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A Study of Factorization and a Measurement of CP Violation (open access)

A Study of Factorization and a Measurement of CP Violation

We report on a study of the decay {bar B}{sup 0} {yields} D*{sup +} {omega}{pi}{sup -} with the BABAR detector at the PEP-II B-factory at the Stanford Linear Accelerator Center. Based on a sample of 232 million B{sup 0}{bar B}{sup 0} decays collected between 1999 and 2004, we measure the branching fraction {Beta}({bar B}{sup 0} {yields} D*{sup +} {omega}{pi}{sup -}) = (2.88 {+-} 0.21(stat.) {+-} 0.31(syst.)) x 10{sup -3}. We study the invariant mass spectrum of the {omega}{pi}{sup -} system in this decay. This spectrum is in good agreement with expectations based on factorization and the measured spectrum in {tau}{sup -} {yields} {omega}{pi}{sup -} {nu}{sub {tau}}. We also measure the polarization of the D*{sup +} as a function of the {omega}{pi}{sup -} mass. In the mass region 1.1 to 1.9 GeV we measure the fraction of longitudinal polarization of the D*{sup +} to be {Lambda}{sub L}/{Lambda} = 0.654 {+-} 0.042(stat.) {+-} 0.016(syst.). This is in agreement with the expectations from heavy-quark effective theory and factorization assuming that the decay proceeds as {bar B}{sup 0} {yields} D*{sup +} {rho}(1450){sup -}, {rho}(1450){sup -} {yields} {omega}{pi}{sup -}. Furthermore, we present the results on the time-dependent CP asymmetry in neutral B meson decays to …
Date: January 16, 2008
Creator: Dahmes, Bryan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
ARPES study of the evolution of band structure and charge density wave properties in RTe3 ( R=Y , La, Ce, Sm, Gd, Tb, and Dy) (open access)

ARPES study of the evolution of band structure and charge density wave properties in RTe3 ( R=Y , La, Ce, Sm, Gd, Tb, and Dy)

We present a detailed angle-resolved photoemission spectroscopy (ARPES) investigation of the RTe3 family, which sets this system as an ideal"textbook" example for the formation of a nesting driven charge density wave (CDW). This family indeed exhibits the full range of phenomena that can be associated to CDWinstabilities, from the opening of large gaps on the best nested parts of Fermi surface (up to 0.4 eV), to the existence of residual metallic pockets. ARPES is the best suited technique to characterize these features, thanks to its unique ability to resolve the electronic structure in k space. An additional advantage of RTe3 is that theband structure can be very accurately described by a simple two dimensional tight-binding (TB) model, which allows one to understand and easily reproduce many characteristics of the CDW. In this paper, we first establish the main features of the electronic structure by comparing our ARPES measurements with the linear muffin-tinorbital band calculations. We use this to define the validity and limits of the TB model. We then present a complete description of the CDW properties and of their strong evolution as a function of R. Using simple models, we are able to reproduce perfectly the evolution of gaps …
Date: January 16, 2008
Creator: Hussain, Zahid; Brouet, Veronique; Yang, Wanli; Zhou, Xingjiang; Hussain, Zahid; Moore, R. G. et al.
Object Type: Article
System: The UNT Digital Library
A Simultaneous Measurement of the Branching Fractions of Ten B to Double Charm Decays (open access)

A Simultaneous Measurement of the Branching Fractions of Ten B to Double Charm Decays

This dissertation presents a simultaneous measurement of the branching fractions of ten B {yields} D{sup (*)}{bar D}{sup (*)} decays. The measurements are derived from a sample of 2.32 x 10{sup 8} B{bar B} pairs collected by the BABAR detector at the PEP-II B Factory located at Stanford Linear Accelerator Center. The branching fractions (x 10{sup -4}) are: -0.10 {+-} 0.44 {+-} 0.15 (<0.59) for B{sup 0} {yields} D{sup 0}{bar D}{sup 0}; 1.01 {+-} 1.07 {+-} 0.35 (<2.92) for B{sup 0} {yields} D*{sup 0}{bar D}{sup 0}; -1.31 {+-} 1.05 {+-} 0.41 (<0.92) for B{sup 0} {yields} D*{sup 0}{bar D}*{sup 0}; 2.81 {+-} 0.43 {+-} 0.45 for B{sup 0} {yields} D{sup +}D{sup -}; 5.72 {+-} 0.64 {+-} 0.71 for B{sup 0} {yields} D*{sup +}D{sup -}; 8.11 {+-} 0.57 {+-} 0.97 for B{sup 0} {yields} D*{sup +}D*{sup -}; 3.76 {+-} 0.57 {+-} 0.45 for B{sup -} {yields} D{sup -}D{sup 0}; 3.56 {+-} 0.52 {+-} 0.39 for B{sup -} {yields} D*{sup -}D{sup 0}; 6.30 {+-} 1.32 {+-} 0.93 for B{sup -} {yields} D{sup -}D*{sup 0}; and 8.14 {+-} 1.17 {+-} 1.11 for B{sup -} {yields} D*{sup -}D*{sup 0}. The first uncertainty is statistical while the second is systematic. The number in parentheses is the …
Date: January 16, 2008
Creator: Lae, Chung Khim
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Propagation or failure of detonation across an air gap in an LX-17 column: continuous time-dependent detonation or shock speed using the Embedded Fiber Optic (EFO) technique (open access)

Propagation or failure of detonation across an air gap in an LX-17 column: continuous time-dependent detonation or shock speed using the Embedded Fiber Optic (EFO) technique

The detailed history of the shock/detonation wave propagation after crossing a room-temperature-room-pressure (RTP) air gap between a 25.4 mm diameter LX-17 donor column and a 25.4 mm diameter by 25.4 mm long LX-17 acceptor pellet is investigated for three different gap widths (3.07, 2.08, and 0.00 mm) using the Embedded Fiber Optic (EFO) technique. The 2.08 mm gap propagated and the 3.07 mm gap failed and this can be seen clearly and unambiguously in the EFO data even though the 25.4 mm-long acceptor pellet would be considered quite short for a determination by more traditional means such as pins.
Date: January 16, 2008
Creator: Hare, D E; Chandler, J B; Compton, S M; Garza, R G; Grimsley, D A; Hernandez, A et al.
Object Type: Report
System: The UNT Digital Library
Pitfalls of Transparency: Lessons Learned from the Milford Flats Fire (open access)

Pitfalls of Transparency: Lessons Learned from the Milford Flats Fire

The Community Environmental Monitoring Program (CEMP) consists of a network of 29 radiation and weather monitoring stations located over a 160,000-km2 area of southern Nevada, southwestern Utah, and southeastern California. The program provides stakeholders with a hands-on role in the monitoring for airborne radioactivity that could result from ongoing or past activities on the Nevada Test Site (NTS). The CEMP’s mission includes provisions for the transparency of the monitoring data as well as public accessibility to these data. This is accomplished through direct stakeholder participation, public outreach, and near real-time uploads of monitoring data to a publicly accessible web site located at http://cemp.dri.edu/. In early July 2007, a lightning strike ignited a wildfire just outside the city of Milford in southeastern Utah. This fire, named the Milford Flats Fire, grew rapidly and eventually became the largest wildfire in recorded history in the state, burning approximately 567 square miles. At about the same time, the pressurized ion chamber (PIC) located at the CEMP station in Milford began reporting average exposure rates that ranged from four to seven times normal for the area. Initially, it was believed that elevated readings could be a result of gamma-emitting radon progeny released by the fire …
Date: January 16, 2008
Creator: Hartwell, T.; Shafer, D.; Tappen, J.; McCurdy, G.; Hurley, B. & Farmer, D.
Object Type: Article
System: The UNT Digital Library
Inverse-Transition Radiation Laser Acceleration Experiments at SLAC (open access)

Inverse-Transition Radiation Laser Acceleration Experiments at SLAC

We present a series of laser-driven particle acceleration experiments that are aimed at studying laser-particle acceleration as an inverse-radiation process. To this end we employ a semi-open vacuum setup with a thin planar boundary that interacts with the laser and the electromagnetic field of the electron beam. Particle acceleration from different types of boundaries will be studied and compared to the theoretical expectations from the Inverse-radiation picture and the field path integral method. We plan to measure the particle acceleration effect from transparent, reflective, black, and rough surface boundaries. While the agreement between the two acceleration pictures is straightforward to prove analytically for the transparent and reflective boundaries the equivalence is not clear-cut for the absorbing and rough-surface boundaries. Experimental observation may provide the evidence to distinguish between the models.
Date: January 16, 2008
Creator: Colby, Eric R.; Ischebeck, R.; Mcguinness, C.; Noble, R. J.; Sears, CMS; Siemann, Robert H. et al.
Object Type: Article
System: The UNT Digital Library
Binary Pseudo-random Grating Standard for Calibration of Surface Profilometers (open access)

Binary Pseudo-random Grating Standard for Calibration of Surface Profilometers

We suggest and describe the use of a binary pseudo-random (BPR) grating as a standard test surface for measurement of the modulation transfer function (MTF) of interferometric microscopes. Knowledge of the MTF of a microscope is absolutely necessary to convert the measured height distribution of a surface undergoing metrology into an accurate power spectral density (PSD) distribution. For an'ideal' microscope with an MTF function independent of spatial frequency out to the Nyquist frequency of the detector array with zero response at higher spatial frequencies, a BPR grating would produce a flat 1D PSD spectrum, independent of spatial frequency. For a'real' instrument, the MTF is found as the square root of the ratio of the PSD spectrum measured with the BPR grating to the'ideal,' spatial frequency independent, PSD spectrum. We present the results from a measurement of the MTF of MicromapTM-570 interferometric microscope demonstrating a high efficiency for the calibration method.
Date: January 16, 2008
Creator: Yashchuk, Valeriy; Yashchuk, Valeriy V.; McKinney, Wayne R. & Takacs, Peter Z.
Object Type: Article
System: The UNT Digital Library
Seismic Data for Evaluation of Ground Motion Hazards in Las Vegas in Support of Test Site Readiness Ground Motion (open access)

Seismic Data for Evaluation of Ground Motion Hazards in Las Vegas in Support of Test Site Readiness Ground Motion

In this report we describe the data sets used to evaluate ground motion hazards in Las Vegas from nuclear tests at the Nevada Test Site. This analysis is presented in Rodgers et al. (2005, 2006) and includes 13 nuclear explosions recorded at the John Blume and Associates network, the Little Skull Mountain earthquake and a temporary deployment of broadband station in Las Vegas. The data are available in SAC format on CD-ROM as an appendix to this report.
Date: January 16, 2008
Creator: Rodgers, A
Object Type: Report
System: The UNT Digital Library
Search for Rare Quark-Annihilation Decays, Charged B Mesons Decaying to Charged D(S) Mesons And Phi Mesons (open access)

Search for Rare Quark-Annihilation Decays, Charged B Mesons Decaying to Charged D(S) Mesons And Phi Mesons

The authors report on a search for the decay B{sup {+-}} {yields} D{sub s}{sup (*){+-}} {phi} using 212.2 fb{sup -1} of data collected with the BABAR detector at the PEP-II B Factory at the Stanford Linear Accelerator Center between 1999 and 2004. This sample of 234 x 10{sup 6} e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} events yields no significant signal. They report the Bayesian upper limits {Beta}(B{sup {+-}} {yields} D{sub s}{sup {+-}} {phi}) x {Beta}(D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}) < 8.6 x 10{sup -8} and {Beta}(B{sup {+-}} {yields} D*{sub s}{sup {+-}}{phi}) x {Beta}(D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}) < 5.4 x 10{sup -7} at the 90% C.L. Using the latest measurement of {Beta}(D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}), they report: {Beta}(B{sup {+-}} {yields} D{sub s}{sup {+-}}{phi}) < 1.8 x 10{sup -6} and {Beta}(B{sup {+-}} {yields} D*{sub s}{sup {+-}}{phi}) < 1.1 x 10{sup -5} at the 90% C.L.
Date: January 16, 2008
Creator: Cunha, J.Adam M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Net Weight Issue LLNL DOE-STD-3013 Containers (open access)

Net Weight Issue LLNL DOE-STD-3013 Containers

The following position paper will describe DOE-STD-3013 container sets No.L000072 and No.L000076, and how they are compliant with DOE-STD-3013-2004. All masses of accountable nuclear materials are measured on LLNL certified balances maintained under an MC&A Program approved by DOE/NNSA LSO. All accountability balances are recalibrated annually and checked to be within calibration on each day that the balance is used for accountability purposes. A statistical analysis of the historical calibration checks from the last seven years indicates that the full-range Limit of Error (LoE, 95% confidence level) for the balance used to measure the mass of the contents of the above indicated 3013 containers is 0.185 g. If this error envelope, at the 95% confidence level, were to be used to generate an upper-limit to the measured weight of the containers No.L000072 and No.L000076, the error-envelope would extend beyond the 5.0 kg 3013-standard limit on the package contents by less than 0.3 g. However, this is still well within the intended safety bounds of DOE-STD-3013-2004.
Date: January 16, 2008
Creator: Wilk, P
Object Type: Report
System: The UNT Digital Library
The Beta-Neutrino Correlation in Sodium-21 and Other Nuclei (open access)

The Beta-Neutrino Correlation in Sodium-21 and Other Nuclei

We have measured the mbox beta - nu correlation coefficient,a_beta nu, in 21Na using a laser-trapped sample. We measure the energyspectrum of the recoil nuclei by measuring their time-of-flight incoincidence with the atomic electrons shaken off in beta decay. Highdetectionefficiency of these low-energy electrons allows good countingstatistics, even with low trap density, which suppresses thephotoassociation of molecular sodium, which can cause a large systematicerror. Our measurement, with a 1 percent fractional uncertainty, agreeswith the Standard Model prediction but disagrees with our previousmeasurement which was susceptible to error introduced by molecularsodium. We summarize precise measurements of a_ beta nu and theirconsequences for searches for Beyond Standard Model scalar and tensorcurrent couplings.
Date: January 16, 2008
Creator: Vetter, Paul A.; Abo-Shaeer, Jamil; Freedman, Stuart J. & Maruyama, Reina
Object Type: Article
System: The UNT Digital Library
CH-TRU Waste Content Codes (open access)

CH-TRU Waste Content Codes

The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container. Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 …
Date: January 16, 2008
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library
Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation (open access)

Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation

Aneurysm re-growth and rupture can sometimes unexpectedly occur following treatment procedures that were initially considered to be successful at the time of treatment and post-operative angiography. In some cases, this can be attributed to surgical clip slippage or endovascular coil compaction. However, there are other cases in which the treatment devices function properly. In these instances, the subsequent complications are due to other factors, perhaps one of which is the post-treatment hemodynamic stress. To investigate whether or not a treatment procedure can subject the parent artery to harmful hemodynamic stresses, computational fluid dynamics simulations are performed on a patient-specific basilar aneurysm and bifurcation before and after a virtual endovascular treatment. The simulations demonstrate that the treatment procedure produces a substantial increase in the wall shear stress. Analysis of the post-treatment flow field indicates that the increase in wall shear stress is due to the impingement of the basilar artery flow upon the aneurysm filling material and to the close proximity of a vortex tube to the artery wall. Calculation of the time-averaged wall shear stress shows that there is a region of the artery exposed to a level of wall shear stress that can cause severe damage to endothelial cells. …
Date: January 16, 2008
Creator: Ortega, J; Hartman, J; Rodriguez, J & Maitland, D
Object Type: Article
System: The UNT Digital Library
A Search for B+ to K+ Nu Anti-Nu (open access)

A Search for B+ to K+ Nu Anti-Nu

A search for the rare, flavour-changing neutral current decay B{sup +} {yields} K{sup +} {nu}{bar {nu}} is presented using 81.9 fb{sup -1} of data collected at the {Upsilon}(4S) resonance by the BABAR experiment. Signal candidate events are selected through the identification of a high momentum charged kaon and significant missing energy, where the companion B{sup -} in the event has decayed semileptonically via B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}} X and X is kinematically constrained to be either nothing or a low momentum transition photon or {pi}{sup 0}. The analysis was performed blind and 6 candidates were selected with a background expectation of 3.4 {+-} 1.2. This leads to a limit on the branching fraction of {Beta} (B{sup +} {yields} K{sup +} {nu}{bar {nu}}) < 7.2 x 10{sup -5} at 90% confidence level. We also search for the reaction B{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} and extract a limit on the branching fraction of {Beta}(B{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}) < 2.5 x 10{sup -4} at 90% confidence level.
Date: January 16, 2008
Creator: Jackson, Paul D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
UITI2007-University Information Technical Interchange Review Meeting (open access)

UITI2007-University Information Technical Interchange Review Meeting

None
Date: January 16, 2008
Creator: Franques, V.; Williams, R.; Schubert, S.; Bloch, J.; Ostrogorsky, A.; Burger, A. et al.
Object Type: Article
System: The UNT Digital Library
CHEMICAL SLUDGE HEEL REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT 8183 (open access)

CHEMICAL SLUDGE HEEL REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT 8183

Chemical Sludge Removal (CSR) is the final waste removal activity planned for some of the oldest nuclear waste tanks located at the Savannah River Site (SRS) in Aiken, SC. In 2008, CSR will be used to empty two of these waste tanks in preparation for final closure. The two waste tanks chosen to undergo this process have previously leaked small amounts of nuclear waste from the primary tank into an underground secondary containment pan. CSR involves adding aqueous oxalic acid to the waste tank in order to dissolve the remaining sludge heel. The resultant acidic waste solution is then pumped to another waste tank where it will be neutralized and then stored awaiting further processing. The waste tanks to be cleaned have a storage capacity of 2.84E+06 liters (750,000 gallons) and a target sludge heel volume of 1.89E+04 liters (5,000 gallons) or less for the initiation of CSR. The purpose of this paper is to describe the CSR process and to discuss the most significant technical issues associated with the development of CSR.
Date: January 16, 2008
Creator: Thaxton, D & Timothy Baughman, T
Object Type: Article
System: The UNT Digital Library
Performance of a MEMS-base Adaptive Optics Optical Coherency Tomography System (open access)

Performance of a MEMS-base Adaptive Optics Optical Coherency Tomography System

We have demonstrated that a microelectrical mechanical systems (MEMS) deformable mirror can be flattened to < 1 nm RMS within controllable spatial frequencies over a 9.2-mm aperture making it a viable option for high-contrast adaptive optics systems (also known as Extreme Adaptive Optics). The Extreme Adaptive Optics Testbed at UC Santa Cruz is being used to investigate and develop technologies for high-contrast imaging, especially wavefront control. A phase shifting diffraction interferometer (PSDI) measures wavefront errors with sub-nm precision and accuracy for metrology and wavefront control. Consistent flattening, required testing and characterization of the individual actuator response, including the effects of dead and low-response actuators. Stability and repeatability of the MEMS devices was also tested. An error budget for MEMS closed loop performance will summarize MEMS characterization.
Date: January 16, 2008
Creator: Evans, J.; Zadwadzki, R. J.; Jones, S.; Olivier, S.; Opkpodu, S. & Werner, J. S.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 38, No. 594, Ed. 1 Wednesday, January 16, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 594, Ed. 1 Wednesday, January 16, 2008

Free weekly newspaper that includes business and classified advertising.
Date: January 16, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Earthquakes: Risk, Monitoring, Notification, and Research (open access)

Earthquakes: Risk, Monitoring, Notification, and Research

This report describes estimates of earthquake hazards and risk in the United States; the current federal programs that support earthquake monitoring and that provide notification after a seismic event; and the programs that support mitigation and research aimed at reducing U.S. vulnerability to earthquakes.
Date: January 16, 2008
Creator: Folger, Peter
Object Type: Report
System: The UNT Digital Library
Cherokeean Herald (Rusk, Tex.), Vol. 158, No. 47, Ed. 1 Wednesday, January 16, 2008 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 158, No. 47, Ed. 1 Wednesday, January 16, 2008

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: January 16, 2008
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 2, Ed. 1 Wednesday, January 16, 2008 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 2, Ed. 1 Wednesday, January 16, 2008

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: January 16, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Department of Housing and Urban Development: FY2008 Appropriations (open access)

The Department of Housing and Urban Development: FY2008 Appropriations

This report tracks the FY2008 congressional appropriations process and provides a detailed discussion of the funding and issues related to the majority of accounts in HUD’s budget.
Date: January 16, 2008
Creator: McCarty, Maggie; Perl, Libby; Foote, Bruce E.; Boyd, Eugene & Peterson, Meredith
Object Type: Report
System: The UNT Digital Library
William Wilberforce Trafficking Victims Protection Reauthorization Act of 2007 (H.R. 3887 as Passed by the House: Criminal Provisions in Short (open access)

William Wilberforce Trafficking Victims Protection Reauthorization Act of 2007 (H.R. 3887 as Passed by the House: Criminal Provisions in Short

None
Date: January 16, 2008
Creator: Doyle, Charles
Object Type: Report
System: The UNT Digital Library
The Greensheet (Dallas, Tex.), Vol. 31, No. 281, Ed. 1 Wednesday, January 16, 2008 (open access)

The Greensheet (Dallas, Tex.), Vol. 31, No. 281, Ed. 1 Wednesday, January 16, 2008

Free weekly newspaper that includes business and classified advertising.
Date: January 16, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History