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The Quirky Collider Signals of Folded Supersymmetry (open access)

The Quirky Collider Signals of Folded Supersymmetry

We investigate the collider signals associated with scalar quirks ('squirks') in folded supersymmetric models. As opposed to regular superpartners in supersymmetric models these particles are uncolored, but are instead charged under a new confining group, leading to radically different collider signals. Due to the new strong dynamics, squirks that are pair produced do not hadronize separately, but rather form a highly excited bound state. The excited 'squirkonium' loses energy to radiation before annihilating back into Standard Model particles. We calculate the branching fractions into various channels for this process, which is prompt on collider time-scales. The most promising annihilation channel for discovery is W+photon which dominates for squirkonium near its ground state. We demonstrate the feasibility of the LHC search, showing that the mass peak is visible above the SM continuum background and estimate the discovery reach.
Date: August 1, 2008
Creator: Burdman, Gustavo; Chacko, Z.; Goh, Hock-Seng; Harnik, Roni & Krenke, Christopher A.
Object Type: Article
System: The UNT Digital Library
14-MeV Neutron Generator Used as a Thermal Neutron Source (open access)

14-MeV Neutron Generator Used as a Thermal Neutron Source

One of the most important applications of the general purpose Monte Carlo N-Particle (MCNPS and MCNPX) codes is neutron shielding design. We employed this method to simulate the shield of a 14-MeV neutron generator used as a thermal neutron source providing an external thermal neutron beam for testing large area neutron detectors developed for diffraction studies in biology and also useful for national security applications. Nuclear reactors have been the main sources of neutrons used for scientific applications. In the past decade, however, a large number of reactors have been shut down, and the importance of other, smaller devices capable of providing neutrons for research has increased. At Brookhaven National Laboratory a moderated Am-Be neutron source with shielding is used for neutron detector testing. This source is relatively weak, but provides a constant flux of neutrons, even when not in use. The use of a 14 MeV energized neutron generator, with an order of magnitude higher neutron flux has been considered to replace the Am-Be source, but the higher fast neutron yield requires a more careful design of moderator and shielding. In the present paper we describe a proposed shielding configuration based on Monte Carlo calculations, and provide calculated neutron …
Date: August 10, 2008
Creator: Dioszegi, I.
Object Type: Article
System: The UNT Digital Library
Comparison of meteorological measurements from sparse and dense surface observational networks in the U.S. southern Great Plains. (open access)

Comparison of meteorological measurements from sparse and dense surface observational networks in the U.S. southern Great Plains.

The primary objective of this study was to analyze the spatial variability of temperature and relative humidity across Kansas (KS) and Oklahoma (OK) for sparse and dense networks by comparing data from (1) the Surface Meteorological Observing System (SMOS) installations at the Atmospheric Radiation Measurement (ARM; Peppler et al. 2007) Program's Southern Great Plains site and (2) the Oklahoma Mesonet (OKM; McPherson et al. 2007). Given the wealth of observations available from these networks, this study provided the unique opportunity to determine, within a quantifiable statistical limit, an optimal distance between stations deployed for observation of the climatological values of temperature and relative humidity. Average distances between a given station and its closest neighboring station for the ARM SMOS ({approx} 70 km) and the OKM ({approx} 30 km; Brotzge and Richardson 2003) networks provided an excellent framework for comparisons of sparse and dense observations (Figure 1). This study further lays groundwork for a future investigation to determine the necessary spacing between observations for initialization of gridded numerical models. The spatial variability of temperature and relative humidity was examined over KS and OK by comparing observations between station pairs located in three primary domains: (1) a sparse domain in KS, consisting …
Date: August 13, 2008
Creator: Monroe, J. W.; Ritsche, M. T.; Franklin, M.; Kehoe, K. E.; Division, Environmental Science & Oklahoma, Univ.of
Object Type: Report
System: The UNT Digital Library

Application of Proteomics and Lipid Studies in Environmental Biotechnology

The overview of changes in protein levels or states in response to a growth condition, stress, mutation or metabolic engineering is invaluable in understanding the physiology of a microbial system. The lipid profile of the cell is similarly a valuable diagnostic of the cellular response and health, especially in context of survival in a fluctuating environment. To obtain comprehensive cellular models, post-transcriptional cell wide surveys at the levels of proteins and lipids are required. Both these fields have been greatly bolstered by the development of high throughput methods using mass spectrometry. Multiple strategies now exist for the identification of proteins, and numerous workflows to quantify protein abundance have also been developed. Cellular profiling such as these allows us to assess the potential of a microbial system for environmental applications such as bioremediation and bio-energy.
Date: August 12, 2008
Creator: Mukhopadhyay, Aindrila
Object Type: Presentation
System: The UNT Digital Library
GLASS FORMULATION DEVELOPMENT AND TESTING FOR COLD CRUCIBLE INDUCTION MELTER (CCIM) ADVANCED REMEDIATION TECHNOLOGIES DEMONSTRATION PROJECT - 9208 (open access)

GLASS FORMULATION DEVELOPMENT AND TESTING FOR COLD CRUCIBLE INDUCTION MELTER (CCIM) ADVANCED REMEDIATION TECHNOLOGIES DEMONSTRATION PROJECT - 9208

Over the past few years, Cold Crucible Induction Melter (CCIM) demonstrations have been completed using SRS sludge batches 2, 3 and 4 (SB2, SB3 and SB4) simulant compositions. These campaigns demonstrated the ability of the CCIM to effectively produce quality glasses at high waste loadings. The current Advanced Remediation Technology (ART) Phase II-A Project is aimed at demonstrating the CCIM technology under representative DWPF flowsheet conditions and to demonstrate extended operations of the melter. A glass composition development effort was completed to identify and recommend a frit composition and sludge batch 4 (SB4) simulant waste loading target for subsequent ART-Phase II-A CCIM demonstration testing. Based on the results of the glass formulation testing, it was recommended that the Frit 503-R6 composition (B{sub 2}O{sub 3} = 14 wt %; Li{sub 2}O = 9 wt %; Na{sub 2}O = 3 wt %; and SiO{sub 2} = 74 wt %) be utilized for the demonstration. Furthermore, a waste loading of 46 wt % was recommended. The recommended frit and waste loading would produce a glass with acceptable durability with a liquidus temperature adequately below the 1250 C nominal CCIM operating temperature. This frit composition and waste loading was found to result in a …
Date: August 27, 2008
Creator: Marra, J; Amanda Billings, A; David Peeler, D; Michael Stone, M & Tommy Edwards, T
Object Type: Article
System: The UNT Digital Library
Time-Dependent and Time-Integrated Angular Analysis of B -> phi Ks pi0 and B -> phi K+ pi- (open access)

Time-Dependent and Time-Integrated Angular Analysis of B -> phi Ks pi0 and B -> phi K+ pi-

We perform a time-dependent and time-integrated angular analysis of the B{sup 0} {yields} {psi}K*(892){sup 0}, {psi}K*{sub 2}(1430{sup 0}), and {psi}(K{pi}){sub S-wave}{sup 0} decays with the final sample of about 465 million B{bar B} pairs recorded with the BABAR detector. Overall, twelve parameters are measured for the vector-vector decay, nine parameters for the vector-tensor decay, and three parameters for the vector-scalar decay, including the branching fractions, CP-violation parameters, and parameters sensitive to final state interaction. We use the dependence on the K{pi} invariant mass of the interference between the scalar and vector or tensor components to resolve discrete ambiguities of the strong and weak phases. We use the time-evolution of the B {yields} {psi}K{sub S}{sup 0}{pi}{sup 0} channel to extract the CP-violation phase difference {Delta}{phi}{sub 00} = 0.28 {+-} 0.42 {+-} 0.04 between the B and {bar B} decay amplitudes. When the B {yields} {psi}K{sup {+-}}{pi}{sup {-+}} channel is included, the fractions of longitudinal polarization f{sub L} of the vector-vector and vector-tensor decay modes are measured to be 0.494 {+-} 0.034 {+-} 0.013 and 0.901{sub -0.058}{sup +0.046} {+-} 0.037, respectively. This polarization pattern requires the presence of a helicity-plus amplitude in the vector-vector decay from a presently unknown source.
Date: August 4, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y; Lees, J.P. & Poireau, V.
Object Type: Article
System: The UNT Digital Library
Expanding Conventional Seismic Stratigrphy into the Multicomponent Seismic Domain (open access)

Expanding Conventional Seismic Stratigrphy into the Multicomponent Seismic Domain

Multicomponent seismic data are composed of three independent vector-based seismic wave modes. These wave modes are, compressional mode (P), and shear modes SV and SH. The three modes are generated using three orthogonal source-displacement vectors and then recorded using three orthogonal vector sensors. The components travel through the earth at differing velocities and directions. The velocities of SH and SV as they travel through the subsurface differ by only a few percent, but the velocities of SV and SH (Vs) are appreciably lower than the P-wave velocity (Vp). The velocity ratio Vp/Vs varies by an order of magnitude in the earth from a value of 15 to 1.5 depending on the degree of sedimentary lithification. The data used in this study were acquired by nine-component (9C) vertical seismic profile (VSP), using three orthogonal vector sources. The 9C vertical seismic profile is capable of generating P-wave mode and the fundamental S-wave mode (SH-SH and SV-SV) directly at the source station and permits the basic components of elastic wavefield (P, SH-SH and SV-SV) to be separated from one another for the purposes of imaging. Analysis and interpretations of data from the study area show that incident full-elastic seismic wavefield is capable of …
Date: August 31, 2008
Creator: Aluka, Innocent J.
Object Type: Report
System: The UNT Digital Library
Optical Technologies for Arming, Safing, Fuzing and Firing IV, SPIE, San Diego, CA 8/11/2008 (open access)

Optical Technologies for Arming, Safing, Fuzing and Firing IV, SPIE, San Diego, CA 8/11/2008

The design and packaging of laser-optical system was tested to harsh environments outside lab conditions and post mortem activities will be discussed. Previously, custom mounts and bonded optical assemblies were environmentally tested to ensure their survivability. The results verified the sub-assemblies would enable the design of a laser-optical initiation system that could be fielded for use in extreme conditions. The design package, which utilized the proven opto-mechanical sub-assemblies, was then tested to the same levels as the sub-assemblies. The test regiment encompassed the harshest environments currently utilized. Temperature tests were performed ranging from a maximum of +75 degrees C to a minimum of -55 degrees C, allowing for two hour soak at each temperature set point. Vibration tests were performed to a maximum level of 15.5 grms for forty seconds in each of three critical axes. Shock tests were performed to a maximum impulse level of 5700 G’s for the sub-assemblies with a 1.1 millisecond long pulse; whereas the packaged laser system maximum level reached was 3700 G’s at 1.1 millisecond long pulse. The laser-optical assembly was visually inspected and functionally tested before and after each test to verify survival. As designed, the system covers were laser welded shut for …
Date: August 11, 2008
Creator: Bright, Michelle
Object Type: Article
System: The UNT Digital Library
CdMnTe in X-ray and Gamma-ray Detection: Potential Applications (open access)

CdMnTe in X-ray and Gamma-ray Detection: Potential Applications

CdMnTe can be a good candidate for gamma-ray detection because of its wide band-gap, high resistivity, and good electro-transport properties. Further, the ability to grow CMT crystals at relatively low temperatures ensures a high yield for manufacturing detectors with good compositional uniformity and few impurities. Our group at Brookhaven National Laboratory is investigating several CMT crystals, selecting a few of them to make detectors. In this paper, we discuss our initial characterization of these crystals and describe our preliminary results with a gamma-ray source.
Date: August 11, 2008
Creator: Cui, Y.; Bolotnikov, A.; Hossain, A.; Camarda, G.; Mycielski, A.; Yang, G. et al.
Object Type: Article
System: The UNT Digital Library
Poroelastic modeling of fracture-seismic wave interaction (open access)

Poroelastic modeling of fracture-seismic wave interaction

Rock containing a compliant, fluid-filled fracture can be viewed as one case of heterogeneous poroelastic media. When this fracture is subjected to seismic waves, a strong contrast in the elastic stiffness between the fracture itself and the background can result in enhanced grain-scale local fluid flow. Because this flow--relaxing the pressure building up within the fracture--can increase the dynamic compliance of the fracture and change energy dissipation (attenuation), the scattering of seismic waves can be enhanced. Previously, for a flat, infinite fracture, we derived poroelastic seismic boundary conditions that describe the relationship between a finite jump in the stress and displacement across a fracture, expressed as a function of the stress and displacement at the boundaries. In this paper, we use these boundary conditions to determine frequency-dependent seismic wave transmission and reflection coefficients. Fluid-filled fractures with a range of mechanical and hydraulic properties are examined. From parametric studies, we found that the hydraulic permeability of a fracture fully saturated with water has little impact on seismic wave scattering. In contrast, the seismic response of a partially water-saturated fracture and a heterogeneous fracture filled with compliant liquid (e.g., supercritical CO{sub 2}) depended on the fracture permeability.
Date: August 15, 2008
Creator: Nakagawa, Seiji
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for the 100-F-46, 119-F Stack Sampling French Drain, Waste Site Reclassification Form 2008-021 (open access)

Remaining Sites Verification Package for the 100-F-46, 119-F Stack Sampling French Drain, Waste Site Reclassification Form 2008-021

The 100-F-46 french drain consisted of a 1.5 to 3 m long, vertically buried, gravel-filled pipe that was approximately 1 m in diameter. Also included in this waste site was a 5 cm cast-iron pipeline that drained condensate from the 119-F Stack Sampling Building into the 100-F-46 french drain. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: August 8, 2008
Creator: Capron, J. M.
Object Type: Report
System: The UNT Digital Library
Effects of vibrational motion on core-level spectra of prototype organic molecules (open access)

Effects of vibrational motion on core-level spectra of prototype organic molecules

A computational approach is presented for prediction and interpretation of core-level spectra of complex molecules. Applications are presented for several isolated organic molecules, sampling a range of chemical bonding and structural motifs. Comparison with gas phase measurements indicate that spectral lineshapes are accurately reproduced both above and below the ionization potential, without resort to ad hoc broadening. Agreement with experiment is significantly improved upon inclusion of vibrations via molecular dynamics sampling. We isolate and characterize spectral features due to particular electronic transitions enabled by vibrations, noting that even zero-point motion is sufficient in some cases.
Date: August 21, 2008
Creator: Uejio, Janel S.; Schwartz, Craig P.; Saykally, Richard J. & Prendergast, David
Object Type: Article
System: The UNT Digital Library
Measurement of B \to X \gamma Decays and Determination of |V_{td}/V_{ts}| (open access)

Measurement of B \to X \gamma Decays and Determination of |V_{td}/V_{ts}|

Using a sample of 383 million B{bar B} events collected by the BABAR experiment, they measure sums of seven exclusive final states B {yields} X{sub d(s)}{gamma}, where X{sub d}(X{sub s}) is a non-strange (strange) charmless hadronic system in the mass range 0.6-1.8 GeV/c{sup 2}. After correcting for unmeasured decay modes in this mass range, they obtain a branching fraction for b {yields} d{gamma} of (7.2 {+-} 2.7(stat.) {+-} 2.3(syst.)) x 10{sup -6}. Taking the ratio of X{sub d} to X{sub s} they find {Lambda}(b {yields} d{gamma})/{Lambda}(b {yields} s{gamma}) = 0.033 {+-} 0.013(stat.) {+-} 0.009(syst.), from which they determine |V{sub td}/V{sub ts}| = 0.177 {+-} 0.043.
Date: August 5, 2008
Creator: Collaboration, The BABAR & Aubert, B.
Object Type: Article
System: The UNT Digital Library
Navy fuel cell demonstration project. (open access)

Navy fuel cell demonstration project.

This is the final report on a field evaluation by the Department of the Navy of twenty 5-kW PEM fuel cells carried out during 2004 and 2005 at five Navy sites located in New York, California, and Hawaii. The key objective of the effort was to obtain an engineering assessment of their military applications. Particular issues of interest were fuel cell cost, performance, reliability, and the readiness of commercial fuel cells for use as a standalone (grid-independent) power option. Two corollary objectives of the demonstration were to promote technological advances and to improve fuel performance and reliability. From a cost perspective, the capital cost of PEM fuel cells at this stage of their development is high compared to other power generation technologies. Sandia National Laboratories technical recommendation to the Navy is to remain involved in evaluating successive generations of this technology, particularly in locations with greater environmental extremes, and it encourages their increased use by the Navy.
Date: August 1, 2008
Creator: Black, Billy D. & Akhil, Abbas Ali
Object Type: Report
System: The UNT Digital Library
Search for Supersymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV Using the Trilepton Signature of Chargino-Neutralino Production (open access)

Search for Supersymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV Using the Trilepton Signature of Chargino-Neutralino Production

None
Date: August 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
OpenCV and TYZX : video surveillance for tracking. (open access)

OpenCV and TYZX : video surveillance for tracking.

As part of the National Security Engineering Institute (NSEI) project, several sensors were developed in conjunction with an assessment algorithm. A camera system was developed in-house to track the locations of personnel within a secure room. In addition, a commercial, off-the-shelf (COTS) tracking system developed by TYZX was examined. TYZX is a Bay Area start-up that has developed its own tracking hardware and software which we use as COTS support for robust tracking. This report discusses the pros and cons of each camera system, how they work, a proposed data fusion method, and some visual results. Distributed, embedded image processing solutions show the most promise in their ability to track multiple targets in complex environments and in real-time. Future work on the camera system may include three-dimensional volumetric tracking by using multiple simple cameras, Kalman or particle filtering, automated camera calibration and registration, and gesture or path recognition.
Date: August 1, 2008
Creator: He, Jim; Spencer, Andrew & Chu, Eric
Object Type: Report
System: The UNT Digital Library
Combination of CDF and D0 results on the W boson mass and width (open access)

Combination of CDF and D0 results on the W boson mass and width

The results on the direct measurements of the W-boson mass and width, based on the data collected by the Tevatron experiments CDF and D{sup -} at Fermilab are summarized and combined. The CDF Run-0 (1988-1889) and Run-I (1992-1995) results have been re-averaged using the BLUE method and combined with Run-I D{sup -} results and the latest published results from CDF taken from the first period of Run-II (2001-2004). The results are corrected to have consistency between the parton distribution functions and electroweak parameters. The resulting Tevatron averages for the mass and total decay width of the W boson are: M{sub W} = 80432 {+-} 39 MeV and {Lambda}{sub W} = 2056 {+-} 62 MeV. The inclusion of a preliminary Run-II measurement of {Lambda}{sub W} from D{sup -}0 gives {Lambda}{sub W} = 2050 {+-} 58 MeV.
Date: August 1, 2008
Creator: Group, Tevatron Electroweak Working
Object Type: Report
System: The UNT Digital Library
SAVANNAH RIVER SITE ENVIRONMENTAL REPORT FOR 2007 (open access)

SAVANNAH RIVER SITE ENVIRONMENTAL REPORT FOR 2007

The Savannah River Site Environmental Report for 2007 (WSRC-STI-2008-00057) prepared for the US Department of Energy (DOE) according to requirements of DOE Order 231.1A, 'Environment, Safety and Health Reporting', and DOE Order 5400.5, 'Radiation Protection of the Public and Environment'. The report's purpose is to: (1) present summary environmental data that characterize site environmental management performance; (2) confirm compliance with environmental standards and requirements; (3) highlight significant programs and efforts; (4) assess the impact of SRS operations on the public and the environment.
Date: August 27, 2008
Creator: Mamatey, A
Object Type: Report
System: The UNT Digital Library
Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) Data Loading Manual (open access)

Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) Data Loading Manual

The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) is a software application developed for performing a complete probabilistic risk assessment (PRA) using a personal computer. SAPHIRE is primarily funded by the U.S. Nuclear Regulatory Commission (NRC) and developed by the Idaho National Laboratory. This report is intended to assist the user to enter PRA data into the SAPHIRE program using the built-in MAR-D ASCII-text file data transfer process. Towards this end, a small sample database is constructed and utilized for demonstration. Where applicable, the discussion includes how the data processes for loading the sample database relate to the actual processes used to load a larger PRA models. The procedures described herein were developed for use with SAPHIRE Version 6.0 and Version 7.0. In general, the data transfer procedures for version 6 and 7 are the same, but where deviations exist, the differences are noted. The guidance specified in this document will allow a user to have sufficient knowledge to both understand the data format used by SAPHIRE and to carry out the transfer of data between different PRA projects.
Date: August 1, 2008
Creator: Smith, C. L.; Kvarfordt, K. J. & Wood, S. T.
Object Type: Report
System: The UNT Digital Library
Higher Order Model Power Calculation of the 56 MHz SRF Cavity (open access)

Higher Order Model Power Calculation of the 56 MHz SRF Cavity

In this report, the HOM power dissipated to the load in the 56 MHz RF cavity is calculated. The HOM frequencies and Q factors with the inserted HOM damper are obtained from the simulations by MWS and SLAC codes.
Date: August 1, 2008
Creator: Choi,E.
Object Type: Report
System: The UNT Digital Library
Measurement of CP-Violating Asymmetries in the B0->K+K-Ks Dalitz Plot (open access)

Measurement of CP-Violating Asymmetries in the B0->K+K-Ks Dalitz Plot

The authors present a preliminary measurement of CP-violation parameters in the decay B{sup 0} {yields} K{sup +}K{sup -}K{sub S}{sup 0}, using approximately 465 million B{bar B} events collected by the BABAR detector at SLAC. Reconstructing the neutral kaon as K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -} or K{sub S}{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, they analyze the Dalitz plot distribution and measure fractions to intermediate states. They extract CP parameters from the asymmetries in amplitudes and phases between B{sup 0} and {bar B}{sup 0} decays across the Dalitz plot. From a fit to the whole Dalitz plot, they measure {beta}{sub eff} = 0.44 {+-} 0.07 {+-} 0.02, A{sub CP} = 0.03 {+-} 0.07 {+-} 0.02, where the first uncertainties are statistical and the second ones are systematic. For decays to {phi}K{sub S}{sup 0}, they measure {beta}{sub eff} = 0.13 {+-} 0.13 {+-} 0.02, A{sub CP} = 0.14 {+-} 0.19 {+-} 0.02. For decays to f{sub 0}K{sub S}{sup 0}, they measure {beta}{sub eff} = 0.15 {+-} 0.13 {+-} 0.03, A{sub CP} = 0.01 {+-} 0.26 {+-} 0.07. From a fit to the region of the Dalitz plot with m{sub K{sup +}K{sup -}} > 1.1 GeV/c{sup 2}, they measure {beta}{sub eff} = …
Date: August 7, 2008
Creator: Kim, H
Object Type: Article
System: The UNT Digital Library
Systems Analysis Programs for Hands-on Intergrated Reliability Evaluations (SAPHIRE) Summary Manual (open access)

Systems Analysis Programs for Hands-on Intergrated Reliability Evaluations (SAPHIRE) Summary Manual

The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) is a software application developed for performing a complete probabilistic risk assessment (PRA) using a personal computer (PC) running the Microsoft Windows operating system. SAPHIRE is primarily funded by the U.S. Nuclear Regulatory Commission (NRC) and developed by the Idaho National Laboratory (INL). INL's primary role in this project is that of software developer and tester. However, INL also plays an important role in technology transfer by interfacing and supporting SAPHIRE users, who constitute a wide range of PRA practitioners from the NRC, national laboratories, the private sector, and foreign countries. SAPHIRE can be used to model a complex system’s response to initiating events and quantify associated consequential outcome frequencies. Specifically, for nuclear power plant applications, SAPHIRE can identify important contributors to core damage (Level 1 PRA) and containment failure during a severe accident which lead to releases (Level 2 PRA). It can be used for a PRA where the reactor is at full power, low power, or at shutdown conditions. Furthermore, it can be used to analyze both internal and external initiating events and has special features for transforming an internal events model to a model for external events, …
Date: August 1, 2008
Creator: Smith, C. L.
Object Type: Report
System: The UNT Digital Library
Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays (open access)

Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays

The authors present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} K{sup +}{pi}{sup -}, B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and B{sup 0} {yields} K{sup 0}{pi}{sup 0}. This update includes all data taken at the {Upsilon}(4S) resonance by the BABAR experiment at the asymmetric PEP-II B-meson factory at SLAC, corresponding to 467 {+-} 5 million B{bar B} pairs. They find S{sub {pi}{pi}} = -0.68 {+-} 0.10 {+-} 0.03, C{sub {pi}{pi}} = -0.25 {+-} 0.08 {+-} 0.02, {Alpha}{sub K{sub {pi}}} = -0.107 {+-} 0.016{sub -0.004},{sup +0.006}, C{sub {pi}{sup 0}{pi}{sup 0}} = -0.43 {+-} 0.26 {+-} 0.05, {Beta}(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) = (1.83 {+-} 0.21 {+-} 0.13) x 10{sup -6}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup 0}) = (10.1 {+-} 0.6 {+-} 0.4) x 10{sup -6}, where the first error is statistical and the second is systematic. They observe CP violation with a significance of 6.7{sigma} in B{sup 0} {yields} {pi}{sup -} and 6.1{sigma} in B{sup 0} {yields} K{sup +}{pi}{sup -}. Constraints on the Unitarity Triangle angle {alpha} are determined from the isospin relation between all B {yields} {pi}{pi} rates and asymmetries.
Date: August 1, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Multiple-Coincidence Active Neutron Interrogation of Fissionable Materials (open access)

Multiple-Coincidence Active Neutron Interrogation of Fissionable Materials

Using a beam of tagged 14.1 MeV neutrons to probe for the presence of fissionable materials, we have measured n-γ-γ coincidences from depleted uranium (DU). The multiple coincidence rate is substantially above that measured from lead, tungsten, and iron. The presence of coincidences involving delayed gammas in the DU time spectra provides a signature for fissionable materials that is distinct from non-fissionable ones. In addition, the information from the tagged neutron involved in the coincidence gives the position of the fissionable material in all three dimensions. The result is an imaging probe for fissionable materials that is more compact and that produces much less radiation than other solutions.
Date: August 6, 2008
Creator: J.P. Hurley, R.P. Keegan, J.R. Tinsley, R. Trainham, and S.C. Wilde
Object Type: Article
System: The UNT Digital Library