Absolute Determination of Charge-Coupled Device Quantum Detection Efficiency Using Si K-Edge X-Ray Absorption Fine Structure (open access)

Absolute Determination of Charge-Coupled Device Quantum Detection Efficiency Using Si K-Edge X-Ray Absorption Fine Structure

We report a method to determine the quantum detection efficiency and the absorbing layers on a front-illuminated charge-coupled device (CCD). The CCD under study, as part of a crystal spectrometer, measures intense continuum x-ray emission from a picosecond laser-produced plasma and spectrally resolves the Si K-edge x-ray absorption fine structure features due to the electrode gate structure of the device. The CCD response across the Si K-edge shows a large discontinuity as well as a number of oscillations that are identified individually and uniquely from Si, SiO{sub 2}, and Si{sub 3}N{sub 4} layers. From the spectral analysis of the structure and K-edge discontinuity, the active layer thickness and the different absorbing layers thickness can be determined precisely. A precise CCD detection model from 0.2-10 keV can be deduced from this highly sensitive technique.
Date: May 6, 2012
Creator: Dunn, J. & Steel, A. B.
Object Type: Article
System: The UNT Digital Library
ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #46000619120 (open access)

ANALYSIS OF HARRELL MONOSODIUM TITANATE LOT #46000619120

Monosodium titanate (MST) for use in the Actinide Removal Process (ARP) must be qualified and verified in advance. A single qualification sample for each batch of material is sent to SRNL for analysis, as well as a statistical sampling of verification samples. The Harrell Industries Lot #46000619120 qualification and the 13 verification samples met each of the selected specification requirements that were tested and, consequently, the material is acceptable for use in the ARP process.
Date: September 6, 2012
Creator: Taylor-Pashow, K.
Object Type: Report
System: The UNT Digital Library
Assembly and Packaging of a Wireless, Chronically-Implantable Neural Prosthetic Device (open access)

Assembly and Packaging of a Wireless, Chronically-Implantable Neural Prosthetic Device

None
Date: August 6, 2012
Creator: Shah, K G; DeLima, T; Benett, W; Felix, S; Sheth, H; Tolosa, V et al.
Object Type: Article
System: The UNT Digital Library
Assessment of an ORION-based experimental platform for measuring the opacity of high-temperature and high-density plasma (open access)

Assessment of an ORION-based experimental platform for measuring the opacity of high-temperature and high-density plasma

None
Date: September 6, 2012
Creator: Beiersdorfer, P
Object Type: Report
System: The UNT Digital Library
BALLISTICS TESTING OF THE 9977 SHIPPING PACKAGE FOR STORAGE APPLICATIONS (open access)

BALLISTICS TESTING OF THE 9977 SHIPPING PACKAGE FOR STORAGE APPLICATIONS

Radioactive materials are stored in a variety of locations throughout the DOE complex. At the Savannah River Site (SRS), materials are stored within dedicated facilities. Each of those facilities has a documented safety analysis (DSA) that describes accidents that the facility and the materials within it may encounter. Facilities at the SRS are planning on utilizing the certified Model 9977 Shipping Package as a long term storage package and one of these facilities required ballistics testing. Specifically, in order to meet the facility DSA, the radioactive materials (RAM) must be contained within the storage package after impact by a .223 caliber round. In order to qualify the Model 9977 Shipping Package for storage in this location, the package had to be tested under these conditions. Over the past two years, the Model 9977 Shipping Package has been subjected to a series of ballistics tests. The purpose of the testing was to determine if the 9977 would be suitable for use as a storage package at a Savannah River Site facility. The facility requirements are that the package must not release any of its contents following the impact in its most vulnerable location by a .223 caliber round. A package, assembled …
Date: June 6, 2012
Creator: Loftin, B.; Abramczyk, G. & Koenig, R.
Object Type: Article
System: The UNT Digital Library
Biomass Gas Cleanup Using a Therminator (open access)

Biomass Gas Cleanup Using a Therminator

The objective of the project is to develop and demonstrate a novel fluidized-bed process module called a “Therminator” to simultaneously destroy and/or remove tar, NH3 and H2S from raw syngas produced by a fluidized-bed biomass gasifier. The raw syngas contains as much as 10 g/m3 of tar, 4,000 ppmv of NH3 and 100 ppmv of H2S. The goal of the Therminator module would be to use promising regenerable catalysts developed for removing tar, ammonia, and H2S down to low levels (around 10 ppm). Tars are cracked to a non-condensable gas and coke that would deposit on the acid catalyst. We will deposit coke, much like a fluid catalytic cracker (FCC) in a petroleum refinery. The deposited coke fouls the catalyst, much like FCC, but the coke would be burned off in the regenerator and the regenerated catalyst would be returned to the cracker. The rapid circulation between the cracker and regenerator would ensure the availability of the required amount of regenerated catalyst to accomplish our goal. Also, by removing sulfur down to less than 10 ppmv, NH3 decomposition would also be possible in the cracker at 600-700°C. In the cracker, tar decomposes and lays down coke on the acid sites …
Date: March 6, 2012
Creator: Dayton, David C.; Kataria, Atish & Gupta, Rabhubir
Object Type: Report
System: The UNT Digital Library
Booster Synchrotron RF System Upgrade for SPEAR3 (open access)

Booster Synchrotron RF System Upgrade for SPEAR3

Recent progress at the SPEAR3 includes the increase in stored current from 100 mA to 200 mA and top-off injection to allow beamlines to stay open during injection. Presently the booster injects 3.0 GeV beam to SPEAR3 three times a day. The stored beam decays to about 150 mA between the injections. The growing user demands are to increase the stored current to the design value of 500 mA, and to maintain it at a constant value within a percent or so. To achieve this goal the booster must inject once every few minutes. For improved injection efficiency, all RF systems at the linac, booster and SPEAR3 need to be phase-locked. The present booster RF system is basically a copy of the SPEAR2 RF system with 358.5 MHz and 40 kW peak RF power driving a 5-cell RF cavity for 1.0 MV gap voltage. These requirements entail a booster RF system upgrade to a scaled down version of the SPEAR3 RF system of 476.3 MHz with 1.2 MW cw klystron output power capabilities. We will analyze each subsystem option for their merits within budgetary and geometric space constraints. A substantial portion of the system will come from the decommissioned PEP-II …
Date: July 6, 2012
Creator: Park, Sanghyun & Corbett, Jeff
Object Type: Article
System: The UNT Digital Library
Bunch Length Measurements With Laser/SR Cross-Correlation (open access)

Bunch Length Measurements With Laser/SR Cross-Correlation

By operating SPEAR3 in low-{alpha} mode the storage ring can generate synchrotron radiation pulses of order 1ps. Applications include pump-probe x-ray science and the production of THz radiation in the CSR regime. Measurements of the bunch length are difficult, however, because the light intensity is low and streak cameras typically provide resolution of only a few ps. Tests are now underway to resolve the short bunch length using cross-correlation between a 60-fs Ti:Sapphire laser and the visible SR beam in a BBO crystal. In this paper we report on the experimental setup, preliminary measurements and prospects for further improvement.
Date: July 6, 2012
Creator: Miller, Timothy; Daranciang, Dan; Lindenberg, Aaron; Corbett, Jeff; Fisher, Alan; Goodfellow, John et al.
Object Type: Article
System: The UNT Digital Library
Calculation of Kinetics Parameters for the NBSR (open access)

Calculation of Kinetics Parameters for the NBSR

The delayed neutron fraction and prompt neutron lifetime have been calculated at different times in the fuel cycle for the NBSR when fueled with both high-enriched uranium (HEU) and low-enriched uranium (LEU) fuel. The best-estimate values for both the delayed neutron fraction and the prompt neutron lifetime are the result of calculations using MCNP5-1.60 with the most recent ENDFB-VII evaluations. The best-estimate values for the total delayed neutron fraction from fission products are 0.00665 and 0.00661 for the HEU fueled core at startup and end-of-cycle, respectively. For the LEU fuel the best estimate values are 0.00650 and 0.00648 at startup and end-of-cycle, respectively. The present recommendations for the delayed neutron fractions from fission products are smaller than the value reported previously of 0.00726 for the HEU fuel. The best-estimate values for the contribution from photoneutrons will remain as 0.000316, independent of the fuel or time in the cycle.The values of the prompt neutron lifetime as calculated with MCNP5-1.60 are compared to values calculated with two other independent methods and the results are in reasonable agreement with each other. The recommended, conservative values of the neutron lifetime for the HEU fuel are 650 {micro}s and 750 {micro}s for the startup and …
Date: March 6, 2012
Creator: L., Hanson A. & D., Diamond
Object Type: Report
System: The UNT Digital Library
Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar (open access)

Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different …
Date: April 6, 2012
Creator: Gandini, Paolo
Object Type: Article
System: The UNT Digital Library
Coherence Properties of Individual Femtosecond Pulses of an X-ray Free-Electron Laser (open access)

Coherence Properties of Individual Femtosecond Pulses of an X-ray Free-Electron Laser

Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in 'diffract-and-destroy' mode. We determined a coherence length of 17 {micro}m in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.
Date: June 6, 2012
Creator: Vartanyants, I. A.; Singer, A.; Mancuso, A. P.; Yefanov, O. M.; Sakdinawat, A.; Liu, Y. et al.
Object Type: Article
System: The UNT Digital Library
Compositional and Gate Tuning of the Interfacial Conductivity in LaAlO3/LaTiO3/SrTiO3 Heterostructures (open access)

Compositional and Gate Tuning of the Interfacial Conductivity in LaAlO3/LaTiO3/SrTiO3 Heterostructures

None
Date: December 6, 2012
Creator: Hosoda, Masayuki; Bell, Christopher; Hikita, Yasuyuki & Hwang, Harold Y.
Object Type: Article
System: The UNT Digital Library
Constraining PCP Violating Varying Alpha Theory through Laboratory Experiments (open access)

Constraining PCP Violating Varying Alpha Theory through Laboratory Experiments

In this report we have studied the implication of a parity and charge-parity (PCP) violating interaction in varying alpha theory. Due to this interaction, the state of photon polarization can change when it passes through a strong background magnetic field. We have calculated the optical rotation and ellipticity of the plane of polarization of an electromagnetic wave and tested our results against different laboratory experiments. Our model contains a PCP violating parameter {beta} and a scale of alpha variation {omega}. By analyzing the laboratory experimental data, we found the most stringent constraints on our model parameters to be 1 {le} {omega} {le} 10{sup 13} GeV{sup 2} and -0.5 {le} {beta} {le} 0.5. We also found that with the existing experimental input parameters it is very difficult to detect the ellipticity in the near future.
Date: June 6, 2012
Creator: Maity, Debaprasad; /NCTS, Taipei /Taiwan, Natl. Taiwan U.; Chen, Pisin & /NCTS, Taipei /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC
Object Type: Article
System: The UNT Digital Library
Controlling the Actuation Rate of Low Density Shape Memory Polymer Foams in Water (open access)

Controlling the Actuation Rate of Low Density Shape Memory Polymer Foams in Water

None
Date: July 6, 2012
Creator: Singhal, P.; Boyle, T.; Infanger, S.; Letts, S.; Small, W.; Maitland, D. J. et al.
Object Type: Article
System: The UNT Digital Library
Cosmological Imprints of a Generalized Chaplygin Gas Model for the Early Universe (open access)

Cosmological Imprints of a Generalized Chaplygin Gas Model for the Early Universe

We propose a phenomenological model for the early universe where there is a smooth transition between an early quintessence phase and a radiation-dominated era. The matter content is modeled by an appropriately modified Chaplygin gas for the early universe. We constrain the model observationally by mapping the primordial power spectrum of the scalar perturbations to the latest data of WMAP7. We compute as well the spectrum of the primordial gravitational waves as would be measured today. We show that the high frequencies region of the spectrum depends on the free parameter of the model and most importantly this region of the spectrum can be within the reach of future gravitational waves detectors.
Date: June 6, 2012
Creator: Bouhmadi-Lopez, Mariam; /Lisbon, CENTRA; Chen, Pisin; /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC; Liu, Yen-Wei & /Taiwan, Natl. Taiwan U.
Object Type: Article
System: The UNT Digital Library
CSR in the SuperKEKB Damping Ring (open access)

CSR in the SuperKEKB Damping Ring

Coherent synchrotron radiation (CSR) is generated when a bunched beam traverses a dipole magnet or a wiggler/undulator. It can degrade the beam quality in both storage rings and linacs through enhancing the beam energy spread and lengthening the bunch length, even cause single-bunch microwave instabilities. Using several methods, CSR impedances in the positron damping ring (DR) of the SuperKEKB which is under design were calculated. From the impedances due to CSR, resistive wall and various vacuum components, quasi-Green function wake potentials were constructed and used in simulations of Particle-In-Cell (PIC) tracking. We present the CSR related results in this paper.
Date: July 6, 2012
Creator: Zhou, Demin; Abe, Tetsuo; Ikeda, Hitomi; Kikuchi, Mitsuo; Ohmi, Kazuhito; Oide, Katsunobu et al.
Object Type: Article
System: The UNT Digital Library
Dark Matter Searches with Cherenkov Telescopes: Nearby Dwarf Galaxies or Local Galaxy Clusters? (open access)

Dark Matter Searches with Cherenkov Telescopes: Nearby Dwarf Galaxies or Local Galaxy Clusters?

In this paper, we compare dwarf galaxies and galaxy clusters in order to elucidate which object class is the best target for gamma-ray DM searches with imaging atmospheric Cherenkov telescopes (IACTs). We have built a mixed dwarfs+clusters sample containing some of the most promising nearby dwarf galaxies (Draco, Ursa Minor, Wilman 1 and Segue 1) and local galaxy clusters (Perseus, Coma, Ophiuchus, Virgo, Fornax, NGC 5813 and NGC 5846), and then compute their DM annihilation flux profiles by making use of the latest modeling of their DM density profiles. We also include in our calculations the effect of DM substructure. Willman 1 appears as the best candidate in the sample. However, its mass modeling is still rather uncertain, so probably other candidates with less uncertainties and quite similar fluxes, namely Ursa Minor and Segue 1, might be better options. As for galaxy clusters, Virgo represents the one with the highest flux. However, its large spatial extension can be a serious handicap for IACT observations and posterior data analysis. Yet, other local galaxy cluster candidates with more moderate emission regions, such as Perseus, may represent good alternatives. After comparing dwarfs and clusters, we found that the former exhibit annihilation flux profiles …
Date: June 6, 2012
Creator: Sanchez-Conde, Miguel A.; Cannoni, Mirco; Zandanel, Fabio; Gomez, Mario E. & Prada, Francisco
Object Type: Article
System: The UNT Digital Library
Data Summary Report for Hanford Site Coal Ash Characterization (open access)

Data Summary Report for Hanford Site Coal Ash Characterization

The purpose of this report is to present data and findings from sampling and analysis of five distinct areas of coal ash within the Hanford Site River Corridor
Date: March 6, 2012
Creator: Sulloway, H. M.
Object Type: Report
System: The UNT Digital Library
Design and Analysis of the ITER Vertical Stability Coils (open access)

Design and Analysis of the ITER Vertical Stability Coils

The ITER vertical stability (VS) coils have been developed through the preliminary design phase by Princeton Plasma Physics Laboratory (PPPL). Final design, prototyping and construction will be carried out by the Chinese Participant Team contributing lab, Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). The VS coils are a part of the in-vessel coil systems which include edge localized mode (ELM) coils as well as the VS coils. An overview of the ELM coils is provided in another paper at this conference. 15 The VS design employs four turns of stainless steel jacketed mineral insulated copper (SSMIC) conductors The mineral insulation is Magnesium Oxide (MgO). Joule and nuclear heat is removed by water flowing at 3 m/s through the hollow copper conductor. A key element in the design is that slightly elevated temperatures in the conductor and its support spine during operation impose compressive stresses that mitigate fatigue damage. Away from joints, and break-outs, conductor thermal stresses are low because of the axisymmetry of the winding (there are no corner bends as in the ELM coils).The 120 degree segment joint, and break-out or terminal regions are designed with similar but imperfect constraint compared with the ring coil portion of …
Date: September 6, 2012
Creator: Peter H. Titus, et. al.
Object Type: Report
System: The UNT Digital Library
Design and implementation of high magnification framing camera for NIF "ARIANE Light" (open access)

Design and implementation of high magnification framing camera for NIF "ARIANE Light"

None
Date: August 6, 2012
Creator: Ayers, M J; Felker, B; Smalyuk, V; Izumi, N; Piston, K; Holder, J et al.
Object Type: Article
System: The UNT Digital Library
Design of Accelerator Online Simulator Server Using Structured Data (open access)

Design of Accelerator Online Simulator Server Using Structured Data

Model based control plays an important role for a modern accelerator during beam commissioning, beam study, and even daily operation. With a realistic model, beam behaviour can be predicted and therefore effectively controlled. The approach used by most current high level application environments is to use a built-in simulation engine and feed a realistic model into that simulation engine. Instead of this traditional monolithic structure, a new approach using a client-server architecture is under development. An on-line simulator server is accessed via network accessible structured data. With this approach, a user can easily access multiple simulation codes. This paper describes the design, implementation, and current status of PVData, which defines the structured data, and PVAccess, which provides network access to the structured data.
Date: July 6, 2012
Creator: Shen, Guobao; /Brookhaven; Chu, Chungming; /SLAC; Wu, Juhao; /SLAC et al.
Object Type: Article
System: The UNT Digital Library
Determining mutant spectra of three RNA viral samples using ultra-deep sequencing (open access)

Determining mutant spectra of three RNA viral samples using ultra-deep sequencing

RNA viruses have extremely high mutation rates that enable the virus to adapt to new host environments and even jump from one species to another. As part of a viral transmission study, three viral samples collected from naturally infected animals were sequenced using Illumina paired-end technology at ultra-deep coverage. In order to determine the mutant spectra within the viral quasispecies, it is critical to understand the sequencing error rates and control for false positive calls of viral variants (point mutantations). I will estimate the sequencing error rate from two control sequences and characterize the mutant spectra in the natural samples with this error rate.
Date: June 6, 2012
Creator: Chen, H
Object Type: Report
System: The UNT Digital Library
Development of a Steady State Simulation Code for Klystron Amplifiers (open access)

Development of a Steady State Simulation Code for Klystron Amplifiers

None
Date: December 6, 2012
Creator: Marrelli, C.; Spataro, B.; Migliorati, M.; Mostacci, A.; Palumbo, L. & Tantawi, S.G.
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT OF A TAMPER RESISTANT/INDICATING AEROSOL COLLECTION SYSTEM FOR ENVIRONMENTAL SAMPLING AT BULK HANDLING FACILITIES (open access)

DEVELOPMENT OF A TAMPER RESISTANT/INDICATING AEROSOL COLLECTION SYSTEM FOR ENVIRONMENTAL SAMPLING AT BULK HANDLING FACILITIES

Environmental sampling has become a key component of International Atomic Energy Agency (IAEA) safeguards approaches since its approval for use in 1996. Environmental sampling supports the IAEA's mission of drawing conclusions concerning the absence of undeclared nuclear material or nuclear activities in a Nation State. Swipe sampling is the most commonly used method for the collection of environmental samples from bulk handling facilities. However, augmenting swipe samples with an air monitoring system, which could continuously draw samples from the environment of bulk handling facilities, could improve the possibility of the detection of undeclared activities. Continuous sampling offers the opportunity to collect airborne materials before they settle onto surfaces which can be decontaminated, taken into existing duct work, filtered by plant ventilation, or escape via alternate pathways (i.e. drains, doors). Researchers at the Savannah River National Laboratory and Oak Ridge National Laboratory have been working to further develop an aerosol collection technology that could be installed at IAEA safeguarded bulk handling facilities. The addition of this technology may reduce the number of IAEA inspector visits required to effectively collect samples. The principal sample collection device is a patented Aerosol Contaminant Extractor (ACE) which utilizes electrostatic precipitation principles to deposit particulates onto …
Date: June 6, 2012
Creator: Sexton, L.
Object Type: Article
System: The UNT Digital Library