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 Decade: 2010-2019
$D^0 \bar{D}^0$ Mixing at BaBar

$D^0 \bar{D}^0$ Mixing at BaBar

Date: October 26, 2011
Creator: Coleman, Jonathon & /SLAC
Description: This article reviews the recent measurement of D{sup 0}-{bar D}{sup 0} mixing with the D{sup 0} {yields} K{pi} decay channel from the BABAR experiment at the PEP-II B-Factory. Averages from the Heavy Flavor Averaging Group between this result and a previous result from BELLE are also presented.
Contributing Partner: UNT Libraries Government Documents Department
1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet

1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet

Date: April 1, 2013
Creator: Shinn, Michelle D. & Benson, Stephen V.
Description: The UVFEL at Jefferson Lab has provided a 10 eV photon beam for users by outcoupling the coherent third harmonic of the UVFEL operated at 372 nm. This can provide up to tens of milliwatts of power in the VUV. Operation of the FEL at the fundamental might enhance this power by up to a factor of 1000. With minor upgrades to the accelerator now underway and a new undulator proposed by Calabazas Creek Research, Inc. we show that we can lase in the fundamental at 124 nm. The predicted output is higher by four orders of magnitude on an average power basis and six orders of magnitude on a peak fluence basis than the Advanced Light Source at Lawrence Berkeley National Laboratory.
Contributing Partner: UNT Libraries Government Documents Department
1.3 GHz superconducting RF cavity program at Fermilab

1.3 GHz superconducting RF cavity program at Fermilab

Date: March 1, 2011
Creator: Ginsburg, C.M.; Arkan, T.; Barbanotti, S.; Carter, H.; Champion, M.; Cooley, L. et al.
Description: At Fermilab, 9-cell 1.3 GHz superconducting RF (SRF) cavities are prepared, qualified, and assembled into cryomodules (CMs) for Project X, an International Linear Collider (ILC), or other future projects. The 1.3 GHz SRF cavity program includes targeted R&D on 1-cell 1.3 GHz cavities for cavity performance improvement. Production cavity qualification includes cavity inspection, surface processing, clean assembly, and one or more cryogenic low-power CW qualification tests which typically include performance diagnostics. Qualified cavities are welded into helium vessels and are cryogenically tested with pulsed high-power. Well performing cavities are assembled into cryomodules for pulsed high-power testing in a cryomodule test facility, and possible installation into a beamline. The overall goals of the 1.3 GHz SRF cavity program, supporting facilities, and accomplishments are described.
Contributing Partner: UNT Libraries Government Documents Department
1.5D Quasilinear Model for Alpha Particle-TAE Interaction in ARIES ACT-I

1.5D Quasilinear Model for Alpha Particle-TAE Interaction in ARIES ACT-I

Date: January 30, 2013
Creator: Ghantous, K.; Gorelenkov, N. N.; Kessel, C. & Poli, F.
Description: We study the TAE interaction with alpha particle fusion products in ARIES ACT-I using the 1.5D quasilinear model. 1.5D uses linear analytic expressions for growth and damping rates of TAE modes evaluated using TRANSP pro les to calculates the relaxation of pressure pro les. NOVA- K simulations are conducted to validate the analytic dependancies of the rates, and to normalize their absolute value. The low dimensionality of the model permits calculating loss diagrams in large parameter spaces.
Contributing Partner: UNT Libraries Government Documents Department
1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

Date: March 19, 2010
Creator: Zylstra, A; Barnard, J J & More, R M
Description: One dimensional simulations of various initial average density aluminum foams (modeled as slabs of solid metal separated by low density regions) heated by volumetric energy deposition are conducted with a Lagrangian hydrodynamics code using a van der Waals equation of state (EOS). The resulting behavior is studied to facilitate the design of future warm dense matter (WDM) experiments at LBNL. In the simulations the energy deposition ranges from 10 to 30 kJ/g and from 0.075 to 4.0 ns total pulse length, resulting in temperatures from approximately 1 to 4 eV. We study peak pressures and temperatures in the foams, expansion velocity, and the phase evolution. Five relevant time scales in the problem are identified. Additionally, we present a method for characterizing the level of inhomogeneity in a foam target as it is heated and the time it takes for a foam to homogenize.
Contributing Partner: UNT Libraries Government Documents Department
1 GeV CW nonscaling FFAG for ADS, and magnet parameters

1 GeV CW nonscaling FFAG for ADS, and magnet parameters

Date: May 20, 2012
Creator: Johnstone, C.; Meot, F.; Snopok, P. & Weng, W.
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
1 mil gold bond wire study.

1 mil gold bond wire study.

Date: May 1, 2013
Creator: Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W. & Rutherford, Brian Milne
Description: In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.
Contributing Partner: UNT Libraries Government Documents Department
2 x 2 Polyethylene Reflected and Moderated Highly Enriched Uranium System with Rhenium

2 x 2 Polyethylene Reflected and Moderated Highly Enriched Uranium System with Rhenium

Date: September 1, 2010
Creator: Ellis, A. Nichole; Hutchinson, Jesson; Bess, John D.; Polyakov, Dmitry N.; Glushkov, Evgeny S. & Glushkov, Alexey E.
Description: The 2 × 2 array HEU-Re experiment was performed on the Planet universal critical assembly machine on November 4th, 2003 at the Los Alamos Critical Experiments Facility (LACEF) at Los Alamos National Laboratory (LANL). For this experiment, there were 10 ½ units, each full unit containing four HEU foils and two rhenium foils. The top unit contained only two HEU foils and two rhenium foils. A total of 42 HEU foils were used for this experiment. Rhenium is a desirable cladding material for space nuclear power applications. This experiment consisted of HEU foils interleaved with rhenium foils and is moderated and reflected by polyethylene plates. A unit consisted of a polyethylene plate, which has a recess for rhenium foils, and four HEU foils in a single layer in the top recess of each polyethylene plate. The Planet universal criticality assembly machine has been previously used in experiments containing HEU foils interspersed with SiO2 (HEU-MET-THERM-001), Al (HEU-MET-THERM-008), MgO (HEU-MET-THERM-009), Gd foils (HEU-MET-THERM-010), 2 × 2 × 26 Al (HEU-MET-THERM-012), Fe (HEU-MET-THERM-013 and HEU-MET-THERM-015), 2 × 2 × 23 SiO2 (HEU-MET-THERM-014), 2 × 2 × 11 hastalloy plates (HEU-MET-THERM-016), and concrete (HEU-MET-THERM-018). The 2 × 2 array of HEU-Re is considered acceptable ...
Contributing Partner: UNT Libraries Government Documents Department
3,4,3-LI(1,2-HOPO): In Vitro Formation of Highly Stable Lanthanide Complexes Translates into Efficacious In Vivo Europium Decorporation

3,4,3-LI(1,2-HOPO): In Vitro Formation of Highly Stable Lanthanide Complexes Translates into Efficacious In Vivo Europium Decorporation

Date: July 13, 2011
Creator: Sturzbecher-Hoehne, Manuel; Ng Pak Leung, Clara; Daleo, Anthony; Kullgren, Birgitta; Prigent, Anne-Laure; Shuh, David K. et al.
Description: The spermine-based hydroxypyridonate octadentate chelator 3,4,3-LI(1,2-HOPO) was investigated for its ability to act as an antennae that sensitizes the emission of Sm{sup III}, Eu{sup III}, and Tb{sup III} in the Visible range (Φ{sub tot} = 0.2 - 7%) and the emission of Pr{sup III}, Nd{sup III}, Sm{sup III}, and Yb{sup III} in the Near Infra-Red range, with decay times varying from 1.78 μs to 805 μs at room temperature. The particular luminescence spectroscopic properties of these lanthanide complexes formed with 3,4,3-LI(1,2-HOPO) were used to characterize their respective solution thermodynamic stabilities as well as those of the corresponding La{sup III}, Gd{sup III}, Dy{sup III}, Ho{sup III}, Er{sup III}, Tm{sup III}, and Lu{sup III} complexes. The remarkably high affinity of 3,4,3-LI(1,2-HOPO) for lanthanide metal ions and the resulting high complex stabilities (pM values ranging from 17.2 for La{sup III} to 23.1 for Yb{sup III}) constitute a necessary but not sufficient criteria to consider this octadentate ligand an optimal candidate for in vivo metal decorporation. The in vivo lanthanide complex stability and decorporation capacity of the ligand were assessed, using the radioactive isotope {sup 152}Eu as a tracer in a rodent model, which provided a direct comparison with the in vitro thermodynamic results ...
Contributing Partner: UNT Libraries Government Documents Department
The 3.8% Medicare Contribution Tax on Unearned Income, Including Real Estate Transactions

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

Date: May 18, 2012
Creator: unknown
Description: None
Contributing Partner: UNT Libraries Government Documents Department
A 3% Measurement of the Beam Normal Single Spin Asymmetry in Forward Angle Elastic Electron-Proton Scattering using the Qweak Setup

A 3% Measurement of the Beam Normal Single Spin Asymmetry in Forward Angle Elastic Electron-Proton Scattering using the Qweak Setup

Date: August 1, 2013
Creator: Waidyawansa, Dinayadura Buddhini
Description: The beam normal single spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable of the imaginary part of the two-photon exchange process. Moreover, it is a potential source of false asymmetry in parity violating electron scattering experiments. The Q{sub weak} experiment uses parity violating electron scattering to make a direct measurement of the weak charge of the proton. The targeted 4% measurement of the weak charge of the proton probes for parity violating new physics beyond the Standard Model. The beam normal single spin asymmetry at Q{sub weak} kinematics is at least three orders of magnitude larger than 5 ppb precision of the parity violating asymmetry. To better understand this parity conserving background, the Q{sub weak} Collaboration has performed elastic scattering measurements with fully transversely polarized electron beam on the proton and aluminum. This dissertation presents the analysis of the 3% measurement (1.3% statistical and 2.6% systematic) of beam normal single spin asymmetry in electronproton scattering at a Q2 of 0.025 (GeV/c)2. It is the most precise existing measurement of beam normal single spin asymmetry available at the time. A measurement of this precision helps to improve the theoretical models on beam normal ...
Contributing Partner: UNT Libraries Government Documents Department
A 3 TeV Muon Collider Lattice Design

A 3 TeV Muon Collider Lattice Design

Date: May 1, 2012
Creator: Alexahin, Y.; Gianfelice-Wendt, E. & /Fermilab
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
A 4.2 GS/S Synchronized Vertical Excitation System for SPS Studies - Steps Toward Wideband Feedback

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

Date: October 18, 2013
Creator: Fox, J.D.; Olsen, J.; Rivetta, C.; Rivetta, I.; Turgut, O.; Uemura, S. et al.
Description: Abstract Not Provided
Contributing Partner: UNT Libraries Government Documents Department
A 4.2 GS/sec. Synchronized Vertical Excitation System for SPS Studies - Steps Toward Wideband Feedback

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

Date: July 10, 2012
Creator: Fox, John
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
4 kW Test of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells

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

Date: June 1, 2012
Creator: O'Brien, J. E.; Zhang, X.; Housley, G. K.; Moore-McAteer, L. & Tao, G.
Description: 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. ...
Contributing Partner: UNT Libraries Government Documents Department
N >= 4 Supergravity Amplitudes from Gauge Theory at One Loop

N >= 4 Supergravity Amplitudes from Gauge Theory at One Loop

Date: August 19, 2011
Creator: Bern, Z.; /UCLA; Boucher-Veronneau, C.; /SLAC; Johansson, H. & /Saclay
Description: We expose simple and practical relations between the integrated four- and five-point one-loop amplitudes of N {ge} 4 supergravity and the corresponding (super-)Yang-Mills amplitudes. The link between the amplitudes is simply understood using the recently uncovered duality between color and kinematics that leads to a double-copy structure for gravity. These examples provide additional direct confirmations of the duality and double-copy properties at loop level for a sample of different theories.
Contributing Partner: UNT Libraries Government Documents Department
N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops

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

Date: February 15, 2012
Creator: Boucher-Veronneau, C.; Dixon, L.J. & /SLAC
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
A 4 to 0.1 nm FEL Based on the SLAC Linac

A 4 to 0.1 nm FEL Based on the SLAC Linac

Date: June 5, 2012
Creator: Pellegrini, C. & /UCLA
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
D = 5 Maximally Supersymmetric Yang-Mills Theory Diverges at Six Loops

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

Date: October 31, 2012
Creator: Bern, Zvi; Carrasco, John Joseph; Dixon, Lance J.; Douglas, Michael R.; von Hippel, Matt & Johansson, Henrik
Description: Abstract Not Provided
Contributing Partner: UNT Libraries Government Documents Department
6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector

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

Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Kourbanis, I.; Seiya, K. & Yan, M.-J.
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
The "8(a) Program" for Small Businesses Owned and Controlled by the Socially and Economically Disadvantaged: Legal Requirements and Issues

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

Date: October 12, 2012
Creator: Manuel, Kate M. & Luckey, John R.
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
The “8(a) Program” for Small Businesses Owned and Controlled by the Socially and Economically Disadvantaged: Legal Requirements and Issues

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

Date: November 26, 2014
Creator: unknown
Description: None
Contributing Partner: UNT Libraries Government Documents Department
The “8(a) Program” for Small Businesses Owned and Controlled by the Socially and Economically Disadvantaged: Legal Requirements and Issues

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

Date: March 18, 2010
Creator: unknown
Description: None
Contributing Partner: UNT Libraries Government Documents Department
8(a) Program: Fourteen Ineligible Firms Received $325 Million in Sole-Source and Set-Aside Contracts

8(a) Program: Fourteen Ineligible Firms Received $325 Million in Sole-Source and Set-Aside Contracts

Date: March 30, 2010
Creator: United States. Government Accountability Office.
Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Small Business Administration (SBA) helps socially and economically disadvantaged small businesses gain access to federal contracting opportunities through its 8(a) program. To participate, firms must be at least 51 percent owned and controlled by an individual who meets SBA's criteria of socially and economically disadvantaged. The firm must also qualify as a small business. Once certified, 8(a) firms are eligible to receive sole-source and set-aside contracts for up to 9 years. GAO was asked to (1) determine whether ineligible firms are participating in the 8(a) program, (2) proactively test SBA's controls over the 8(a) application process, and (3) determine what vulnerabilities, if any, exist in SBA's fraud prevention system. To identify cases, GAO reviewed SBA data and complaints to GAO's fraud hotline. To perform its proactive testing, GAO created four bogus businesses and applied for 8(a) certification. GAO did not attempt to project the extent of fraud and abuse in the program."
Contributing Partner: UNT Libraries Government Documents Department
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