LSST Dark Energy Science Final Report (open access)

LSST Dark Energy Science Final Report

Three decadal surveys recommend a large-aperture synoptic survey telescope (LSST) to allow time-domain and cosmological studies of distant objects. LLNL designed the optical system and also is expected to play a significant role in the engineering associated with the camera. Precision cosmology from ground-based instruments is in a sense terra incognita. Numerous systematic effects occur that would be minimal or absent in their space-based counterparts. We proposed developing some basic tools and techniques for investigating ''dark sector'' cosmological science with such next-generation, large-aperture, real-time telescopes. The critical research involved determining whether systematic effects might dominate the extremely small distortions (''shears'') in images of faint background galaxies. To address these issues we carried out a comprehensive data campaign and developed detailed computer simulations.
Date: February 15, 2007
Creator: Asztalos, S
Object Type: Report
System: The UNT Digital Library
Molecular Markers of Lung Cancer in MAYAK Workers (open access)

Molecular Markers of Lung Cancer in MAYAK Workers

The molecular mechanisms that result in the elevated risk for lung cancer associated with exposure to radiation have not been well characterized. Workers from the MAYAK nuclear enterprise are an ideal cohort in which to study the molecular epidemiology of cancer associated with radiation exposure and to identify the genes targeted for inactivation that in turn affect individual risk for radiation-induced lung cancer. Epidemiology studies of the MAYAK cohort indicate a significantly higher frequency for adenocarcinoma and squamous cell carcinoma (SCC) in workers than in a control population and a strong correlation between these tumor types and plutonium exposure. Two hypotheses will be evaluated through the proposed studies. First, radiation exposure targets specific genes for inactivation by promoter methylation. This hypothesis is supported by our recent studies with the MAYAK population that demonstrated the targeting of the p16 gene for inactivation by promoter methylation in adenocarcinomas from workers (1). Second, genes inactivated in tumors can serve as biomarkers for lung cancer risk in a cancer-free population of workers exposed to plutonium. Support for this hypothesis is based on exciting preliminary results of our nested, case-control study of persons from the Colorado cohort. In that study, a panel of methylation markers …
Date: February 15, 2007
Creator: Belinsky, Steven A.
Object Type: Report
System: The UNT Digital Library
Environmental Test Activity on the Flight Modules of the GLAST LAT Tracker (open access)

Environmental Test Activity on the Flight Modules of the GLAST LAT Tracker

The GLAST Large Area Telescope (LAT) is a gamma-ray telescope consisting of a silicon micro-strip detector tracker followed by a segmented CsI calorimeter and covered by a segmented scintillator anticoincidence system that will search for {gamma}-rays in the 20 MeV-300 GeV energy range. The results of the environmental tests performed on the flight modules (towers) of the Tracker are presented. The aim of the environmental tests is to verify the performance of the silicon detectors in the expected mission environment. The tower modules are subjected to dynamic tests that simulate the launch environment and thermal vacuum test that reproduce the thermal gradients expected on orbit. The tower performance is continuously monitored during the whole test sequence. The environmental test activity, the results of the tests and the silicon tracker performance are presented.
Date: February 15, 2007
Creator: Brigida, M.; Caliandro, A.; Favuzzi, C.; Fusco, P.; Gargano, F.; Giglietto, N. et al.
Object Type: Article
System: The UNT Digital Library
Performance of the Integrated Tracker Towers of the GLAST Large Area Telescope (open access)

Performance of the Integrated Tracker Towers of the GLAST Large Area Telescope

The GLAST Large Area Telescope (LAT) is a high energy gamma ray observatory, mounted on a satellite that will be own in 2007. The LAT tracker consists of an array of tower modules, equipped with planes of silicon strip detectors (SSDs) interleaved with tungsten converter layers. Photon detection is based on the pair conversion process; silicon strip detectors will reconstruct tracks of electrons and positrons. The instrument is actually being assembled. The first towers have been already tested and integrated at Stanford Linear Accelerator Center (SLAC). An overview of the integration stages of the main components of the tracker and a description of the pre-launch tests will be given. Experimental results on the performance of the tracker towers will be also discussed.
Date: February 15, 2007
Creator: Brigida, M.; Caliandro, A.; Favuzzi, C.; Fusco, P.; Gargano, F.; Giglietto, N. et al.
Object Type: Article
System: The UNT Digital Library
First Results From GLAST-LAT Integrated Towers Cosmic Ray Data Taking And Monte Carlo Comparison (open access)

First Results From GLAST-LAT Integrated Towers Cosmic Ray Data Taking And Monte Carlo Comparison

GLAST Large Area Telescope (LAT) is a gamma ray telescope instrumented with silicon-strip detector planes and sheets of converter, followed by a calorimeter (CAL) and surrounded by an anticoincidence system (ACD). This instrument is sensitive to gamma rays in the energy range between 20 MeV and 300 GeV. At present, the first towers have been integrated and pre-launch data taking with cosmic ray muons is being performed. The results from the data analysis carried out during LAT integration will be discussed and a comparison with the predictions from the Monte Carlo simulation will be shown.
Date: February 15, 2007
Creator: Brigida, M.; Caliandro, A.; Favuzzi, C.; Fusco, P.; Gargano, F.; Giordano, F. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Angle beta with Time-dependent CPAsymmetry in B0 to K+K-K0 Decays (open access)

Measurement of Angle beta with Time-dependent CPAsymmetry in B0 to K+K-K0 Decays

In the Standard Model (SM) of particle physics, the phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix [1, 2] is the only source of CP violation in the quark sector. Due to the interference between mixing and decay, this phase can be observed in measurements of time-dependent CP asymmetries of B{sup 0} mesons. In the SM, CP asymmetries in b {yields} s{bar s}s decays, such as B{sup 0} {yields} K{sup +}K{sup -}K{sup 0}, are expected to be nearly equal to those observed in tree-dominated b {yields} {bar c}s decays [3]. However, because in the SM the former are dominated by loop amplitudes, new particles in those loops potentially introduce new physics at the same order as the SM process. Within the SM, deviations from the expected CP asymmetries in B{sup 0} {yields} K{sup +}K{sup -}K{sup 0} decays depend on the Dalitz plot position, but are expected to be small and positive [4]. In particular, for the decay B{sup 0} {yields} {phi}K{sup 0} they are expected to be less than 4%. BABAR extracts the time-dependent CP-violation parameters by taking into account different amplitudes and phases across the B{sup 0} and {bar B}{sup 0} Dalitz plots, while Belle measures it separately for B{sup …
Date: February 15, 2007
Creator: Di Marco, Emanuele
Object Type: Article
System: The UNT Digital Library
Magnetic Dynamos and Stars (open access)

Magnetic Dynamos and Stars

Djehuty is a code that has been developed over the last five years by the Lawrence Livermore National Laboratory (LLNL), from earlier code designed for programmatic efforts. Operating in a massively parallel environment, Djehuty is able to model entire stars in 3D. The object of this proposal was to continue the effort to introduce magneto-hydrodynamics (MHD) into Djehuty, and investigate new classes of inherently 3D problems involving the structure, evolution and interaction of stars and planets. However, towards the end of the second year we discovered an unexpected physical process of great importance in the evolution of stars. Consequently for the third year we changed direction and concentrated on this process rather than on magnetic fields. Our new process was discovered while testing the code on red-giant stars, at the 'helium flash'. We found that a thin layer was regularly formed which contained a molecular-weight inversion, and which led therefore to Rayleigh-Taylor instability. This in turn led to some deeper-than-expected mixing, which has the property that (a) much {sup 3}He is consumed, and (b) some {sup 13}C is produced. These two properties are closely in accord with what has been observed over the last thirty years in red giants, whereas …
Date: February 15, 2007
Creator: Eggleton, P P
Object Type: Report
System: The UNT Digital Library
Recommendations for Remedial Action at Everest, Kansas. (open access)

Recommendations for Remedial Action at Everest, Kansas.

On September 7, 2005, the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) presented a Scoping Memo (Argonne 2005) for preliminary consideration by the Kansas Department of Health and Environment (KDHE). This document suggested possible remedial options for the carbon tetrachloride contamination in groundwater at Everest, Kansas. The suggested approaches were discussed by representatives of the KDHE, the CCC/USDA, and Argonne at the KDHE office in Topeka on September 8-9, 2005, along with other technical and logistic issues related to the Everest site. In response to these discussions, the KDHE recommended (KDHE 2005) evaluation of several remedial processes, either alone or in combination, as part of a Corrective Action Study (CAS) for Everest. The primary remedial processes suggested by the KDHE included the following: (1) Hydraulic control by groundwater extraction with aboveground treatment; (2) Air sparging-soil vapor extraction (SVE) in large-diameter boreholes; and (3) Phytoremediation. As a further outcome of the 2005 meeting and as a precursor to the proposed CAS, the CCC/USDA completed the following supplemental investigations at Everest to address several specific technical concerns discussed with the KDHE: (1) Construction of interpretive cross sections at strategic locations selected by the KDHE along the main plume migration …
Date: February 15, 2007
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Ultrafast, In Situ Probing of Shocked Solids at the Mesoscale and Beyond: A New Paradigm for Materials Dynamics (open access)

Ultrafast, In Situ Probing of Shocked Solids at the Mesoscale and Beyond: A New Paradigm for Materials Dynamics

Understanding material response under dynamic conditions and extreme pressures at the lattice level is important for being able to generate predictive models of material response. Despite many decades of study, material behavior is primarily inferred from bulk measurements on dynamically loaded samples or the microstructure from recovery experiments and not determined from lattice level measurements made in-situ at the relevant length scale of the governing physics. In the work described here, we report on progress made in advancing this frontier with research conducted under LDRD 04-ERD-071. Specifically, we present advances in, and applications of, dynamic x-ray diffraction, Extended X-ray Absorption Fine Structure and dynamic transmission electron microscopy.
Date: February 15, 2007
Creator: Lorenzana, Hector; Belak, James; Campbell, Geoffrey; King, Wayne; Nikkel, Daniel; Bradley, Keith et al.
Object Type: Report
System: The UNT Digital Library
SIMULATION OF CARGO CONTAINER INTERROGATION BY D-D NEUTRONS (open access)

SIMULATION OF CARGO CONTAINER INTERROGATION BY D-D NEUTRONS

High fidelity, three-dimensional computer models based on a CAD drawing of an intermodal cargo container, representative payload objects, and detector array panels were developed to simulate the underlying physical events taking place during active interrogation. These computer models are used to assess the performance of interrogation systems with different sources and detection schemes. In this presentation, we will show that the use oversimplified models, such as analyzing homogenized payloads only, can lead to errors in determining viable approaches for interrogation.
Date: February 15, 2007
Creator: Lou, Tak Pui & Antolak, Arlyn
Object Type: Article
System: The UNT Digital Library
Structural Diagnostics of CFRP Composite Aircraft Components by Ultrasonic Guided Waves and Built-In Piezoelectric Transducers (open access)

Structural Diagnostics of CFRP Composite Aircraft Components by Ultrasonic Guided Waves and Built-In Piezoelectric Transducers

To monitor in-flight damage and reduce life-cycle costs associated with CFRP composite aircraft, an autonomous built-in structural health monitoring (SHM) system is preferred over conventional maintenance routines and schedules. This thesis investigates the use of ultrasonic guided waves and piezoelectric transducers for the identification and localization of damage/defects occurring within critical components of CFRP composite aircraft wings, mainly the wing skin-to-spar joints. The guided wave approach for structural diagnostics was demonstrated by the dual application of active and passive monitoring techniques. For active interrogation, the guided wave propagation problem was initially studied numerically by a semi-analytical finite element method, which accounts for viscoelastic damping, in order to identify ideal mode-frequency combinations sensitive to damage occurring within CFRP bonded joints. Active guided wave tests across three representative wing skin-to-spar joints at ambient temperature were then conducted using attached Macro Fiber Composite (MFC) transducers. Results from these experiments demonstrate the importance of intelligent feature extraction for improving the sensitivity to damage. To address the widely neglected effects of temperature on guided wave base damage identification, analytical and experimental analyses were performed to characterize the influence of temperature on guided wave signal features. In addition, statistically-robust detection of simulated damage in a CFRP …
Date: February 15, 2007
Creator: Matt, Howard M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Tracking Multiple Topics for Finding Interesting Articles (open access)

Tracking Multiple Topics for Finding Interesting Articles

We introduce multiple topic tracking (MTT) for iScore to better recommend news articles for users with multiple interests and to address changes in user interests over time. As an extension of the basic Rocchio algorithm, traditional topic detection and tracking, and single-pass clustering, MTT maintains multiple interest profiles to identify interesting articles for a specific user given user-feedback. Focusing on only interesting topics enables iScore to discard useless profiles to address changes in user interests and to achieve a balance between resource consumption and classification accuracy. Also by relating a topic's interestingness to an article's interestingness, iScore is able to achieve higher quality results than traditional methods such as the Rocchio algorithm. We identify several operating parameters that work well for MTT. Using the same parameters, we show that MTT alone yields high quality results for recommending interesting articles from several corpora. The inclusion of MTT improves iScore's performance by 9% to 14% in recommending news articles from the Yahoo! News RSS feeds and the TREC11 adaptive filter article collection. And through a small user study, we show that iScore can still perform well when only provided with little user feedback.
Date: February 15, 2007
Creator: Pon, R K; Cardenas, A F; Buttler, D J & Critchlow, T J
Object Type: Article
System: The UNT Digital Library
THERMAL TESTING OF 9977 GENERAL PURPOSE FISSILE PACKAGE USING A POOL FIRE (open access)

THERMAL TESTING OF 9977 GENERAL PURPOSE FISSILE PACKAGE USING A POOL FIRE

The 9977/9978 General Purpose Fissile Package (GPFP), has been designed as a cost-effective, user-friendly replacement for the DOT 6M Specification Package for transporting Plutonium and Uranium metals and oxides. To ensure the capability of the 9977 GPFP to withstand the regulatory crush test, urethane foam was chosen for the impact absorbing overpack. As part of the package development it was necessary to confirm that the urethane foam overpack would provide the required protection for the containment vessel during the thermal test portion of the Hypothetical Accident Conditions Sequential Tests. Development tests of early prototypes were performed, using a furnace. Based on the results of the development tests, detailed design enhancements were incorporated into the final design. Examples of the definitive 9977 design configuration were subjected to an all-engulfing pool fire test, as part of the HAC Sequential Tests, to support the application for certification. Testing has confirmed the package's ability to withstand the HAC thermal tests.
Date: February 15, 2007
Creator: Smith, Allen C.; May, Cecil G.; Gelder, Lawrence F. & Abramczyk, Glenn A.
Object Type: Article
System: The UNT Digital Library
Sampling and Analysis Instruction for Evaluation of Residual Chromium Contamination in the Subsurface Soil at 100-C-7 (open access)

Sampling and Analysis Instruction for Evaluation of Residual Chromium Contamination in the Subsurface Soil at 100-C-7

This sampling and analysis instruction (SAI) provides the requirements for sample collection and laboratory analysis to evaluate the extent of hexavalent chromium contamination present in the soil below the 100-C-7 and 100-C-7:1 remedial action waste site excavations.
Date: February 15, 2007
Creator: Thompson, W. S.
Object Type: Report
System: The UNT Digital Library
Microwave Ion Source and Beam Injection for an Accelerator-drivenNeutron Source (open access)

Microwave Ion Source and Beam Injection for an Accelerator-drivenNeutron Source

An over-dense microwave driven ion source capable ofproducing deuterium (or hydrogen) beams at 100-200 mA/cm2 and with atomicfraction>90 percent was designed and tested with an electrostaticlow energy beam transport section (LEBT). This ion source wasincorporatedinto the design of an Accelerator Driven Neutron Source(ADNS). The other key components in the ADNS include a 6 MeV RFQaccelerator, a beam bending and scanning system, and a deuterium gastarget. In this design a 40 mA D+ beam is produced from a 6 mm diameteraperture using a 60 kV extraction voltage. The LEBT section consists of 5electrodes arranged to form 2 Einzel lenses that focus the beam into theRFQ entrance. To create the ECR condition, 2 induction coils are used tocreate ~; 875 Gauss on axis inside the source chamber. To prevent HVbreakdown in the LEBT a magnetic field clamp is necessary to minimize thefield in this region. Matching of the microwave power from the waveguideto the plasma is done by an autotuner. We observed significantimprovement of the beam quality after installing a boron nitride linerinside the ion source. The measured emittance data are compared withPBGUNS simulations.
Date: February 15, 2007
Creator: Vainionpaa, J. H.; Gough, R.; Hoff, M.; Kwan, J. W.; Ludewigt, B. A.; Regis, M. J. et al.
Object Type: Article
System: The UNT Digital Library
CH-TRU Waste Content Codes (CH-TRUCON) (open access)

CH-TRU Waste Content Codes (CH-TRUCON)

The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container. Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 …
Date: February 15, 2007
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library
Single and Triple Differential Cross Sections for DoublePhotoionization of H- (open access)

Single and Triple Differential Cross Sections for DoublePhotoionization of H-

The hydride anion H- would not be bound in the absence ofelectron correlation. Electron correlation drives the doublephotoionization process and, thus should impact double photoionizationresults most strongly for H-. We present fully differential crosssections for the three-body breakup of H- by single photon absorption.The absolute triple-differential and single-differential cross sectionswere yielded by ab initio calculations making use of exterior complexscaling within a discrete variable representation partialwave basis.Results calculated at photon energies of 18eV and 30eV are compared withreported cross sections for helium calculated at 20eV above the doubleionization threshold. These comparisons show a clear signature of initialstate correlation that differentiate the He and H- cases.
Date: February 15, 2007
Creator: Yip, Frank L.; Horner, Daniel A.; McCurdy, C. William & Rescigno,Thomas N.
Object Type: Article
System: The UNT Digital Library