.; Boogert, S.T.; /Royal Holloway, U. of London; Ellwood, G.E. et al.
Object Type: Article
System: The UNT Digital Library
Design of the Beam Delivery System for the International Linear Collider (open access)

Design of the Beam Delivery System for the International Linear Collider

None
Date: August 14, 2007
Creator: Seryi, A.; Amann, J.; Arnold, R.; Asiri, F.; Bane, K.; Bellomo, P. et al.
Object Type: Article
System: The UNT Digital Library
Geostatistical and Stochastic Study of Flow and Transport in the Unsaturated Zone at Yucca Mountain (open access)

Geostatistical and Stochastic Study of Flow and Transport in the Unsaturated Zone at Yucca Mountain

Yucca Mountain has been proposed by the U.S. Department of Energy as the nation’s long-term, permanent geologic repository for spent nuclear fuel or high-level radioactive waste. The potential repository would be located in Yucca Mountain’s unsaturated zone (UZ), which acts as a critical natural barrier delaying arrival of radionuclides to the water table. Since radionuclide transport in groundwater can pose serious threats to human health and the environment, it is important to understand how much and how fast water and radionuclides travel through the UZ to groundwater. The UZ system consists of multiple hydrogeologic units whose hydraulic and geochemical properties exhibit systematic and random spatial variation, or heterogeneity, at multiple scales. Predictions of radionuclide transport under such complicated conditions are uncertain, and the uncertainty complicates decision making and risk analysis. This project aims at using geostatistical and stochastic methods to assess uncertainty of unsaturated flow and radionuclide transport in the UZ at Yucca Mountain. Focus of this study is parameter uncertainty of hydraulic and transport properties of the UZ. The parametric uncertainty arises since limited parameter measurements are unable to deterministically describe spatial variability of the parameters. In this project, matrix porosity, permeability and sorption coefficient of the reactive tracer …
Date: August 14, 2007
Creator: Ye, Ming; Pan, Feng; Hu, Xiaolong & Zhu, Jianting
Object Type: Report
System: The UNT Digital Library
Technical Challenges for the Head-on Collisions and Extraction at the ILC (open access)

Technical Challenges for the Head-on Collisions and Extraction at the ILC

An interaction region with head-on collisions is considered as an alternative to the baseline ILC configuration. Progress in the final focus optics design includes engineered large bore superconducting final doublet magnets and their 3D magnetic integration in the detector solenoids. Progress on the beam separation optics is based on technical designs of electrostatic separator and special extraction quadrupoles. The spent beam extraction is realized by a staged collimation scheme relying on realistic collimators.
Date: August 14, 2007
Creator: Napoly, O.; Delferriere, O.; Durante, M.; Payet, J.; Rippon, C.; Uriot, D. et al.
Object Type: Article
System: The UNT Digital Library
Design of the Beam Delivery System for the International Linear Collider (open access)

Design of the Beam Delivery System for the International Linear Collider

None
Date: August 14, 2007
Creator: Seryi, A.; Amann, J.; Arnold, R.; Asiri, F.; Bane, K.; Bellomo, P. et al.
Object Type: Article
System: The UNT Digital Library
Aquifer Tube Sampling Along the 100-N Area Shoreline (open access)

Aquifer Tube Sampling Along the 100-N Area Shoreline

This report contains citrate data for groundwaters received from the 100-N Area. On April 4, 2007, 7 water samples were received from the 100-N Area for citrate analysis. The analyses for this project were performed at the 325 building located in the 300 Area of the Hanford Site. The analyses were performed according to Pacific Northwest National Laboratory (PNNL) approved procedures. The data sets include the sample identification numbers, analytical results, estimated quantification limits (EQL) and quality control data.
Date: August 14, 2007
Creator: Lindberg, Michael J. & Valenta, Michelle M.
Object Type: Report
System: The UNT Digital Library
Controlling Stimulated Brillouin Backscatter with Beam Smoothing in Weakly Damped Systems (open access)

Controlling Stimulated Brillouin Backscatter with Beam Smoothing in Weakly Damped Systems

None
Date: August 14, 2007
Creator: Divol, L
Object Type: Article
System: The UNT Digital Library