High-brightness Electron Beam Evolution Following Laser-based Cleaning of a Photocathode (open access)

High-brightness Electron Beam Evolution Following Laser-based Cleaning of a Photocathode

None
Date: December 4, 2012
Creator: Zhou, F.; Brachmann, A.; Decker, F -J.; Emma, P.; Gilevich, S.; Iverson, R. et al.
Object Type: Article
System: The UNT Digital Library
REACTIONS OF SODIUM PEROXIDE WITH COMPONENTS OF LEGACY PLUTONIUM MATERIALS (open access)

REACTIONS OF SODIUM PEROXIDE WITH COMPONENTS OF LEGACY PLUTONIUM MATERIALS

Plutonium oxide (PuO{sub 2}) calcined at >900 C resists dissolution in nitric acid (HNO{sub 3})-potassium fluoride (KF) solutions, a common method for their dissolution. The Savannah River National Laboratory (SRNL) has developed an alternate method for large samples of PuO{sub 2}-bearing materials using sodium peroxide (Na{sub 2}O{sub 2}) fusion as a pretreatment. The products of the reaction between Na{sub 2}O{sub 2} and PuO{sub 2} have been reported in the literature. As part of the SRNL development effort, additional data about the reaction between Na{sub 2}O{sub 2} and PuO{sub 2} were required. Also needed were data concerning the reaction of Na{sub 2}O{sub 2} with other components that may be present in the feed materials. Sodium peroxide was reacted with aluminum metal (Al), beryllium metal (Be), graphite, potassium chloride (KCl), magnesium chloride (MgCl{sub 2}), and calcium chloride (CaCl{sub 2}). The paper reports and discusses the reaction products of these and related compounds with Na{sub 2}O{sub 2}.
Date: October 4, 2011
Creator: Pierce, R.; Missimer, D. & Crowder, M.
Object Type: Article
System: The UNT Digital Library
Study of Charmless Hadronic B Decays at BaBar (open access)

Study of Charmless Hadronic B Decays at BaBar

None
Date: June 4, 2013
Creator: Gaz, Alessandro
Object Type: Article
System: The UNT Digital Library
Study for ILC Damping Ring at KEKB (open access)

Study for ILC Damping Ring at KEKB

ILC damping ring consists of very low emittance electron and positron storage rings. It is necessary for ILC damping ring to study electron cloud effects in such low emittance positron ring. We propose a low emittance operation of KEKB to study the effects.
Date: November 4, 2011
Creator: Flanagan, J. W.; Fukuma, H.; Kanazawa, K. I.; Koiso, H.; Masuzawa, M.; Ohmi, Kazuhito et al.
Object Type: Article
System: The UNT Digital Library
Reducing Memory Cost of Exact Diagonalization using Singular Value Decomposition (open access)

Reducing Memory Cost of Exact Diagonalization using Singular Value Decomposition

We present a modified Lanczos algorithm to diagonalize lattice Hamiltonians with dramatically reduced memory requirements. The lattice of size N is partitioned into two subclusters. At each iteration the Lanczos vector is projected into a set of n{sub svd} smaller subcluster vectors using singular value decomposition. For low entanglement entropy S{sub ee}, (satisfied by short range Hamiltonians), we expect the truncation error to vanish as exp(-n{sup 1/S{sub ee}}{sub svd}). Convergence is tested for the Heisenberg model on Kagome clusters of up to 36 sites, with no symmetries exploited, using less than 15GB of memory. Generalization to multiple partitioning is discussed.
Date: November 4, 2011
Creator: Weinstein, Marvin; Auerbach, Assa & Chandra, V. Ravi
Object Type: Article
System: The UNT Digital Library
Virtual Scanning Tunneling Microscopy: A Local Spectroscopic Probe of 2D Electron Systems (open access)

Virtual Scanning Tunneling Microscopy: A Local Spectroscopic Probe of 2D Electron Systems

None
Date: November 4, 2011
Creator: Sciambi, A.; Pelliccione, M.; Bank, S.R.; Gossard, A.C. & Goldhaber-Gordon, D.
Object Type: Article
System: The UNT Digital Library
MODELING ANALYSIS FOR GROUT HOPPER WASTE TANK (open access)

MODELING ANALYSIS FOR GROUT HOPPER WASTE TANK

The Saltstone facility at Savannah River Site (SRS) has a grout hopper tank to provide agitator stirring of the Saltstone feed materials. The tank has about 300 gallon capacity to provide a larger working volume for the grout nuclear waste slurry to be held in case of a process upset, and it is equipped with a mechanical agitator, which is intended to keep the grout in motion and agitated so that it won't start to set up. The primary objective of the work was to evaluate the flow performance for mechanical agitators to prevent vortex pull-through for an adequate stirring of the feed materials and to estimate an agitator speed which provides acceptable flow performance with a 45{sup o} pitched four-blade agitator. In addition, the power consumption required for the agitator operation was estimated. The modeling calculations were performed by taking two steps of the Computational Fluid Dynamics (CFD) modeling approach. As a first step, a simple single-stage agitator model with 45{sup o} pitched propeller blades was developed for the initial scoping analysis of the flow pattern behaviors for a range of different operating conditions. Based on the initial phase-1 results, the phase-2 model with a two-stage agitator was developed …
Date: January 4, 2012
Creator: Lee, S.
Object Type: Article
System: The UNT Digital Library
Novel Sorption Enhanced Reaction Process for Simultaneous Production of CO2 and H2 from Synthesis Gas Produced by Coal Gasification (open access)

Novel Sorption Enhanced Reaction Process for Simultaneous Production of CO2 and H2 from Synthesis Gas Produced by Coal Gasification

The goal of this project is to evaluate the extensive feasibility of a novel concept called Thermal Swing Sorption Enhanced Reaction (TSSER) process to simultaneously produce H{sub 2} and CO{sub 2} as a single unit operation in a sorber-reactor. The successful demonstration of the potential feasibility of the TSSER concept implies that it is worth pursuing further development of the idea. This can be done by more extensive evaluation of the basic sorptive properties of the CO{sub 2} chemisorbents at realistic high pressures and by continuing the experimental and theoretical study of the TSSER process. This will allow us to substantiate the assumptions made during the preliminary design and evaluation of the process and firm up the initial conclusions. The task performed under this project consists of (i) retrofitting an existing single column sorption apparatus for measurement of high pressure CO{sub 2} sorption characteristics, (ii) measurement of high pressure CO{sub 2} chemisorption equilibria, kinetics and sorption-desorption column dynamic characteristics under the conditions of thermal swing operation of the TSSER process, (iii) experimental evaluation of the individual steps of the TSSER process (iv) development of extended mathematical model for simulating cyclic continuous operation of TSSER to aid in process scale-up and …
Date: June 4, 2010
Creator: Sircar, Shivaji; Caram, Hugo S.; Jeong, Kwangkook; Beaver, Michael G.; Ni, Fan & Makebe, Agbor Tabi
Object Type: Report
System: The UNT Digital Library
Status of the Linac Coherent Light Source (open access)

Status of the Linac Coherent Light Source

The Linac Coherent Light Source (LCLS) is a free electron laser facility in construction at Stanford Linear Accelerator Center. It is designed to operate in the wavelength range 0.15-1.5 nanometers. At the time of this conference, civil construction of new tunnels and buildings is complete, the necessary modifications to the SLAC linac are complete, and the undulator system and x-ray optics/diagnostics are being installed. The electron gun, 135 MeV injector linac and 250 MeV bunch compressor were commissioned in 2007. Accelerator commissioning activities are presently devoted to the achievement of performance goals for the completed 14 GeV linac.
Date: November 4, 2011
Creator: Galayda, John N.
Object Type: Article
System: The UNT Digital Library
Study on the Mechanical Instability of MICE Coupling Magnets (open access)

Study on the Mechanical Instability of MICE Coupling Magnets

The superconducting coupling solenoid magnet is one of the key equipment in the Muon Ionization Cooling Experiment (MICE). The coil has an inner radius of 750 mm, length of 281 mm and thickness of 104 mm at room temperature. The peak induction in the coil is about 7.3 T with a full current of 210 A. The mechanical disturbances which might cause the instability of the impregnated superconducting magnet involve the frictional motion between conductors and the cracking of impregnated materials. In this paper, the mechanical instability of the superconducting coupling magnet was studied. This paper presents the numerical calculation results of the minimum quench energy (MQE) of the coupling magnet, as well as the dissipated strain energy in the stress concentration region when the epoxy cracks and the frictional energy caused by 'stick-slip' of the conductor based on the bending theory of beam happens. Slip planes are used in the coupling coil and the frictional energy due to 'slow slip' at the interface of the slip planes was also investigated. The dissipated energy was compared with MQE, and the results show that the cracking of epoxy resin in the region of shear stress concentration is the main factor for …
Date: May 4, 2011
Creator: Wang, Li; Pan, Heng; Gou, Xing Long; Wu, Hong; Zheng, Shi Xian & Green, Michael A
Object Type: Article
System: The UNT Digital Library
Optimal alignment of mirror based pentaprisms for scanning deflectometric devices (open access)

Optimal alignment of mirror based pentaprisms for scanning deflectometric devices

In the recent work [Proc. of SPIE 7801, 7801-2/1-12 (2010), Opt. Eng. 50(5) (2011), in press], we have reported on improvement of the Developmental Long Trace Profiler (DLTP), a slope measuring profiler available at the Advanced Light Source Optical Metrology Laboratory, achieved by replacing the bulk pentaprism with a mirror based pentaprism (MBPP). An original experimental procedure for optimal mutual alignment of the MBPP mirrors has been suggested and verified with numerical ray tracing simulations. It has been experimentally shown that the optimally aligned MBPP allows the elimination of systematic errors introduced by inhomogeneity of the optical material and fabrication imperfections of the bulk pentaprism. In the present article, we provide the analytical derivation and verification of easily executed optimal alignment algorithms for two different designs of mirror based pentaprisms. We also provide an analytical description for the mechanism for reduction of the systematic errors introduced by a typical high quality bulk pentaprism. It is also shown that residual misalignments of an MBPP introduce entirely negligible systematic errors in surface slope measurements with scanning deflectometric devices.
Date: March 4, 2011
Creator: Barber, Samuel K.; Geckeler, Ralf D.; Yashchuk, Valeriy V.; Gubarev, Mikhail V.; Buchheim, Jana; Siewert, Frank et al.
Object Type: Article
System: The UNT Digital Library
Behavioral Initiatives for Energy Efficiency (open access)

Behavioral Initiatives for Energy Efficiency

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program around the collection and useage of energy-use data (project title "Large-Scale Energy Reductions through Sensors, Feedback & Information Technology") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: June 4, 2012
Creator: Stanford University
Object Type: Text
System: The UNT Digital Library
Applications of Robust, Radiation Hard AlGaN Optoelectronic Devices in Space Exploration and High Energy Density Physics (open access)

Applications of Robust, Radiation Hard AlGaN Optoelectronic Devices in Space Exploration and High Energy Density Physics

This slide show presents: space exploration applications; high energy density physics applications; UV LED and photodiode radiation hardness; UV LED and photodiode space qualification; UV LED AC charge management; and UV LED satellite payload instruments. A UV LED satellite will be launched 2nd half 2012.
Date: May 4, 2011
Creator: Sun, K.
Object Type: Article
System: The UNT Digital Library
Design and Construction of a Gas Jet Target for RIB Experiements (open access)

Design and Construction of a Gas Jet Target for RIB Experiements

PNNL is now part of the JENSA collaboration to produce a gas jet system for the Facility for Rare Isotope Beams (FRIB). This document is a status report for the gas jet working group to be delivered to the FRIB scientific advisory council (SAC). It briefly describes PNNL’s capability at constructing cost efficient and high detection efficiency HPGe arrays.
Date: February 4, 2011
Creator: Greife, Uwe; Chipps, Kelly A.; Smith, Michael; Bardayan, Dan W.; Pain, Steven D.; Schmitt, Kyle et al.
Object Type: Report
System: The UNT Digital Library
Theoretical & Experimental Studies of Elementary Particles (open access)

Theoretical & Experimental Studies of Elementary Particles

Abstract High energy physics has been one of the signature research programs at the University of Rochester for over 60 years. The group has made leading contributions to experimental discoveries at accelerators and in cosmic rays and has played major roles in developing the theoretical framework that gives us our ``standard model'' of fundamental interactions today. This award from the Department of Energy funded a major portion of that research for more than 20 years. During this time, highlights of the supported work included the discovery of the top quark at the Fermilab Tevatron, the completion of a broad program of physics measurements that verified the electroweak unified theory, the measurement of three generations of neutrino flavor oscillations, and the first observation of a ``Higgs like'' boson at the Large Hadron Collider. The work has resulted in more than 2000 publications over the period of the grant. The principal investigators supported on this grant have been recognized as leaders in the field of elementary particle physics by their peers through numerous awards and leadership positions. Most notable among them is the APS W.K.H. Panofsky Prize awarded to Arie Bodek in 2004, the J.J. Sakurai Prizes awarded to Susumu Okubo and …
Date: October 4, 2012
Creator: McFarland, Kevin
Object Type: Report
System: The UNT Digital Library
UTC Power/Delphi SECA CBS Final Report (open access)

UTC Power/Delphi SECA CBS Final Report

The subject report summarizes the results of solid oxide fuel cell development conducted by UTC Power in conjunction with Delphi Automotive Systems under a cost-share program with from October 2008 through March of 2013. Over that period Delphi Automotive Systems developed a nearly four times larger area solid oxide fuel cell stack capable of operating on pre-reformed natural gas and simulated coal gas with durability demonstrated to 5,000 hours and projected to exceed 10,000 hours. The new stack design was scaled to 40-cell stacks with power output in excess of 6.25kW. Delphi also made significant strides in improving the manufacturability, yield and production cost of these solid oxide fuel cells over the course of the program. Concurrently, UTC Power developed a conceptual design for a 120 MW Integrated Gasification Fuel Cell (IGFC) operating on coal syngas with as high as 57% Higher Heating Value (HHV) efficiency as a measure of the feasibility of the technology. Subsequently a 400 kW on-site system preliminary design with 55% Lower Heating Value (LHV) efficiency operating on natural gas was down-selected from eighteen candidate designs. That design was used as the basis for a 25kW breadboard power plant incorporating four Delphi cell stacks that was …
Date: April 4, 2013
Creator: Gorman, Michael & Kerr, Rich
Object Type: Report
System: The UNT Digital Library
Technical Needs for Enhancing Risk Monitors with Equipment Condition Assessment for Advanced Small Modular Reactors (open access)

Technical Needs for Enhancing Risk Monitors with Equipment Condition Assessment for Advanced Small Modular Reactors

Advanced small modular reactors (aSMRs) can provide the United States with a safe, sustainable, and carbon-neutral energy source. The controllable day-to-day costs of aSMRs are expected to be dominated by operation and maintenance costs. Health and condition assessment coupled with online risk monitors can potentially enhance affordability of aSMRs through optimized operational planning and maintenance scheduling. Currently deployed risk monitors are an extension of probabilistic risk assessment (PRA). For complex engineered systems like nuclear power plants, PRA systematically combines event likelihoods and the probability of failure (POF) of key components, so that when combined with the magnitude of possible adverse consequences to determine risk. Traditional PRA uses population-based POF information to estimate the average plant risk over time. Currently, most nuclear power plants have a PRA that reflects the as-operated, as-modified plant; this model is updated periodically, typically once a year. Risk monitors expand on living PRA by incorporating changes in the day-by-day plant operation and configuration (e.g., changes in equipment availability, operating regime, environmental conditions). However, population-based POF (or population- and time-based POF) is still used to populate fault trees. Health monitoring techniques can be used to establish condition indicators and monitoring capabilities that indicate the component-specific POF at …
Date: April 4, 2013
Creator: Coble, Jamie B.; Coles, Garill A.; Ramuhalli, Pradeep; Meyer, Ryan M.; Berglin, Eric J.; Wootan, David W. et al.
Object Type: Report
System: The UNT Digital Library
Analyses of U metal for H, C and O (open access)

Analyses of U metal for H, C and O

None
Date: December 4, 2012
Creator: Weber, P K; Matzel, J E & Hutcheon, I D
Object Type: Report
System: The UNT Digital Library
Efficient Power Conversion (open access)

Efficient Power Conversion

Advanced Research Projects Agency-Energy project sheet summarizing general information about the 14 projects that are a part of the Agile Delivery of Electrical Power Technology (ADEPT) program including project goals, innovation needs, and potential impacts.
Date: June 4, 2012
Creator: United States. Advanced Research Projects Agency-Energy.
Object Type: Text
System: The UNT Digital Library
FY12 Report: Meteorological Observations for Renewable Energy Applications at Site 300 (open access)

FY12 Report: Meteorological Observations for Renewable Energy Applications at Site 300

None
Date: October 4, 2012
Creator: Wharton, S; Alai, M; Gellner, C & Meyers, K
Object Type: Report
System: The UNT Digital Library
Accelerating the Payment of PACE Assessments By Mark Zimring and Merrian Fulle (open access)

Accelerating the Payment of PACE Assessments By Mark Zimring and Merrian Fulle

The 'acceleration' of land-secured assessments allows municipalities to declare the entire value (not just the late payments) of a property owner's outstanding balance payable if a default occurs. State laws vary on whether acceleration is required, permitted, or prohibited. Acceleration can be attractive to bond investors because it strips out non-performing assessments, and may avoid delays in debt service payments to investors. The risk that non-acceleration will negatively impact bond investors is a particular issue in states without a process for rapidly resolving defaults. However, acceleration may also increase the risk to mortgage holders, as the full amount of the outstanding assessment becomes due and traditionally has priority over other lien holders. Acceleration also places a greater burden on the property owner.
Date: May 4, 2010
Creator: Zimring, Mark & Fuller, Merrian
Object Type: Report
System: The UNT Digital Library
Stockpile Stewardship and the National Ignition Facility (open access)

Stockpile Stewardship and the National Ignition Facility

The National Ignition Facility (NIF), the world's most energetic laser system, is operational at Lawrence Livermore National Laboratory (LLNL). Since the completion of the construction project in March 2009, NIF has completed nearly 150 target experiments for the National Ignition Campaign (NIC), High Energy Density Stewardship Science (HEDSS) in the areas of radiation transport, material dynamics at high pressure in the solid state, as well as fundamental science and other national security missions. NIF capabilities and infrastructure are in place to support all of its missions with over 50 X-ray, optical and nuclear diagnostic systems and the ability to shoot cryogenic targets and DT layered capsules. NIF is now qualified for use of tritium and other special materials as well as to perform high yield experiments and classified experiments. DT implosions with record indirect-drive neutron yield of 4.5 x 10{sup 14} neutrons have been achieved. A series of 43 experiments were successfully executed over a 27-day period, demonstrating the ability to perform precise experiments in new regimes of interest to HEDSS. This talk will provide an update of the progress on the NIF capabilities, NIC accomplishments, as well as HEDSS and fundamental science experimental results and an update of the …
Date: January 4, 2012
Creator: Moses, E.
Object Type: Article
System: The UNT Digital Library
Development and Demonstration of an Innovative Thermal Energy Storage System for Baseload Power Generation (open access)

Development and Demonstration of an Innovative Thermal Energy Storage System for Baseload Power Generation

The objective of this project is to research and develop a thermal energy storage system (operating range 3000C – 450 0C ) based on encapsulated phase change materials (PCM) that can meet the utility-scale base-load concentrated solar power plant requirements at much lower system costs compared to the existing thermal energy storage (TES) concepts. The major focus of this program is to develop suitable encapsulation methods for existing low-cost phase change materials that would provide a cost effective and reliable solution for thermal energy storage to be integrated in solar thermal power plants. This project proposes a TES system concept that will allow for an increase of the capacity factor of the present CSP technologies to 75% or greater and reduce the cost to less than $20/kWht.
Date: September 4, 2012
Creator: Goswami, D. Y.
Object Type: Report
System: The UNT Digital Library
PLUTONIUM SOLUBILITY IN HIGH-LEVEL WASTE ALKALI BOROSILICATE GLASS (open access)

PLUTONIUM SOLUBILITY IN HIGH-LEVEL WASTE ALKALI BOROSILICATE GLASS

The solubility of plutonium in a Sludge Batch 6 (SB6) reference glass and the effect of incorporation of Pu in the glass on specific glass properties were evaluated. A Pu loading of 1 wt % in glass was studied. Prior to actual plutonium glass testing, surrogate testing (using Hf as a surrogate for Pu) was conducted to evaluate the homogeneity of significant quantities of Hf (Pu) in the glass, determine the most appropriate methods to evaluate homogeneity for Pu glass testing, and to evaluate the impact of Hf loading in the glass on select glass properties. Surrogate testing was conducted using Hf to represent between 0 and 1 wt % Pu in glass on an equivalent molar basis. A Pu loading of 1 wt % in glass translated to {approx}18 kg Pu per Defense Waste Processing Facility (DWPF) canister, or about 10X the current allowed limit per the Waste Acceptance Product Specifications (2500 g/m{sup 3} of glass or about 1700 g/canister) and about 30X the current allowable concentration based on the fissile material concentration limit referenced in the Yucca Mountain Project License Application (897 g/m{sup 3}3 of glass or about 600 g Pu/canister). Based on historical process throughput data, this …
Date: January 4, 2011
Creator: Marra, J.; Crawford, C.; Fox, K. & Bibler, N.
Object Type: Report
System: The UNT Digital Library