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Complexity and Synchronization

Description: This article discusses complexity and synchronization in decision making and information transmission.
Date: August 14, 2009
Creator: Turalska, Malgorzata; Lukovic, Mirko; West, Bruce J. & Grigolini, Paolo
Partner: UNT College of Arts and Sciences
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

Theoretical Overview on Recent Developments in Transverse Spin Physics

Description: Transverse-spin physics has been very active and rapidly developing in the last few years. In this talk, I will briefly summarize recent theoretical developments, focusing on the associated QCD dynamics in transverse spin physics.
Date: January 14, 2009
Creator: Yuan, Feng
Partner: UNT Libraries Government Documents Department
open access

TTF HOM Data Analysis with Curve Fitting Method

Description: To investigate the possibility of using HOM signals induced in SC cavities as beam and cavity diagnostics, narrow band (20 MHz) data was recorded around the strong TE111-6(6{pi}/9-like) dipole modes (1.7 GHz) in the 40 L-band (1.3 GHz) cavities at the DESY TTF facility. The analyses of these data have so far focused on using a Singular Value Decomposition (SVD) technique to correlate the signals with each other and data from conventional BPMs to show the dipole signals provide an alternate mean… more
Date: July 14, 2009
Creator: Pei, S.; Adolphsen, C.; Li, Z.; Bane, K. & Smith, J.
Partner: UNT Libraries Government Documents Department
open access

Sensor Development and Readout Prototyping for the STAR Pixel Detector

Description: The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) is designing a new vertex detector. The purpose of this upgrade detector is to provide high resolution pointing to allow for the direct topological reconstruction of heavy flavor decays such as the D{sup 0} by finding vertices displaced from the collision vertex by greater than 60 microns. We are using Monolithic Active Pixel Sensor (MAPS) as the sensor technology and have a coupled sensor development and readout system plan that… more
Date: January 14, 2009
Creator: Greiner, L.; Anderssen, E.; Matis, H. S.; Ritter, H. G.; Stezelberger, T.; Szelezniak, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Improved Measurement of B^ \to\rho^ \rho^0 and Determination of the Quark-Mixing Phase Angle~\alpha

Description: The authors present improved measurements of the branching fraction {Beta}, the longitudinal polarization fraction f{sub L}, and the direct CP asymmetry A{sub CP} in the B meson decay channel B{sup +} {yields} {rho}{sup +}{rho}{sup 0}. The data sample was collected with the BABAR detector at SLAC. The results are {Beta}(B{sup +} {yields} {rho}{sup +}{rho}{sup 0}) = (23.7 {+-} 1.4 {+-} 1.4) x 10{sup -6}, f{sub L} = 0.950 {+-} 0.015 {+-} 0.006, and A{sub CP} = -0.054 {+-} 0.055 {+-} 0.010, where … more
Date: July 14, 2009
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Partner: UNT Libraries Government Documents Department
open access

Highly 15N-Enriched Chondritic Clasts in the Isheyevo Meteorite

Description: The metal-rich carbonaceous chondrites (CB and CH) have the highest whole-rock {sup 15}N enrichment ({delta}{sup 15}N up to +1500{per_thousand}), similar to {delta}{sup 15}N values reported in micron-sized regions (hotspots) of Interplanetary Dust Particles (IDPs) of possibly cometary origin and fine-grained matrices of unmetamorphosed chondrites. These {sup 15}N-rich hotspots are commonly attributed to low-temperature ion-molecule reactions in the protosolar molecular cloud or in the outer par… more
Date: January 14, 2009
Creator: Bonal, L; Huss, G R; Krot, A N; Nagashima, K; Ishii, H A; Bradley, J P et al.
Partner: UNT Libraries Government Documents Department
open access

Molecular uranates - laser synthesis of uranium oxide anions in the gas phase

Description: Laser ablation of solid UO{sub 3} or (NH{sub 4}){sub 2}U{sub 2}O{sub 7} yielded in the gas phase molecular uranium oxide anions with compositions ranging from [UO{sub n}]{sup -} (n = 2-4) to [U{sub 14}O{sub n}]{sup -} (n = 32-35), as detected by Fourier transform ion cyclotron resonance mass spectrometry. The cluster series [U{sub x}O{sub 3x}]{sup -} for x {le} 6 and various [U{sub x}O{sub 3x-y}]{sup -}, in which y increased with increasing x, could be identified. A few anions with H atoms were… more
Date: December 14, 2009
Creator: Marcalo, Joaquim; Santos, Marta; Pires de Matos, Antonio & Gibson, John K
Partner: UNT Libraries Government Documents Department
open access

Radioisotope Electric Propulsion for Deep Space Sample Return

Description: The need to answer basic questions regarding the origin of the Solar System will motivate robotic sample return missions to destinations like Pluto, its satellite Charon, and objects in the Kuiper belt. To keep the mission duration short enough to be of interest, sample return from objects farther out in the Solar System requires increasingly higher return velocities. A sample return mission involves several complicated steps to reach an object and obtain a sample, but only the interplanetary r… more
Date: July 14, 2009
Creator: Noble, Robert J.
Partner: UNT Libraries Government Documents Department
open access

Simulation Studies of the X-Ray Free-Electron Laser Oscillator

Description: Simulations of the x-ray free-electron laser (FEL) oscillator are presented that include transverse effects and realistic Bragg crystal properties with the two-dimensional code GINGER. In the present cases considered the radiation divergence is much narrower than the crystal acceptance, and the numerical algorithm can be simplified by ignoring the finite angular bandwidth of the crystal. In this regime GINGER shows that the saturated x-ray pulses have 109 photons and are nearly Fourier-limited … more
Date: August 14, 2009
Creator: Lindberg, R. R.; Shyd'ko, Y.; Kim, K. J. & Fawley, W. M.
Partner: UNT Libraries Government Documents Department
open access

LESSONS FROM THE RED BEADS

Description: No Description Available.
Date: April 14, 2009
Creator: SS, PREVETTE
Partner: UNT Libraries Government Documents Department
open access

Chemical pressure and hidden one-dimensional behavior in rare earth tri-telluride

Description: We report on the first optical measurements of the rare-earth tri-telluride charge-density-wave systems. Our data, collected over an extremely broad spectral range, allow us to observe both the Drude component and the single-particle peak, ascribed to the contributions due to the free charge carriers and to the charge-density-wave gap excitation, respectively. The data analysis displays a diminishing impact of the charge-density-wave condensate on the electronic properties with decreasing latti… more
Date: December 14, 2009
Creator: Sacchetti, A.; Degiorgi, L.; Giamarchi, T.; Ru, N. & Fisher, I. R.
Partner: UNT Libraries Government Documents Department
open access

Pressure Dependence of the Charge-Density-Wave Gap in Rare-Earth Tri-Tellurides

Description: We investigate the pressure dependence of the optical properties of CeTe{sub 3}, which exhibits an incommensurate charge-density-wave (CDW) state already at 300 K. Our data are collected in the mid-infrared spectral range at room temperature and at pressures between 0 and 9 GPa. The energy for the single particle excitation across the CDW gap decreases upon increasing the applied pressure, similarly to the chemical pressure by rare-earth substitution. The broadening of the bands upon lattice co… more
Date: December 14, 2009
Creator: Sacchetti, A.; /Zurich, ETH; Arcangeletti, E.; Perucchi, A.; Baldassarre, L.; Postorino, P. et al.
Partner: UNT Libraries Government Documents Department
open access

The Open Source Stochastic Building Simulation Tool SLBM and Its Capabilities to Capture Uncertainty of Policymaking in the U.S. Building Sector

Description: The increasing concern about climate change as well as the expected direct environmental economic impacts of global warming will put considerable constraints on the US building sector, which consumes roughly 48percent of the total primary energy, making it the biggest single source of CO2 emissions. It is obvious that the battle against climate change can only be won by considering innovative building approaches and consumer behaviors and bringing new, effective low carbon technologies to the b… more
Date: May 14, 2009
Creator: Stadler, Michael; Marnay, Chris; Azevedo, Ines Lima; Komiyama, Ryoichi & Lai, Judy
Partner: UNT Libraries Government Documents Department
open access

A structure zone diagram including plasma based deposition and ion etching

Description: An extended structure zone diagram is proposed that includes energetic deposition, characterized by a large flux of ions typical for deposition by filtered cathodic arcs and high power impulse magnetron sputtering. The axes are comprised of a generalized homologous temperature, the normalized kinetic energy flux, and the net film thickness, which can be negative due to ion etching. It is stressed that the number of primary physical parameters affecting growth by far exceeds the number of availa… more
Date: October 14, 2009
Creator: Anders, Andre
Partner: UNT Libraries Government Documents Department
open access

Fel Gain Length and Taper Measurements at Lcls

Description: We present experimental studies of the gain length and saturation power level from 1.5 nm to 1.5 Angstroms at the Linac Coherent Light Source (LCLS). By disrupting theFEL process with an orbit kick, we are able to measure the X-ray intensity as a function of undulator length. This kick method is cross-checked with the method of removing undulator sections. We also study the FEL-induced electron energy loss after saturation to determine the optimal taper of the undulator K values. The experiment… more
Date: August 14, 2009
Creator: Ratner, D.; Fawley, W. M.; Brachmann, A.; Decker, F. J.; Ding, Y.; Dowell, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Pressure dependence of the optical properties of the charge-density-wave compound LaTe2

Description: We report the pressure dependence of the optical response of LaTe{sub 2}, which is deep in the charge-density-wave (CDW) ground state even at 300 K. The reflectivity spectrum is collected in the mid-infrared spectral range at room temperature and at pressures between 0 and 7 GPa. We extract the energy scale due to the single particle excitation across the CDW gap and the Drude weight. We establish that the gap decreases upon compressing the lattice, while the Drude weight increases. This signal… more
Date: December 14, 2009
Creator: Lavagnini, M.; Sacchetti, A.; Degiorgi, L.; Arcangeletti, E.; Baldassarre, L.; Postorino, P. et al.
Partner: UNT Libraries Government Documents Department
open access

B meson decays to charmless meson pairs containing eta or eta'

Description: The authors present updated measurements of the branching fractions for B{sup 0} meson decays to {eta}K{sup 0}, {eta}{eta}, {eta}{phi}, {eta}{omega}, {eta}{prime}K{sup 0}, {eta}{prime}{eta}{prime}, {eta}{prime}, {phi}, and {eta}{prime}{omega} and branching fractions and CP-violating charge asymmetries for B{sup +} decays to {eta}{pi}{sup +}, {eta}K{sup +}, {eta}{prime}{pi}{sup +}, and {eta}{prime} K{sup +}. The data represent the full dataset of 467 x 10{sup 6} B{bar B} pairs collected with the… more
Date: December 14, 2009
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

THE SECOND STAGE OF FERMI@ELETTRA: A SEEDED FEL IN THE SOFT X-RAY SPECTRAL RANGE

Description: The second stage of the FERMI FEL, named FEL-2, is based on the principle of high-gain harmonic generation and relies on a double-seeded cascade. Recent developments stimulated a revision of the original setup, which was designed to cover the spectral range between 40 and 10 nm. The numerical simulations we present here show that the nominal (expected) electron-beam performance allows extension of the FEL spectral range down to 4 nm. A significant amount of third harmonic power can be also expe… more
Date: August 14, 2009
Creator: Allaria, E.; DeNinno, G. & Fawley, W. M.
Partner: UNT Libraries Government Documents Department
open access

Measurements of Black Carbon Particles Chemical, Physical, and Optical Properties

Description: Accurate measurements of the chemical, physical, and optical properties of aerosol particles containing black carbon are necessary to improve current estimates of the radiative forcing in the atmosphere. A collaborative research effort between Aerodyne Research, Inc. and Boston College has focused on conducting field and laboratory experiments on carbonaceous particles and the development and characterization of new particulate instrumentation. This presentation will focus on the chemical, phys… more
Date: December 14, 2009
Creator: Onasch, T.B.; Sedlacek, A.; Cross, E. S.; Davidovits, P.; Worsnop, D. R.; Ahern, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Toward Accurate Reaction Energetics for Molecular Line Growth at Surface: Quantum Monte Carlo and Density Functional Theory Calculations

Description: We revisit the molecular line growth mechanism of styrene on the hydrogenated Si(001) 2x1 surface. In particular, we investigate the energetics of the radical chain reaction mechanism by means of diffusion quantum Monte Carlo (QMC) and density functional theory (DFT) calculations. For the exchange correlation (XC) functional we use the non-empirical generalized-gradient approximation (GGA) and meta-GGA. We find that the QMC result also predicts the intra dimer-row growth of the molecular line o… more
Date: October 14, 2009
Creator: Kanai, Y & Takeuchi, N
Partner: UNT Libraries Government Documents Department
open access

Magnetic properties of the charge density wave compounds RTe3, R=Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er & Tm

Description: The antiferromagnetic transition is investigated in the rare-earth (R) tritelluride RTe{sub 3} family of charge density wave (CDW) compounds via specific heat, magnetization and resistivity measurements. Observation of the opening of a superzone gap in the resistivity of DyTe{sub 3} indicates that additional nesting of the reconstructed Fermi surface in the CDW state plays an important role in determining the magnetic structure.
Date: December 14, 2009
Creator: Ru, N.; Chu, J.-H.; Fisher, I.R. & /Stanford U., Geballe Lab.
Partner: UNT Libraries Government Documents Department
open access

De Haas-van Alphen oscillations in the charge-density wave compound lanthanum tritelluride (LaTe3)

Description: De Haas-van Alphen oscillations were measured in lanthanum tritelluride (LaTe{sub 3}) to probe the partially gapped Fermi surface resulting from charge density wave (CDW) formation. Three distinct frequencies were observed, one of which can be correlated with a FS sheet that is unaltered by CDW formation. The other two frequencies arise from FS sheets that have been reconstructed in the CDW state.
Date: December 14, 2009
Creator: Ru, N.; Borzi, R. A.; Rost, A.; Mackenzie, A. P.; Laverock, J.; Dugdale, S. B. et al.
Partner: UNT Libraries Government Documents Department
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