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Of FFT-based convolutions and correlations, with application to solving Poisson's equation in an open rectangular pipe

Description: A new method is presented for solving Poisson's equation inside an open-ended rectangular pipe. The method uses Fast Fourier Transforms (FFTs)to perform mixed convolutions and correlations of the charge density with the Green function. Descriptions are provided for algorithms based on theordinary Green function and for an integrated Green function (IGF). Due to its similarity to the widely used Hockney algorithm for solving Poisson'sequation in free space, this capability can be easily implemen… more
Date: November 7, 2011
Creator: Ryne, Robert D.
Partner: UNT Libraries Government Documents Department
open access

Autonomous Sub-Pixel Satellite Track Endpoint Determination for Space Based Images

Description: An algorithm for determining satellite track endpoints with sub-pixel resolution in spaced-based images is presented. The algorithm allows for significant curvature in the imaged track due to rotation of the spacecraft capturing the image. The motivation behind the subpixel endpoint determination is first presented, followed by a description of the methodology used. Results from running the algorithm on real ground-based and simulated spaced-based images are shown to highlight its effectiveness. more
Date: March 7, 2011
Creator: Simms, L M
Partner: UNT Libraries Government Documents Department
open access

A Project to Design and Build the Magnets for a New Test Beamline, the ATF2, at KEK

Description: In order to achieve the high luminosity required at the proposed International Linear Collider (ILC), it is critical to focus the beams to nanometer size with the ILC Beam Delivery System, and to maintain the beams collisions with a nanometer-scale stability. To establish the technologies associated with this ultra-high precision beam handling, a special beamline has been designed and built as an extension of the existing extraction beamline of the Accelerator Test Facility at KEK, Japan. The A… more
Date: February 7, 2011
Creator: Spencer, Cherrill M.; /slac; Sugahara, Ryuhei; Masuzawa, Mika; /KEK, Tsukuba; Bolzon, Benoit et al.
Partner: UNT Libraries Government Documents Department
open access

Fireside Corrosion USC Steering

Description: Oxy-Fuel Fireside Research goals are: (1) Determine the effect of oxy-fuel combustion on fireside corrosion - (a) Flue gas recycle choice, Staged combustion ramifications, (c) JCOAL Collaboration; and (2) Develop methods to use chromia solubility in ash as an 'ash corrosivity' measurement - (a) Synthetic ashes at first, then boiler and burner rig ashes, (b) Applicable to SH/RH conditions.
Date: September 7, 2011
Creator: Holcomb, G. R. & Tylczak, J.
Partner: UNT Libraries Government Documents Department
open access

New Perspectives for QCD Physics at the LHC

Description: I review a number of topics where conventional wisdom relevant to hadron physics at the LHC has been challenged. For example, the initial-state and final-state interactions of the quarks and gluons entering perturbative QCD hard-scattering subprocesses lead to the breakdown of traditional concepts of factorization and universality for transverse-momentum-dependent observables at leading twist. These soft-gluon rescattering effect produce single-spin asymmetries, the breakdown of the Lam-Tung re… more
Date: February 7, 2011
Creator: Brodsky, Stanley J. & /SLAC /Stanford U. /Southern Denmark U., CP3-Origins
Partner: UNT Libraries Government Documents Department
open access

Extremely NA and CL Rich Chondrule AL3509 from the Allende Meteorite

Description: We report on the mineralogy, petrology, chemistry, oxygen isotopes, {sup 26}Al-{sup 26}Mg and {sup 36}Cl-{sup 36}S isotope systematics of the Allende chondrule Al3509 discovered and described by [1] and [2]. This spherical object ({approx}1cm {phi}) contains {approx}10% Na and 1% Cl, and nearly pure {sup 129}Xe [({sup 129}Xe/{sup 127}I) = 1.1 x 10{sup -4} (3)]. This high enrichment in halogens makes it of interest in searching for radiogenic {sup 36}S from {sup 36}Cl (t{sub 1/2} {approx} 0.3 Ma… more
Date: April 7, 2011
Creator: Wasserburg, G J; Hutcheon, I D; Aleon, J; Ramon, E C; Krot, A N; Nagashima, K et al.
Partner: UNT Libraries Government Documents Department
open access

Understanding Performance of Parallel Scientific Simulation Codes using Open|SpeedShop

Description: Conclusions of this presentation are: (1) Open SpeedShop's (OSS) is convenient to use for large, parallel, scientific simulation codes; (2) Large codes benefit from uninstrumented execution; (3) Many experiments can be run in a short time - might need multiple shots e.g. usertime for caller-callee, hwcsamp for HW counters; (4) Decent idea of code's performance is easily obtained; (5) Statistical sampling calls for decent number of samples; and (6) HWC data is very useful for micro-analysis but … more
Date: November 7, 2011
Creator: Ghosh, K K
Partner: UNT Libraries Government Documents Department
open access

CP Violation and Mixing in Charm Meson Decays from BaBar

Description: Mixing and CP violation in charm meson decays provide a unique probe of possible physics beyond the standard model. In this paper, we give a brief review of the current measurements from the BABAR experiment.
Date: February 7, 2011
Creator: Chen, Chunhui & U., /Iowa State
Partner: UNT Libraries Government Documents Department
open access

IMPACT OF THE SMALL COLUMN ION EXCHANGE PROCESS ON THE DEFENSE WASTE PROCESSING FACILITY - 12112

Description: The Savannah River Site (SRS) is investigating the deployment of a parallel technology to the Salt Waste Processing Facility (SWPF, presently under construction) to accelerate high activity salt waste processing. The proposed technology combines large waste tank strikes of monosodium titanate (MST) to sorb strontium and actinides with two ion exchange columns packed with crystalline silicotitanate (CST) resin to sorb cesium. The new process was designated Small Column Ion Exchange (SCIX), since… more
Date: November 7, 2011
Creator: Koopman, D.; Lambert, D.; Fox, K. & Stone, M.
Partner: UNT Libraries Government Documents Department
open access

Group velocity and pulse lengthening of mismatched laser pulses in plasma channels

Description: Analytic solutions are presented to the non-paraxial wave equation describing an ultra-short, low-power, laser pulse propagating in aplasma channel. Expressions for the laser pulse centroid motion and laser group velocity are derived, valid for matched and mismatchedpropagation in a parabolic plasma channel, as well as in vacuum, for an arbitrary Laguerre-Gaussian laser mode. The group velocity of amismatched laser pulse, for which the laser spot size is strongly oscillating, is found to be ind… more
Date: July 7, 2011
Creator: Schroeder, Carl; Benedetti, Carlo; Esarey, Eric; van Tilborg, Jeroen & Leemans, Wim
Partner: UNT Libraries Government Documents Department
open access

Measuring the Magnetic Center Behavior of an ILC Superconducting Quadrupole Prototype

Description: The main linacs of the proposed International Linear Collider (ILC) consist of superconducting cavities operated at 2K. The accelerating cavities are contained in a contiguous series of cryogenic modules that also house the main linac quadrupoles, thus the quadrupoles also need to be superconducting. In an early ILC design, these magnets are about 0.6 m long, have cos (2{theta}) coils, and operate at constant field gradients up to 60 T/m. In order to preserve the small beam emittances in the IL… more
Date: February 7, 2011
Creator: Spencer, Cherrill M.; Adolphsen, Chris; Berndt, Martin; Jensen, David R.; Rogers, Ron; Sheppard, John C. et al.
Partner: UNT Libraries Government Documents Department
open access

OPERATIONS REVIEW OF THE SAVANNAH RIVER SITE INTEGRATED SALT DISPOSITION PROCESS - 11327

Description: The Savannah River Site (SRS) is removing liquid radioactive waste from its Tank Farm. To treat waste streams that are low in Cs-137, Sr-90, and actinides, SRS developed the Actinide Removal Process and implemented the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU). The Actinide Removal Process contacts salt solution with monosodium titanate to sorb strontium and select actinides. After monosodium titanate contact, the resulting slurry is filtered to remove the monosodium titanate (a… more
Date: February 7, 2011
Creator: Peters, T.; Poirier, M.; Fondeur, F.; Fink, S.; Brown, S. & Geeting, M.
Partner: UNT Libraries Government Documents Department
open access

Measurements of the CKM angle gamma at BaBar

Description: We report on our recent measurements of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} and of related CP-asymmetries and branching fraction ratios. The measurements have been performed on samples of up to 465 million B{bar B} pairs collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B factory in the years 1999-2007.
Date: November 7, 2011
Creator: Marchiori, G.
Partner: UNT Libraries Government Documents Department
open access

Three years of Swift/BAT Survey of AGN: Reconciling Theory and Observations?

Description: It is well accepted that unabsorbed as well as absorbed AGN are needed to explain the nature and the shape of the Cosmic X-ray background, even if the fraction of highly absorbed objects (dubbed Compton-thick sources) substantially still escapes detection. We derive and analyze the absorption distribution using a complete sample of AGN detected by Swift-BAT in the first three years of the survey. The fraction of Compton-thick AGN represents only 4.6% of the total AGN population detected by Swif… more
Date: February 7, 2011
Creator: Burlon, D.; /Garching, Max Planck Inst., MPE; Ajello, M.; /SLAC /KIPAC, Menlo Park; Greiner, J.; /Garching, Max Planck Inst., MPE et al.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of Beam Loss and Energy Depositions for a Possible Phase II Design for LHC Collimation

Description: The LHC beams are designed to have high stability and to be stored for many hours. The nominal beam intensity lifetime is expected to be of the order of 20h. The Phase II collimation system has to be able to handle particle losses in stable physics conditions at 7 TeV in order to avoid beam aborts and to allow correction of parameters and restoration to nominal conditions. Monte Carlo simulations are needed in order to evaluate the behavior of metallic high-Z collimators during operation scenar… more
Date: November 7, 2011
Creator: Lari, L.; Assmann, R.; Bracco, C.; Brugger, M.; Cerutti, F.; Doyle, E. et al.
Partner: UNT Libraries Government Documents Department
open access

A Survey of Pressure Vessel Code Compliance for Super conducting RF Cryomodules

Description: Superconducting radio frequency (SRF) cavities made from niobium and cooled with liquid helium are becoming key components of many particle accelerators. The helium vessels surrounding the RF cavities, portions of the niobium cavities themselves, and also possibly the vacuum vessels containing these assemblies, generally fall under the scope of local and national pressure vessel codes. In the U.S., Department of Energy rules require national laboratories to follow national consensus pressure ve… more
Date: June 7, 2011
Creator: Peterson, Thomas; Klebaner, Arkadiy; Nicol, Tom; Theilacker, Jay; Hayano, Hitoshi; Kako, Eiji et al.
Partner: UNT Libraries Government Documents Department
open access

In-Flight Measurements of Capsule Adiabats in Laser Driven Spherical Implosions

Description: We present the first x-ray Thomson scattering measurements of temperature and density from spherically imploding matter. The shape of the Compton downscattered spectrum provides a first-principles measurement of the electron velocity distribution function, dependent on T{sub e} and the Fermi temperature T{sub F} {approx} n{sub e}{sup 2/3}. In flight compressions of Be and CH targets reach 6-13 times solid density, with T{sub e}/T{sub F} {approx} 0.4-0.7, resulting in minimum adiabats of {approx… more
Date: March 7, 2011
Creator: Kritcher, A L; Doppner, T; Fortman, C; Ma, T; Landen, O L; Wallace, R et al.
Partner: UNT Libraries Government Documents Department
open access

SC'11 Poster: A Highly Efficient MGPT Implementation for LAMMPS; with Strong Scaling

Description: The MGPT potential has been implemented as a drop in package to the general molecular dynamics code LAMMPS. We implement an improved communication scheme that shrinks the communication layer thickness, and increases the load balancing. This results in unprecedented strong scaling, and speedup continuing beyond 1/8 atom/core. In addition, we have optimized the small matrix linear algebra with generic blocking (for all processors) and specific SIMD intrinsics for vectorization on Intel, AMD, and … more
Date: December 7, 2011
Creator: Oppelstrup, T.; Stukowski, A. & Marian, J.
Partner: UNT Libraries Government Documents Department
open access

Optimization of Direct Ionization of CO2 by Controlling the Gas Flow Inside of a Beam-Target

Description: We designed and optimized a target that directs a CO{sub 2} pulse onto a Ti surface where a Cs{sup +} sputtering beam ionizes the CO{sub 2} to generate C{sup -}. These targets will be used for the direct ionization of CO{sub 2} pulses to enable the measurement of carbon isotope ratios in real time. The design was based on the results of Comsol{trademark} simulations of the target configurations.
Date: March 7, 2011
Creator: Salazar Quintero, G A & Ognibene, T
Partner: UNT Libraries Government Documents Department
open access

Advances in Parallel Electromagnetic Codes for Accelerator Science and Development

Description: Over a decade of concerted effort in code development for accelerator applications has resulted in a new set of electromagnetic codes which are based on higher-order finite elements for superior geometry fidelity and better solution accuracy. SLAC's ACE3P code suite is designed to harness the power of massively parallel computers to tackle large complex problems with the increased memory and solve them at greater speed. The US DOE supports the computational science R&D under the SciDAC proj… more
Date: February 7, 2011
Creator: Ko, Kwok; Candel, Arno; Ge, Lixin; Kabel, Andreas; Lee, Rich; Li, Zenghai et al.
Partner: UNT Libraries Government Documents Department
open access

Controls system developments for the ERL facility

Description: The BNL Energy Recovery LINAC (ERL) is a high beam current, superconducting RF electron accelerator that is being commissioned to serve as a research and development prototype for a RHIC facility upgrade for electron-ion collision (eRHIC). Key components of the machine include a laser, photocathode, and 5-cell superconducting RF cavity operating at a frequency of 703 MHz. Starting with a foundation based on existing ADO software running on Linux servers and on the VME/VxWorks platforms develope… more
Date: October 7, 2011
Creator: Jamilkowski, J.; Altinbas, Z.; Gassner, D.; Hoff, L.; Kankiya, P.; Kayran, D. et al.
Partner: UNT Libraries Government Documents Department
open access

GLASSES CONTAINING IRON (II III) OXIDES FOR IMMOBILIZATION OF RADIOACTIVE TECHNETIUM

Description: Technetium-99 (Tc-99) has posed serious environmental threats as US Department of Energy's high-level waste. This work reports the vitrification of Re, as surrogate for Tc-99, by iron-borosilicate and iron-phosphate glasses, respectively. Iron-phosphate glasses can dissolve Re as high as {approx} 1.2 wt. %, which can become candidate waste forms for Tc-99 disposal, while borosilicate glasses can retain less than 0.1 wt. % of Re due to high melting temperature and long melting duration. Vitrific… more
Date: November 7, 2011
Creator: AA, KRUGER; J, HEO; K, XU; JK, CHOI; PR, HRMA & W, UM
Partner: UNT Libraries Government Documents Department
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