Measurement of the Inelastic Proton-Proton Cross-Section at sqrt{s}=7 TeV with the ATLAS Detector (open access)

Measurement of the Inelastic Proton-Proton Cross-Section at sqrt{s}=7 TeV with the ATLAS Detector

None
Date: June 5, 2013
Creator: Aad, Georges
System: The UNT Digital Library
RECERTIFICATION OF THE MODEL 9977 RADIOACTIVE MATERIAL PACKAGING (open access)

RECERTIFICATION OF THE MODEL 9977 RADIOACTIVE MATERIAL PACKAGING

The Model 9977 Packaging was initially issued a Certificate of Compliance (CoC) by the Department of Energy’s Office of Environmental Management (DOE-EM) for the transportation of radioactive material (RAM) in the Fall of 2007. This first CoC was for a single radioactive material and two packing configurations. In the five years since that time, seven Addendums have been written to the Safety Analysis Report for Packaging (SARP) and five Letter Amendments have been written that have authorized either new RAM contents or packing configurations, or both. This paper will discuss the process of updating the 9977 SARP to include all the contents and configurations, including the addition of a new content, and its submittal for recertification.
Date: June 5, 2013
Creator: Abramczyk, G.; Bellamy, S.; Loftin, B. & Nathan, S.
System: The UNT Digital Library
PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS (open access)

PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS

For the transportation of Radioactive Material (RAM) packages, the requirements for the maximum allowed dose rate at the package surface and in its vicinity are given in Title 10 of the Code of Federal Regulations, Section 71.47. The regulations are based on the acceptable dose rates to which the public, workers, and the environment may be exposed. As such, the regulations specify dose rates, rather than quantity of radioactive isotopes and require monitoring to confirm the requirements are met. 10CFR71.47 requires that each package of radioactive materials offered for transportation must be designed and prepared for shipment so that under conditions normally incident to transportation the radiation level does not exceed 2 mSv/h (200 mrem/h) at any point on the external Surface of the package, and the transport index does not exceed 10. Before shipment, the dose rate of the package is determined by measurement, ensuring that it conforms to the regulatory limits, regardless of any analyses. This is the requirement for all certified packagings. This paper discusses the requirements for establishing the dose rates when shipping RAM packages and the precedents for meeting these requirements by measurement.
Date: June 5, 2012
Creator: Abramczyk, G.; Bellamy, S.; Nathan, S. & Loftin, B.
System: The UNT Digital Library
DEVELOPMENT OF THE H1700 SHIPPING PACKAGE (open access)

DEVELOPMENT OF THE H1700 SHIPPING PACKAGE

The H1700 Package is based on the DOE-EM Certified 9977 Packaging. The H1700 will be certified by the Packaging Certification Division of the National Nuclear Security Administration for the shipment of plutonium by air by the United Stated Military both within the United States and internationally. The H1700 is designed to ship radioactive contents in assemblies of Radioisotope Thermoelectric Generators (RTGs) or arrangements of nested food-pack cans. The RTG containers are designed and tested to remain leaktight during transport, handling, and storage; however, their ability to remain leaktight during transport in the H1700 is not credited. This paper discusses the design and special operation of the H1700.
Date: June 5, 2009
Creator: Abramczyk, G.; Loftin, B. & Mann, P.
System: The UNT Digital Library
Plasma Diagnostic Calibration and Characterizations with High Energy X-rays (open access)

Plasma Diagnostic Calibration and Characterizations with High Energy X-rays

National Security Technologies’ High Energy X-ray (HEX) Facility is unique in the U.S. Department of Energy complex. The HEX provides fluorescent X-rays of 5 keV to 100 keV with fluence of 10^5–10^6 photons/cm^2/second at the desired line energy. Low energy lines can be filtered, and both filters and fluorescers can be changed rapidly. We present results of calibrating image plates (sensitivity and modulation transfer function), a Bremsstrahlung spectrometer (stacked filters and image plates), and the National Ignition Facility’s Filter- Fluorescer Experiment (FFLEX) high energy X-ray spectrometer. We also show results of a scintillator light yield and alignment study for a neutron imaging system.
Date: June 5, 2009
Creator: Ali, Zaheer
System: The UNT Digital Library
Radiation-induced segregation and the relationship to physical properties in irradiated austenitic alloys. (open access)

Radiation-induced segregation and the relationship to physical properties in irradiated austenitic alloys.

Radiation-induced changes in composition are studied because these changes can degrade failure of materials irradiated in nuclear reactors. In this work, the effect of alloy composition on radiation-induced segregation, hardening, and void swelling is presented. Five alloys, Fe-18Cr-8Ni, Fe-16Cr-13Ni, Fe-18Cr-40Ni, Fe-16Cr-13Ni+Mo, and Fe-16Cr-13Ni+Mo+P (all compositions in wt. %), were irradiated with 3.2 MeV protons at 400 C to a dose of 0.5 displacements per atom. The change in grain boundary composition was measured using field emission gun scanning transmission electron microscopy and the hardening was measured using Vickers indentation. Void swelling is calculated from the void size distribution measured using transmission electron microscopy. After irradiation, Cr depletes and Ni enriches at grain boundaries. Increasing bulk Ni concentration causes greater Cr depletion and Ni enrichment at grain boundaries. For alloys with 16 Cr, the addition of P reduces the Cr depletion and Ni enrichment. Hardening does not directly correlate with composition, but a framework for isolating the effect of hardening and segregation on cracking is suggested. The amount of void swelling in the irradiated material is shown to correspond inversely with segregation. Those alloys with greater segregation tend to swell less.
Date: June 5, 2002
Creator: Allen, T. R.; Cole, J. I.; Was, G. S. & Kenik, E. A.
System: The UNT Digital Library
Properties of 20% cold-worked 316 stainless steel irradiated at low dose rate. (open access)

Properties of 20% cold-worked 316 stainless steel irradiated at low dose rate.

To assess the effects of long-term, low-dose-rate neutron exposure, tensile, hardness, and fracture properties were measured and microstructural characterization performed on irradiated 20% cold-worked Type 316 stainless steel. Samples were prepared from reactor core components retrieved from the EBR-II reactor following final shutdown. Sample locations were chosen to cover a dose range of 1-56 dpa at temperatures from 371-390 C and dose rates from 0.8-3.3 x 10{sup -7} dpa/s. Irradiation caused hardening, with the ultimate tensile strength (UTS) reaching about 800 MPa near 20 dpa and appearing to saturate at higher doses. The yield strength (YS) follows approximately the same trend as the ultimate tensile strength. At higher dose, the difference between the UTS and YS decreases, suggesting the work-hardening capability of the material is decreasing with increasing dose. The hardness and yield strength increases occur roughly over the same range of dose. While the material retained respectable ductility at 20 dpa, the uniform and total elongation decreased to <1 and <3%, respectively, at 47 dpa. Fracture in the 30 dpa specimen is mainly ductile but with local regions of mixed-mode failure, consisting mainly of dimples and microvoids. The fracture surface of the higher-exposure 47 dpa specimen displays more brittle …
Date: June 5, 2002
Creator: Allen, T. R.; Tsai, H.; Cole, J. I.; Ohta, J.; Dohi, K. & Kusanagi, H.
System: The UNT Digital Library
Analysis of Enriched Uranium and Weapons Plutonium Reloads for PWRs Using BRACC (open access)

Analysis of Enriched Uranium and Weapons Plutonium Reloads for PWRs Using BRACC

Comparisons of the multicycle results demonstrate that the correlation coefficients based on the CASMO3 data were implemented correctly and that the Linear Reactivity Model is acceptably accurate for missed reloads containing both uranium and weapons plutonium fuel. The expanded set of correlation coefficients make BRACC a useful tool for performing multi-cycle in-core fuel management studies of PWR cores containing weapons plutonium.
Date: June 5, 1997
Creator: Alonso, G. & Parish, T. A.
System: The UNT Digital Library
Three-dimensional thermal analysis of a baseline spent fuel repository (open access)

Three-dimensional thermal analysis of a baseline spent fuel repository

A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplaced to yield a 36 kw/acre (8.9 w/m/sup 2/) loading. A unit cell model in an infinite array is used to simplify the problem and provide upper-bound temperatures. Boundary conditions are imposed which allow simulations to 1000 years. Variations studied include a comparison of ventilated and unventilated storage room conditions, emplacement packages with and without air gaps surrounding the canister, and room cool-down scenarios with ventilation following an unventilated state for retrieval purposes. At this low power level ventilating the emplacement room has an immediate cooling influence on the canister and effectively maintains the emplacement room floor near the temperature of the ventilating air. The annular gap separating the canister and sleeve causes the peak temperature of the canister surface to rise by 10/sup 0/F (5.6/sup 0/C) over that from a …
Date: June 5, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
System: The UNT Digital Library
EPSILON HYPERONS IN THE REACTION K- + P -->+ K+ (open access)

EPSILON HYPERONS IN THE REACTION K- + P -->+ K+

None
Date: June 5, 1962
Creator: Alvarez, Luis W.; Berge, J. Peter; Kalbfleisch, George R.; Button-Shafer, Janice; Solmitz, Frank T.; Stevenson, M. Lynn et al.
System: The UNT Digital Library
A korarchaeal genome reveals insights into the evolution of the Archaea (open access)

A korarchaeal genome reveals insights into the evolution of the Archaea

The candidate division Korarchaeota comprises a group of uncultivated microorganisms that, by their small subunit rRNA phylogeny, may have diverged early from the major archaeal phyla Crenarchaeota and Euryarchaeota. Here, we report the initial characterization of a member of the Korarchaeota with the proposed name,"Candidatus Korarchaeum cryptofilum," which exhibits an ultrathin filamentous morphology. To investigate possible ancestral relationships between deep-branching Korarchaeota and other phyla, we used whole-genome shotgun sequencing to construct a complete composite korarchaeal genome from enriched cells. The genome was assembled into a single contig 1.59 Mb in length with a G + C content of 49percent. Of the 1,617 predicted protein-coding genes, 1,382 (85percent) could be assigned to a revised set of archaeal Clusters of Orthologous Groups (COGs). The predicted gene functions suggest that the organism relies on a simple mode of peptide fermentation for carbon and energy and lacks the ability to synthesize de novo purines, CoA, and several other cofactors. Phylogenetic analyses based on conserved single genes and concatenated protein sequences positioned the korarchaeote as a deep archaeal lineage with an apparent affinity to the Crenarchaeota. However, the predicted gene content revealed that several conserved cellular systems, such as cell division, DNA replication, and tRNA …
Date: June 5, 2008
Creator: Anderson, Iain J; Elkins, James G.; Podar, Mircea; Graham, David E.; Makarova, Kira S.; Wolf, Yuri et al.
System: The UNT Digital Library
New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3 (open access)

New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3

The Soudan 1 experiment has obtained additional evidence for underground muons associated with the x-ray pulsar Cygnus X-3. We report the preliminary analysis of data recorded during the October 1985 radio outburst of Cygnus X-3, which show a significant excess of muons for a narrow range of Cygnus X-3 phases.
Date: June 5, 1986
Creator: Ayres, D. S.
System: The UNT Digital Library
DUAL ION EXPOSURE VS. SPLIT-DOSE EXPOSURES IN HUMAN CELL NEOPLASTIC TRANSFORMATION. (open access)

DUAL ION EXPOSURE VS. SPLIT-DOSE EXPOSURES IN HUMAN CELL NEOPLASTIC TRANSFORMATION.

Since radiation fields of space contain many-fold more protons than high atomic number, high energy (HZE) particles, cells in astronaut crews will experience on average several proton hits before an HZE hit. Thus radiation regimes of proton exposure before HZE particle exposure simulate space radiation exposure, and measurement of the frequency of neoplastic transformation of human primary cells to anchorage-independent growth simulates in initial step in cancer induction. Previously our group found that exposure to 20 cGy 1 GeV/n protons followed within about 1 hr by a HZE ion (20 cGy 1 GeV/n Fe or Ti ions) hit gave about a 3-fold increase in transformation frequency ([1]). To provide insight into the H-HZE induced increased transformation frequencies, we asked if split doses of the same ion gave similar increased transformation frequencies. However, the data show that the split dose of 20 cGy plus 20 cGy of either H or HZE ions gave about the same effect as the 40 cGy uninterrupted dose, quite different from the effect of the mixed ion H + HZE irradiation. We also asked if lower proton doses than 20 cGy followed 15 minutes later by 20 cGy of HZE ions gave greater than additive transformation …
Date: June 5, 2006
Creator: BENNETT, P.V.; CUTTER, N.C. & SUTHERLAND, B.M.
System: The UNT Digital Library
A process model of natural attenuation in drainage from a historic mining district (open access)

A process model of natural attenuation in drainage from a historic mining district

A process model was used to better understand the controls on the chemical evolution of drainage in a historic mining district. At the Pecos Mine Operable Unit, New Mexico, drainage near the waste rock pile is acidic (pH varies from 3.0--5.0) and carries high concentrations of Zn, Al, Cu and Pb. As drainage flows toward the Pecos River, pH increases to greater than 7 and heavy metal content decreases. A process model of natural attenuation in this drainage shows the main controls on pH are reaction with a local bedrock that contains limestone, and concurrent mixing with tributary streams. Models that account for both calcite dissolution and mixing reproduce the observed decrease in aqueous metal concentrations with increasing pH. Contaminant concentrations attenuate primarily via two distinct pathways: Al, Cu, Fe and Pb precipitate directly from solution, whereas Zn, Mg, Mn and SO{sub 4} concentrations decrease primarily through dilution. Additionally, Pb adsorbs to precipitating hydroxide surfaces.
Date: June 5, 2000
Creator: BERGER,AMY C.; BETHKE,CRAIG M. & KRUMHANSL,JAMES L.
System: The UNT Digital Library
The Mean and Scatter of the Velocity Dispersion-Optical Richness Relation for MaxBCG Galaxy Clusters (open access)

The Mean and Scatter of the Velocity Dispersion-Optical Richness Relation for MaxBCG Galaxy Clusters

The distribution of galaxies in position and velocity around the centers of galaxy clusters encodes important information about cluster mass and structure. Using the maxBCG galaxy cluster catalog identified from imaging data obtained in the Sloan Digital Sky Survey, we study the BCG--galaxy velocity correlation function. By modeling its non-Gaussianity, we measure the mean and scatter in velocity dispersion at fixed richness. The mean velocity dispersion increases from 202 {+-} 10 km s{sup -1} for small groups to more than 854 {+-} 102 km s{sup -1} for large clusters. We show the scatter to be at most 40.5{+-}3.5%, declining to 14.9{+-}9.4% in the richest bins. We test our methods in the C4 cluster catalog, a spectroscopic cluster catalog produced from the Sloan Digital Sky Survey DR2 spectroscopic sample, and in mock galaxy catalogs constructed from N-body simulations. Our methods are robust, measuring the scatter to well within one-sigma of the true value, and the mean to within 10%, in the mock catalogs. By convolving the scatter in velocity dispersion at fixed richness with the observed richness space density function, we measure the velocity dispersion function of the maxBCG galaxy clusters. Although velocity dispersion and richness do not form a true …
Date: June 5, 2007
Creator: Becker, M. R.; McKay, T. A.; Koester, B.; Wechsler, R. H.; Rozo, E.; Evrard, A. et al.
System: The UNT Digital Library
Simulation of Enhanced-Explosive Devices in Chambers and Tunnels (open access)

Simulation of Enhanced-Explosive Devices in Chambers and Tunnels

Introduction: Shock-dispersed fuel (SDF) explosives use a small chemical charge to disperse a combustible fuel that burns in the post-detonation environment. The energy released in the combustion process has the potential for generating higher pressures and temperatures than conventional explosives. However, the development of these types of novel explosive systems requires a detailed understanding of all of the modes of energy release. Objective: The objective of this project is develop a simulation capability for predicting explosion and combustion phase of SDF charges and apply that capability to quantifying the behavior of these types of explosives. Methodology: We approximate the dynamics of an SDF charge using high Reynolds number, fast chemistry model that effectively captures the thermodynamic behavior of SDF charges and accurately models the key modes of energy release. The overall computational model is combined with Adaptive Mesh Refinement (AMR) , implemented in a parallel adaptive framework suited to the massively parallel computer systems. Results: We have developed a multiphase version of the model and used it to simulate an SDF charge in which the dispersed fuel is aluminum flakes. Flow visualizations show that the combustion field is turbulent for the chamber and tunnel cases studied. During the 3 milli-seconds …
Date: June 5, 2007
Creator: Bell, J B; Kuhl, A L & Beckner, V E
System: The UNT Digital Library
D0 - Anti-D0 Mixing And Search for CP Violation in D0 Decays using T-Odd Correlations at BaBar (open access)

D0 - Anti-D0 Mixing And Search for CP Violation in D0 Decays using T-Odd Correlations at BaBar

None
Date: June 5, 2013
Creator: Bellis, Matthew
System: The UNT Digital Library
Pore compressibility in rocks (open access)

Pore compressibility in rocks

The unjacketed core compressibility in a porous rock is the change in pore volume due to change in pore pressure for constant differential pressure. This parameter affects how the saturated bulk modulus of a rock is related to the drained frame modulus and the pore fluid compressibility. Recent measurements of poroelastic constants and effective medium theories are used to estimate how the pore compressibility depends on effective stress and how uncertainty in the pore compressibility affects uncertainty in Gassmann' equation estimates of the saturated bulk modulus. Results for Berea sandstone and for models of sand-clay mixtures show that the estimate of the change in the saturated bulk modulus due to substitution of different fluids in the rock may differ in size by a factor of two or more if the pore compressibility is approximately equal to the fluid compressibility instead of the grain compressibility. In general, the order of magnitude and sign of the pore compressibility cannot be determined from solid and fluid compressibility information alone.
Date: June 5, 1998
Creator: Berge, P A
System: The UNT Digital Library
Use of Antineutrino Detectors for Nuclear Reactor Safeguards Effectiveness Assessment (open access)

Use of Antineutrino Detectors for Nuclear Reactor Safeguards Effectiveness Assessment

As described in an earlier article [1], important information regarding reactor power and the amount and type of fissile material in reactor cores can be determined by measuring the antineutrino rate and energy spectrum, using a cubic meter scale antineutrino detector at tens of meters standoff from the core. Current International Atomic Energy Agency (IAEA) safeguards techniques do not provide such real-time quantitative information regarding core power levels and isotopic composition. The possible benefits of this approach are several and have been discussed in the earlier article. One key advantage is that the method gives the inspecting agency completely independent access to real-time information on the operational status and fissile content of the core. Furthermore, the unattended and non-intrusive nature of the technology may reduce the monitoring burden on the plant operator, even though more information is being provided than is available within the current IAEA safeguards regime. Here we present a detailed analytical framework for measuring the impact that such a detector might have on IAEA safeguards, if implemented. To perform the analysis, we will use initial data from our operating detector and a standard analysis technique for safeguards regimes, developed at Lawrence Livermore National Laboratory. Because characterization of …
Date: June 5, 2006
Creator: Bernstein, A; Lambert, H E; Elayat, H A; O'Connell, W J; Rexroth, P; Baldwin, G et al.
System: The UNT Digital Library
DOE integrated safeguards and security (DISS) system a nation-wide distributed information system for personnel security (open access)

DOE integrated safeguards and security (DISS) system a nation-wide distributed information system for personnel security

DISS uses secure client-server and relational database technology across open networks to address the problems of security clearance request processing and tracking of security clearances for the Department of energy. The system supports the entire process from data entry by the prospective clearance holders through tracking of all DOE clearances, and use of standard DOE badges in automated access control systems throughout the DOE complex.
Date: June 5, 1997
Creator: Block, B.
System: The UNT Digital Library
Unified Einstein-Virasoro Master Equation in the General Non-Linear Sigma Model (open access)

Unified Einstein-Virasoro Master Equation in the General Non-Linear Sigma Model

The Virasoro master equation (VME) describes the general affine-Virasoro construction $T=L^abJ_aJ_b+iD^a \dif J_a$ in the operator algebra of the WZW model, where $L^ab$ is the inverse inertia tensor and $D^a $ is the improvement vector. In this paper, we generalize this construction to find the general (one-loop) Virasoro construction in the operator algebra of the general non-linear sigma model. The result is a unified Einstein-Virasoro master equation which couples the spacetime spin-two field $L^ab$ to the background fields of the sigma model. For a particular solution $L_G^ab$, the unified system reduces to the canonical stress tensors and conventional Einstein equations of the sigma model, and the system reduces to the general affine-Virasoro construction and the VME when the sigma model is taken to be the WZW action. More generally, the unified system describes a space of conformal field theories which is presumably much larger than the sum of the general affine-Virasoro construction and the sigma model with its canonical stress tensors. We also discuss a number of algebraic and geometrical properties of the system, including its relation to an unsolved problem in the theory of $G$-structures on manifolds with torsion.
Date: June 5, 1996
Creator: Boer, J. de & Halpern, M.B.
System: The UNT Digital Library
10 (micro)m and 5 (micro)m Pinhole-Assisted Point-Projection Backlit Imaging for NIF (open access)

10 (micro)m and 5 (micro)m Pinhole-Assisted Point-Projection Backlit Imaging for NIF

Pinhole-assisted point-projection backlighting with 10{micro}m and 5 {micro}m pinholes placed a small distance of order 1 mm away from the backlighter produces images with large field of view and high resolution. Pinholes placed closely to high-power backlighter sources can vaporize and close due to x-ray driven ablation, thereby limiting the usefulness of this method. A study of streaked 1-D backlit imaging of 25 {micro}m W wires using the OMEGA laser is presented. The pinhole closure timescale for 10 {micro}m pinholes placed 0.45 mm and 1 mm distant from the backlighter is 1.3 ns and 2.2 ns, respectively. Similar timescales for 5 {micro}m pinholes is also presented. Successful wire imaging prior to pinhole closure is clearly demonstrated.
Date: June 5, 2001
Creator: Bullock, A. B.; Landen, O. L. & Bradley, D. K.
System: The UNT Digital Library
Relative x-ray backlighter intensity comparison of ti and ti/sc combination foils driven in double-sided and single-sided laser configuration (open access)

Relative x-ray backlighter intensity comparison of ti and ti/sc combination foils driven in double-sided and single-sided laser configuration

Use of multiple backlighter foils and/or double-sided laser interaction geometry with backlit imaging can result in improved backlighter efficiency. An experimental comparison of backlighter intensity for Ti foils and Ti/Sc combination foils in both the one-sided and double-sided laser-interaction configuration is presented. Spectrally-integrated framing camera images show intensity contributions of front and rear backlighter surfaces for both foil types. Analysis of time-resolved x-ray spectra collected from foil targets show the relative contribution of Ti and Sc 2-1 He-like resonance lines to the total backlighter intensity.
Date: June 5, 2000
Creator: Bullock, A. B.; Landen, O. L. & Bradley, D. K.
System: The UNT Digital Library
Effects of doping on hybridization gapped materials (open access)

Effects of doping on hybridization gapped materials

Doping studies are presented on three materials exhibiting hybridization gaps: Ce{sub 3}Bi{sub 4}Pt{sub 3}, U{sub 3}Sb{sub 4}Pt{sub 3}, and CeRhSb. In the case of trivalent La, Y, or Lu substituting for Ce or U, there is a suppression of the low temperature gap and an increase in the electronic specific heat, {gamma}. In the case of tetravalent Th substitutions for U there is no change in {gamma} and in the case of tetravalent Zr substitution for Ce in CeRhSb, there is an enhanced semiconductor-like behavior in the electrical resistance. These results are discussed in the light of a simple model of hybridization gapped systems. 12 refs., 3 figs.
Date: June 5, 1991
Creator: Canfield, P. C.; Thompson, J. D.; Hundley, M. F.; Lacerda, A. & Fisk, Z.
System: The UNT Digital Library