12,581 Matching Results

Results open in a new window/tab.

1 GeV CW nonscaling FFAG for ADS, and magnet parameters (open access)

1 GeV CW nonscaling FFAG for ADS, and magnet parameters

Multi-MW proton driver capability remains a challenging, critical technology for many core HEP programs, particularly the neutrino ones such as the Muon Collider and Neutrino factory, and for high-profile energy applications such as Accelerator Driven Subcritical Reactors (ADS) and Accelerator Transmutation of Waste for nuclear power and waste management. Work is focused almost exclusively on an SRF linac, as, to date, no re-circulating accelerator can attain the 10-20 MW capability necessary for the nuclear applications. Recently, the concept of isochronous orbits has been explored and developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. Work is progressing on a stable, high-intensity, 1 GeV isochronous FFAG. Initial specifications of novel magnets with the nonlinear radial fields required to support isochronous operation are also reported here.
Date: May 20, 2012
Creator: Johnstone, C.; Meot, F.; Snopok, P. & Weng, W.
Object Type: Article
System: The UNT Digital Library
The 3.8% Medicare Contribution Tax on Unearned Income, Including Real Estate Transactions (open access)

The 3.8% Medicare Contribution Tax on Unearned Income, Including Real Estate Transactions

This reports summarizes a 3.8% Medicare contribution tax on unearned income and provides examples of how it is applied.
Date: May 18, 2012
Creator: Keightley, Mark P.
Object Type: Report
System: The UNT Digital Library
A 3 TeV Muon Collider Lattice Design (open access)

A 3 TeV Muon Collider Lattice Design

A new lattice for 3 TeV c.o.m. energy with {beta}* = 5mm was developed which follows the basic concept of the earlier 1.5 TeV design but uses quad triplets for the final focus in order to keep the maximum magnet strength and aperture close to those in 1.5 TeV case. Another difference is employment of combined-function magnets with the goal to lower heat deposition in magnet cold mass and to eliminate bending field free regions which produce 'hot spots' of neutrino radiation that can be an issue at higher energy. The proposed lattice is shown to satisfy the requirements on luminosity, dynamic aperture and momentum acceptance.
Date: May 1, 2012
Creator: Alexahin, Y. & Gianfelice-Wendt, E.
Object Type: Article
System: The UNT Digital Library
A 4.2 GS/sec. Synchronized Vertical Excitation System for SPS Studies - Steps Toward Wideband Feedback (open access)

A 4.2 GS/sec. Synchronized Vertical Excitation System for SPS Studies - Steps Toward Wideband Feedback

A 4.2 GS/sec. beam excitation system with accelerator synchronization and power stages is described. The system is capable of playing unique samples (32 samples/bunch) for 15,000 turns on selected bunch(es) in the SPS in syn- chronism with the injection and acceleration cycle. The purpose of the system is to excite internal modes of single-bunch vertical motion, and study the bunch dynamics in the presence of developing Electron cloud or TMCI effects. The system includes a synchronized master oscillator, SPS timing functions, an FPGA based arbitrary waveform generator, 4.2 GS/sec. D/A system and four 80W 20-1000 MHz amplifiers driving a tapered stripline pickup/kicker. A software GUI allows specification of various modulation signals, selection of bunches and turns to excite, while a remote control interface allows simple control/monitoring of the RF power stages located in the tunnel. The successful use of this system for SPS MD measurements in 2011 is a vital proof-of-principle for wideband feedback using similar functions to correct the beam motion.
Date: July 10, 2012
Creator: Fox, John
Object Type: Article
System: The UNT Digital Library
4 kW Test of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells (open access)

4 kW Test of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells

A new test stand has been developed at the Idaho National Laboratory for multi-kW testing of solid oxide electrolysis stacks. This test stand will initially be operated at the 4 KW scale. The 4 kW tests will include two 60-cell stacks operating in parallel in a single hot zone. The stacks are internally manifolded with an inverted-U flow pattern and an active area of 100 cm2 per cell. Process gases to and from the two stacks are distributed from common inlet/outlet tubing using a custom base manifold unit that also serves as the bottom current collector plate. The solid oxide cells incorporate a negative-electrode-supported multi-layer design with nickel-zirconia cermet negative electrodes, thin-film yttria-stabilized zirconia electrolytes, and multi-layer lanthanum ferrite-based positive electrodes. Treated metallic interconnects with integral flow channels separate the cells and electrode gases. Sealing is accomplished with compliant mica-glass seals. A spring-loaded test fixture is used for mechanical stack compression. Due to the power level and the large number of cells in the hot zone, process gas flow rates are high and heat recuperation is required to preheat the cold inlet gases upstream of the furnace. Heat recuperation is achieved by means of two inconel tube-in-tube counter-flow heat exchangers. …
Date: June 1, 2012
Creator: O'Brien, J. E.; Zhang, X.; Housley, G. K.; Moore-McAteer, L. & Tao, G.
Object Type: Article
System: The UNT Digital Library
N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops (open access)

N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops

We present the full two-loop four-graviton amplitudes in N = 4, 5, 6 supergravity. These results were obtained using the double-copy structure of gravity, which follows from the recently conjectured color-kinematics duality in gauge theory. The two-loop four-gluon scattering amplitudes in N = 0, 1, 2 supersymmetric gauge theory are a second essential ingredient. The gravity amplitudes have the expected infrared behavior: the two-loop divergences are given in terms of the squares of the corresponding one-loop amplitudes. The finite remainders are presented in a compact form. The finite remainder for N = 8 supergravity is also presented, in a form that utilizes a pure function with a very simple symbol.
Date: February 15, 2012
Creator: Boucher-Veronneau, C. & Dixon, L. J.
Object Type: Article
System: The UNT Digital Library
A 4 to 0.1 nm FEL Based on the SLAC Linac (open access)

A 4 to 0.1 nm FEL Based on the SLAC Linac

The author show that using existing electron gun technology and a high energy linac like the one at SLAC, it is possible to build a Free Electron Laser operating around the 4 nm water window. A modest improvement in the gun performance would further allow to extend the FEL to the 0.1 nm region. Such a system would produce radiation with a brightness many order of magnitude above that of any synchrotron radiation source, existing or under construction, with laser power in the multigawatt region and subpicosecond pulse length.
Date: June 5, 2012
Creator: Pellegrini, C.
Object Type: Article
System: The UNT Digital Library
D = 5 Maximally Supersymmetric Yang-Mills Theory Diverges at Six Loops (open access)

D = 5 Maximally Supersymmetric Yang-Mills Theory Diverges at Six Loops

None
Date: October 31, 2012
Creator: Bern, Zvi; Carrasco, John Joseph; Dixon, Lance J.; Douglas, Michael R.; von Hippel, Matt & Johansson, Henrik
Object Type: Article
System: The UNT Digital Library
6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector (open access)

6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector

During NOVA operations it is planned to run the Fermilab Recycler in a 12 batch slip stacking mode. In preparation for this, measurements of the tune during a six batch injection and then as the beam is decelerated by changing the RF frequency have been carried out in the Main Injector. The coherent tune shifts due to the changing beam intensity were measured and compared well with the theoretically expected tune shift. The tune shifts due to changing RF frequency, required for slip stacking, also compare well with the linear theory, although some nonlinear affects are apparent at large frequency changes. These results give us confidence that the expected tunes shifts during 12 batch slip stacking Recycler operations can be accommodated.
Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Kourbanis, I.; Seiya, K. & Yan, M.-J.
Object Type: Article
System: The UNT Digital Library

7 L Ranch Quadrangle

Topographic map of a portion of Texas from the United States Geological Survey (USGS) project. The map includes towns, historic or notable sites, bodies of water, and other geologic features. Scale 1:24000
Date: 2012
Creator: Geological Survey (U.S.)
Object Type: Map
System: The Portal to Texas History
The "8(a) Program" for Small Businesses Owned and Controlled by the Socially and Economically Disadvantaged: Legal Requirements and Issues (open access)

The "8(a) Program" for Small Businesses Owned and Controlled by the Socially and Economically Disadvantaged: Legal Requirements and Issues

This report provides a brief history of the 8(a) Program, summarizes key requirements, and discusses legal challenges alleging that the program's presumption that members of certain racial and ethnic groups are socially disadvantaged violates the constitutional guarantee of equal protection.
Date: October 12, 2012
Creator: Manuel, Kate M. & Luckey, John R.
Object Type: Report
System: The UNT Digital Library
10 CFR 830 Major Modification Determination for Advanced Test Reactor LEU Fuel Conversion (open access)

10 CFR 830 Major Modification Determination for Advanced Test Reactor LEU Fuel Conversion

The Advanced Test Reactor (ATR), located in the ATR Complex of the Idaho National Laboratory (INL), was constructed in the 1960s for the purpose of irradiating reactor fuels and materials. Other irradiation services, such as radioisotope production, are also performed at ATR. The ATR is fueled with high-enriched uranium (HEU) matrix (UAlx) in an aluminum sandwich plate cladding. The National Nuclear Security Administration Global Threat Reduction Initiative (GTRI) strategic mission includes efforts to reduce and protect vulnerable nuclear and radiological material at civilian sites around the world. Converting research reactors from using HEU to low-enriched uranium (LEU) was originally started in 1978 as the Reduced Enrichment for Research and Test Reactors (RERTR) Program under the U.S. Department of Energy (DOE) Office of Science. Within this strategic mission, GTRI has three goals that provide a comprehensive approach to achieving this mission: The first goal, the driver for the modification that is the subject of this determination, is to convert research reactors from using HEU to LEU. Thus the mission of the ATR LEU Fuel Conversion Project is to convert the ATR and Advanced Test Reactor Critical facility (ATRC) (two of the six U.S. High-Performance Research Reactors [HPRR]) to LEU fuel by …
Date: May 1, 2012
Creator: Christensen, Boyd D.; Lehto, Michael A. & Duckwitz, Noel R.
Object Type: Report
System: The UNT Digital Library
10 CFR 830 Major Modification Determination for Advanced Test Reactor RDAS and LPCIS Replacement (open access)

10 CFR 830 Major Modification Determination for Advanced Test Reactor RDAS and LPCIS Replacement

The replacement of the ATR Control Complex's obsolete computer based Reactor Data Acquisition System (RDAS) and its safety-related Lobe Power Calculation and Indication System (LPCIS) software application is vitally important to ensure the ATR remains available to support this national mission. The RDAS supports safe operation of the reactor by providing 'real-time' plant status information (indications and alarms) for use by the reactor operators via the Console Display System (CDS). The RDAS is a computer support system that acquires analog and digital information from various reactor and reactor support systems. The RDAS information is used to display quadrant and lobe powers via a display interface more user friendly than that provided by the recorders and the Control Room upright panels. RDAS provides input to the Nuclear Engineering ATR Surveillance Data System (ASUDAS) for fuel burn-up analysis and the production of cycle data for experiment sponsors and the generation of the Core Safety Assurance Package (CSAP). RDAS also archives and provides for retrieval of historical plant data which may be used for event reconstruction, data analysis, training and safety analysis. The RDAS, LPCIS and ASUDAS need to be replaced with state-of-the-art technology in order to eliminate problems of aged computer systems, …
Date: May 1, 2012
Creator: Korns, David E.
Object Type: Report
System: The UNT Digital Library
10 CFR 850 Implementation of Requirements (open access)

10 CFR 850 Implementation of Requirements

10 CFR 850 defines a contractor as any entity, including affiliated entities, such as a parent corporation, under contract with DOE, including a subcontractor at any tier, with responsibility for performing work at a DOE site in furtherance of a DOE mission. The Chronic Beryllium Disease Prevention Program (CBDPP) applies to beryllium-related activities that are performed at the Lawrence Livermore National Laboratory (LLNL). The CBDPP or Beryllium Safety Program is integrated into the LLNL Worker Safety and Health Program and, thus, implementation documents and responsibilities are integrated in various documents and organizational structures. Program development and management of the CBDPP is delegated to the Environment, Safety and Health (ES&H) Directorate, Worker Safety and Health Functional Area. As per 10 CFR 850, Lawrence Livermore National Security, LLC (LLNS) periodically submits a CBDPP to the National Nuclear Security Administration/Livermore Site Office (NNSA/LSO). The requirements of this plan are communicated to LLNS workers through ES&H Manual Document 14.4, 'Working Safely with Beryllium.' 10 CFR 850 is implemented by the LLNL CBDPP, which integrates the safety and health standards required by the regulation, components of the LLNL Integrated Safety Management System (ISMS), and incorporates other components of the LLNL ES&H Program. As described in …
Date: January 5, 2012
Creator: Lee, S.
Object Type: Report
System: The UNT Digital Library
10-MW Supercritical-CO2 Turbine (Fact Sheet) (open access)

10-MW Supercritical-CO2 Turbine (Fact Sheet)

National Renewable Energy Laboratory is one of the 2012 SunShot CSP R&D awardees for their advanced power cycles. This fact sheet explains the motivation, description, and impact of the project.
Date: September 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The 12 GeV Energy Upgrade at Jefferson Laboratory (open access)

The 12 GeV Energy Upgrade at Jefferson Laboratory

Two new cryomodules and an extensive upgrade of the bending magnets at Jefferson Lab has been recently completed in preparation for the full energy upgrade in about one year. Jefferson Laboratory has undertaken a major upgrade of its flagship facility, the CW re-circulating CEBAF linac, with the goal of doubling the linac energy to 12 GeV. I will discuss here the main scope and timeline of the upgrade and report on recent accomplishments and the present status. I will then discuss in more detail the core of the upgrade, the new additional C100 cryomodules, their production, tests and recent successful performance. I will then conclude by looking at the future plans of Jefferson Laboratory, from the commissioning and operations of the 12 GeV CEBAF to the design of the MEIC electron ion collider.
Date: September 2012
Creator: Pilat, Fulvia C.
Object Type: Article
System: The UNT Digital Library
12 GeV Upgrade Project - Cryomodule Production (open access)

12 GeV Upgrade Project - Cryomodule Production

The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is producing ten 100+MV SRF cryomodules (C100) as part of the CEBAF 12 GeV Upgrade Project. Once installed, these cryomodules will become part of an integrated accelerator system upgrade that will result in doubling the energy of the CEBAF machine from 6 to 12 GeV. This paper will present a complete overview of the C100 cryomodule production process. The C100 cryomodule was designed to have the major components procured from private industry and assembled together at Jefferson Lab. In addition to measuring the integrated component performance, the performance of the individual components is verified prior to being released for production and assembly into a cryomodule. Following a comprehensive cold acceptance test of all subsystems, the completed C100 cryomodules are installed and commissioned in the CEBAF machine in preparation of accelerator operations. This overview of the cryomodule production process will include all principal performance measurements, acceptance criterion and up to date status of current activities.
Date: July 1, 2012
Creator: J. Hogan, A. Burrill, G.K. Davis, M.A. Drury, M. Wiseman
Object Type: Article
System: The UNT Digital Library
A 12 GHz RF Power Source for the CLIC Study (open access)

A 12 GHz RF Power Source for the CLIC Study

The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.
Date: July 3, 2012
Creator: Schirm, Karl; Curt, Stephane; Dobert, Steffen; McMonagle, Gerard; Rossat, Ghislain; Syratchev, Igor et al.
Object Type: Article
System: The UNT Digital Library
A 14 MeV Fusion Neutron Source for Material and Blanket Development and Fission Fuel Production (open access)

A 14 MeV Fusion Neutron Source for Material and Blanket Development and Fission Fuel Production

None
Date: July 30, 2012
Creator: Simonen, T. C.; Moir, R. W.; Molvik, A. W. & Ryutov, D. D.
Object Type: Article
System: The UNT Digital Library
20% Wind by 2030: Overcoming the Challenges in West Virginia (open access)

20% Wind by 2030: Overcoming the Challenges in West Virginia

Final Report for '20% Wind by 2030: Overcoming the Challenges in West Virginia'. The objective of this project was to examine the obstacles and constraints to the development of wind energy in West Virginia as well as the obstacles and constraints to the achievement of the national goal of 20% wind by 2030. For the portion contracted with WVU, there were four tasks in this examination of obstacles and constraints. Task 1 involved the establishment of a Wind Resource Council. Task 2 involved conducting limited research activities. These activities involved an ongoing review of wind energy documents including documents regarding the potential for wind farms being located on reclaimed surface mining sites as well as other brownfield sites. The Principal Investigator also examined the results of the Marshall University SODAR assessment of the potential for placing wind farms on reclaimed surface mining sites. Task 3 involved the conducting of outreach activities. These activities involved working with the members of the Wind Resource Council, the staff of the Regional Wind Energy Institute, and the staff of Penn Future. This task also involved the examination of the importance of transmission for wind energy development. The Principal Investigator kept informed as to transmission …
Date: February 15, 2012
Creator: Mann, Patrick & Risch, Christine
Object Type: Report
System: The UNT Digital Library
35 Years of Innovation: The National Renewable Energy Laboratory Leads the Way to a Clean Energy Future (Brochure) (open access)

35 Years of Innovation: The National Renewable Energy Laboratory Leads the Way to a Clean Energy Future (Brochure)

With a history of over 35 years of successful innovation, this booklet highlights some of the many successes throughout the years.
Date: February 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
50% Advanced Energy Design Guides: Preprint (open access)

50% Advanced Energy Design Guides: Preprint

This paper presents the process, methodology, and assumptions for the development of the 50% Energy Savings Advanced Energy Design Guides (AEDGs), a design guidance document that provides specific recommendations for achieving 50% energy savings above the requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004 in four building types: (1) Small to medium office buildings, (2) K-12 school buildings, (3) Medium to big box retail buildings, (4) Large hospital buildings.
Date: July 1, 2012
Creator: Bonnema, E.; Leach, M.; Pless, S.; Liu, B.; Wang, W.; Thornton, B. et al.
Object Type: Article
System: The UNT Digital Library

50 Years Later: Women, Work & the Work Ahead

Infographic commemorating the 50th anniversary of the American Women Report by outlining statistics and major events related to women's education and participation in the workforce from 1963 to 2012.
Date: 2012
Creator: United States. Women's Bureau.
Object Type: Poster
System: The UNT Digital Library
The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN (open access)

The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN

Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this timeframe, BAT detected (in the 15-55 keV band) 720 sources in an all-sky survey of which 428 are associated with AGN, most of which are nearby. Our sample has negligible incompleteness and statistics a factor of {approx}2 larger over similarly complete sets of AGN. Our sample contains (at least) 15 bona-fide Compton-thick AGN and 3 likely candidates. Compton-thick AGN represent a {approx}5% of AGN samples detected above 15 keV. We use the BAT dataset to refine the determination of the LogN-LogS of AGN which is extremely important, now that NuSTAR prepares for launch, towards assessing the AGN contribution to the cosmic X-ray background. We show that the LogN-LogS of AGN selected above 10 keV is now established to a {approx}10% precision. We derive the luminosity function of Compton-thick AGN and measure a space density of 7.9{sub -2.9}{sup +4.1} x 10{sup -5} Mpc{sup -3} for objects with a de-absorbed luminosity larger than 2 x 10{sup 42} erg s{sup -1}. …
Date: April 2, 2012
Creator: Ajello, M.; /KIPAC, Menlo Park; Alexander, D.M.; U., /Durham; Greiner, J.; /Garching, Max Planck Inst., MPE et al.
Object Type: Article
System: The UNT Digital Library