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Recent charm mixing results from BABAR, Belle, and CDF

Description: A summary of the results of several recent studies of charm mixing is presented. A number of different methods were used, including the measurement of lifetime ratios for final states of different CP, time dependence of wrong-sign hadronic decays, fits to time-dependent Dalitz plots, and searches for wrong-sign semi-leptonic decays. Taken together, they suggest mixing is of order 1%. The status of searches for indirect CP violation is also reported.
Date: February 2, 2009
Creator: Charles, M.J. & /SLAC, /Iowa U.
Partner: UNT Libraries Government Documents Department
open access

Time Reversal Violation

Description: This talk briefly reviews three types of time-asymmetry in physics, which I classify as universal, macroscopic and microscopic. Most of the talk is focused on the latter, namely the violation of T-reversal invariance in particle physics theories. In sum tests of microscopic T-invariance, or observations of its violation, are limited by the fact that, while we can measure many processes, only in very few cases can we construct a matched pair of process and inverse process and observe it with suf… more
Date: January 27, 2009
Creator: Quinn, H.
Partner: UNT Libraries Government Documents Department
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Technical Risk Rating of DOE Environmental Projects - 9153

Description: The U.S. Department of Energy's Office of Environmental Management (DOE-EM) was established to achieve the safe and compliant disposition of legacy wastes and facilities from defense nuclear applications. The scope of work is diverse, with projects ranging from single acquisitions to collections of projects and operations that span several decades and costs from hundreds of millions to billions US$. The need to be able to manage and understand the technical risks from the project to senior mana… more
Date: February 11, 2009
Creator: Cercy, Michael; Fayfich, Ronald & Schneider, Steven
Partner: UNT Libraries Government Documents Department
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Measurement of the t anti-t production cross section and top quark mass extraction using dilepton events in p anti-p collisions

Description: We present a measurement of the top quark pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using approximately 1 fb{sup -1} of data collected with the D0 detector. We consider decay channels containing two high p{sub T} charged leptons where one lepton is identified as an electron or a muon while the other lepton can be an electron, a muon or a hadronically decaying {tau} lepton. For a mass of the top quark of 170 GeV, the measured cross section is 7.5{sub -1.0}{sup… more
Date: January 1, 2009
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

High Resolution Simulation of Beam Dynamics in Electron Linacs for Free Electron Lasers

Description: In this paper we report on large scale multi-physics simulation of beam dynamics in electron linacs for next generation free electron lasers (FELs). We describe key features of a parallel macroparticle simulation code including three-dimensional (3D) space-charge effects, short-range structure wake fields, longitudinal coherent synchrotron radiation (CSR) wake fields, and treatment of radiofrequency (RF) accelerating cavities using maps obtained from axial field profiles. A macroparticle up-sam… more
Date: January 5, 2009
Creator: Ryne, R.D.; Venturini, M.; Zholents, A.A. & Qiang, J.
Partner: UNT Libraries Government Documents Department
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CHANGING THE SAFETY CULTURE IN HANFORD TANK FARMS

Description: In 2000 the Hanford Tank Farms had one of the worst safety records in the Department of Energy Complex. By the end of FY08 the safety performance of the workforce had turned completely around, resulting in one of the best safety records in the DOE complex for operations of its kind. This paper describes the variety of programs and changes that were put in place to accomplish such a dramatic turn-around. The U.S. Department of Energy's 586-square-mile Hanford Site in Washington State was establi… more
Date: January 6, 2009
Creator: MV, BERRIOCHOA & LJ, ALCALA
Partner: UNT Libraries Government Documents Department
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Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu

Description: The authors present measurements of the semileptonic decays B{sup -} {yields} D{sup 0} {tau}{sup -} {bar {nu}}{sub {tau}}, B{sup -} {yields} D*{sup 0} {tau}{sup -}{bar {nu}}{sub {tau}}, {bar B}{sup 0} {yields} D{sup +} {tau}{sup -} {bar {nu}}{sub {tau}}, and {bar B}{sup 0} {yields} D*{sup +} {tau}{sup -}{bar {nu}}{sub {tau}}, which are sensitive to non-Standard Model amplitudes in certain scenarios. The data sample consists of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected wit… more
Date: February 23, 2009
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Description: Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
Partner: UNT Libraries Government Documents Department
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Light-Front Holography and QCD Hadronization at the Amplitude Level

Description: Light-front holography allows hadronic amplitudes in the AdS/QCD fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. The AdS coordinate z is identified with an invariant light-front coordinate {zeta} which separates the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single-varia… more
Date: January 9, 2009
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
Partner: UNT Libraries Government Documents Department
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Energy Systems Integration Facility (ESIF) External Stakeholders Workshop

Description: On October 9, 2008, NREL hosted a workshop to provide an opportunity for external stakeholders to offer insights and recommendations on the design and functionality of DOE's planned Energy Systems Infrastructure Facility (ESIF). The goal was to ensure that the planning for the ESIF effectively addresses the most critical barriers to large-scale energy efficiency (EE) and renewable energy (RE) deployment. This technical report documents the ESIF workshop proceedings.
Date: January 1, 2009
Creator: Komomua, C.; Kroposki, B.; Mooney, D.; Stoffel, T.; Parsons, B.; Hammond, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Computer Simulations of Edge Effects in a Small-Area Mesa N-P Junction Diodes: Preprint

Description: In this work, computer simulations are used to determine the influence of edge conditions on the overall performance of mesa diodes under dark and illuminated conditions. In particular, we examine the effect of edge shape on the I-V characteristics of the diode.
Date: February 1, 2009
Creator: Appel, J.; Sopori, B. & Ravindra, N. M.
Partner: UNT Libraries Government Documents Department
open access

Comparisons of the MINOS Near and Far Detector Readout Systems at a Test Beam

Description: MINOS is a long baseline neutrino oscillation experiment that uses two detectors separated by 734 km. The readout systems used for the two detectors are different and have to be independently calibrated. To verify and make a direct comparison of the calibrated response of the two readout systems, test beam data were acquired using a smaller calibration detector. This detector was simultaneously instrumented with both readout systems and exposed to the CERN PS T7 test beam. Differences in the ca… more
Date: February 1, 2009
Creator: Cabrera, A.; U., /Oxford; Adamson, P.; London, /University Coll.; Barker, M.; U., /Oxford et al.
Partner: UNT Libraries Government Documents Department
open access

Beam Compression in Heavy-Ion Induction Linacs

Description: The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the Warm Dense Matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has been demonstrated in the LBNL Neutralized Drift Compression Experiment (NDCX) experiment with controlled ramps and forced neutralization. The achieved peak beam current and energy can be used… more
Date: January 1, 2009
Creator: Seidl, P. A.; Anders, A.; Bieniosek, F. M.; Barnard, J. J.; Calanog, J.; Chen, A. X. et al.
Partner: UNT Libraries Government Documents Department
open access

Dalitz Plot Analysis of B- -> D+ pi- pi-

Description: The author reports on a Dalitz plot analysis of B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -} decays, based on a sample of about 383 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They find the total branching fraction of the three-body decay: {Beta}(B{sup -} {yields} D{sup +} {pi}{sup -}{pi}{sup -}) = (1.08 {+-} 0.01 {+-} 0.05) x 10{sup -3}. the masses and widths of D*{sub 2}{sup 0} and D*{sub 0}{sup 0}, th… more
Date: January 29, 2009
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Metastable Supersymmetry Breaking and Multitrace Deformations of SQCD

Description: Metastable vacua in supersymmetric QCD in the presence of single and multitrace deformations of the superpotential are explored, with the aim of obtaining an acceptable phenomenology. The metastable vacua appear at one loop, have a broken R-symmetry, and a magnetic gauge group that is completely Higgsed. With only a single trace deformation, the adjoint fermions from the meson superfield are approximately massless at one loop, even though they are massive at tree level and R-symmetry is broken.… more
Date: February 23, 2009
Creator: Essig, Rouven; Fortin, Jean-Francois; Sinha, Kuver; Torroba, Gonzalo & Strassler, Matthew J.
Partner: UNT Libraries Government Documents Department
open access

Dynamic versus Static Hadronic Structure Functions

Description: 'Static' structure functions are the probabilistic distributions computed from the square of the light-front wavefunctions of the target hadron. In contrast, the 'dynamic' structure functions measured in deep inelastic lepton-hadron scattering include the effects of rescattering associated with the Wilson line. Initial- and final-state rescattering, neglected in the parton model, can have a profound effect in QCD hard-scattering reactions, producing single-spin asymmetries, diffractive deep ine… more
Date: January 9, 2009
Creator: Brodsky, Stanley J.
Partner: UNT Libraries Government Documents Department
open access

Scanning SQUID microscopy on polycrystalline SmFeAsO_{0.85} and NdFeAsO_{0.94}F_{0.06}

Description: The order parameter of the recently-discovered ferric arsenide family of superconductors remains uncertain. Some early experiments on polycrystalline samples suggested line nodes in the order parameter, however later experiments on single crystals have strongly supported fully-gapped superconductivity. An absence of nodes does not rule out unconventional order: {pi} phase shifts between the separate Fermi sheets and time-reversal symmetry-breaking components in the order parameter remain possib… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Moler, Kathryn A.; Huber, Martin E.; Ren, Zhi-An & Zhao, Zhong-Xian
Partner: UNT Libraries Government Documents Department
open access

Vector Unparticle Contributions to Lepton g-2

Description: The generic unparticle propagator may be modified in two ways. Breaking the conformal symmetry effectively adds a mass term to the propagator, while considering vacuum polarization corrections adds a width-like term. Both of these modifications result naturally from the coupling of the unparticle to standard model (SM) fields. We explore how these modifications to the propagator affect the calculation of the lepton anomalous magnetic moment using an integral approximation of the propagator that… more
Date: February 2, 2009
Creator: Conley, John A. & Gainer, James S.
Partner: UNT Libraries Government Documents Department
open access

Simulating SiD Calorimetry: Software Calibration Procedures and Jet Energy Resolution

Description: Simulated calorimeter performance in the SiD detector is examined. The software calibration procedures are described, as well as the perfect pattern recognition PFA reconstruction. Performance of the SiD calorimeters is summarized with jet energy resolutions from calorimetry only, perfect pattern recognition and the SiD PFA algorithm. Presented at LCWS08[1]. Our objective is to simulate the calorimeter performance of the SiD detector, with and without a Particle Flow Algorithm (PFA). Full Geant… more
Date: February 23, 2009
Creator: Cassell, Ron
Partner: UNT Libraries Government Documents Department
open access

ON THE IMPACT OF SUPER RESOLUTION WSR-88D DOPPLER RADAR DATA ASSIMILATION ON HIGH RESOLUTION NUMERICAL MODEL FORECASTS

Description: Assimilation of radar velocity and precipitation fields into high-resolution model simulations can improve precipitation forecasts with decreased 'spin-up' time and improve short-term simulation of boundary layer winds (Benjamin, 2004 & 2007; Xiao, 2008) which is critical to improving plume transport forecasts. Accurate description of wind and turbulence fields is essential to useful atmospheric transport and dispersion results, and any improvement in the accuracy of these fields will make cons… more
Date: January 11, 2009
Creator: Chiswell, S
Partner: UNT Libraries Government Documents Department
open access

DOWNSTREAM IMPACTS OF SLUDGE MASS REDUCTION VIA ALUMINUM DISSOLUTION ON DWPF PROCESSING OF SAVANNAH RIVER SITE HIGH LEVEL WASTE - 9382

Description: The SRS sludge that was to become a major fraction of Sludge Batch 5 (SB5) for the Defense Waste Processing Facility (DWPF) contained a large fraction of H-Modified PUREX (HM) sludge, containing a large fraction of aluminum compounds that could adversely impact the processing and increase the vitrified waste volume. It is beneficial to reduce the non-radioactive fraction of the sludge to minimize the number of glass waste canisters that must be sent to a Federal Repository. Removal of aluminum … more
Date: January 14, 2009
Creator: Pareizs, J; Cj Bannochie, C; Michael Hay, M & Daniel McCabe, D
Partner: UNT Libraries Government Documents Department
open access

Light-Induced Passivation of Si by Iodine Ethanol Solution: Preprint

Description: We report on our observations of light-activated passivation of silicon surfaces by iodine-ethanol solution.
Date: February 1, 2009
Creator: Sopori, B.; Rupnowski, P.; Appel, J.; Guhaabiswas, D. & Anderson-Jackson, L.
Partner: UNT Libraries Government Documents Department
open access

Plasma"anti-assistance" and"self-assistance" to high power impulse magnetron sputtering

Description: A plasma assistance system was investigated with the goal to operate high power impulse magnetron sputtering (HiPIMS) at lower pressure than usual, thereby to enhance the utilization of the ballistic atoms and ions with high kinetic energy in the film growth process. Gas plasma flow from a constricted plasma source was aimed at the magnetron target. Contrary to initial expectations, such plasma assistance turned out to be contra-productive because it led to the extinction of the magnetron disch… more
Date: January 30, 2009
Creator: Anders, Andre & Yushkov, Georgy Yu.
Partner: UNT Libraries Government Documents Department
open access

Rare B Decays at Babar

Description: The author presents some of the most recent BABAR measurements for rare B decays. These include rate asymmetries in the B decays to K{sup (*)}l{sup +}l{sup -} and K{sup +}{pi}{sup -} and branching fractions in the B decays to l{sup +}{nu}{sub l}, K{sub 1}(1270){sup +}{pi}{sup -} and K{sub 1}(1400){sup +}{pi}{sup -}. The author also reports a search for the B{sup +} decay to K{sub S}{sup 0}K{sub S}{sup 0}{pi}{sup +}.
Date: January 12, 2009
Creator: Palombo, Fernando & Collaboration, for the BABAR
Partner: UNT Libraries Government Documents Department
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