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2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012

Description: Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.
Date: August 24, 2012
Creator: Kelemen, Peter
Partner: UNT Libraries Government Documents Department
open access

PEP-II Status and Outlook

Description: PEP-II/BABAR are presently in their second physics run. With machine and detector performance and reliability at an all-time high, almost 51 fb{sup -1} have been integrated by BABAR up to mid-October 2001. PEP-II luminosity has reached 4.4 x 10{sup 33} cm{sup -2} s{sup -1} and our highest monthly delivered luminosity has been above 6 pb{sup -1}, exceeding the performance parameters given in the PEP-II CDR by almost 50%. The increase compared to the first run in 2000 has been achieved by a combi… more
Date: April 24, 2012
Creator: Wienands, H. U.; Biagini, M. E.; Decker, F. J.; Donald, M. H.; Ecklund, S.; Fisher, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Electron Beam Polarization Measurement Using Touschek Lifetime Technique

Description: Electron beam loss due to intra-beam scattering, the Touschek effect, in a storage ring depends on the electron beam polarization. The polarization of an electron beam can be determined from the difference in the Touschek lifetime compared with an unpolarized beam. In this paper, we report on a systematic experimental procedure recently developed at Duke FEL laboratory to study the radiative polarization of a stored electron beam. Using this technique, we have successfully observed the radiativ… more
Date: August 24, 2012
Creator: Sun, Changchun; Li, Jingyi; Mikhailov, Stepan; Popov, Victor; Wu, Wenzhong; Wu, Ying et al.
Partner: UNT Libraries Government Documents Department
open access

High Multiplicity Searches at the LHC Using Jet Masses

Description: This article introduces a new class of searches for physics beyond the Standard Model that improves the sensitivity to signals with high jet multiplicity. The proposed searches gain access to high multiplicity signals by reclustering events into large-radius, or 'fat', jets and by requiring that each event has multiple massive jets. This technique is applied to supersymmetric scenarios in which gluinos are pair-produced and then subsequently decay to final states with either moderate quantities… more
Date: April 24, 2012
Creator: Hook, Anson; /SLAC /Stanford U., Appl. Phys. Dept.; Izaguirre, Eder; /SLAC /Stanford U., Phys. Dept.; Lisanti, Mariangela; U., /Princeton et al.
Partner: UNT Libraries Government Documents Department
open access

A METHODOLOGY FOR DETERMINING THE DOSE RATE FOR BOUNDING MASS LIMITS IN A 9977 PACKAGING

Description: The Small Gram Quantity (SGQ) concept is based on the understanding that the hazards associated with the shipment of a radioactive material are directly proportional to its mass. This study describes a methodology that estimates the acceptable masses for several neutron and gamma emitting isotopes that can be shipped in a 9977 Package compliant with the Title 10 of the Code of Federal Regulations, Part 71 (10CFR71) external radiation level limits. 10CFR71.33 states that a shipping application i… more
Date: May 24, 2012
Creator: Abramczyk, G.; Bellamy, S.; Nathan, S. & Loftin, B.
Partner: UNT Libraries Government Documents Department
open access

LSST Camera Optics Design

Description: The Large Synoptic Survey Telescope (LSST) uses a novel, three-mirror, telescope design feeding a camera system that includes a set of broad-band filters and three refractive corrector lenses to produce a flat field at the focal plane with a wide field of view. Optical design of the camera lenses and filters is integrated in with the optical design of telescope mirrors to optimize performance. We discuss the rationale for the LSST camera optics design, describe the methodology for fabricating, … more
Date: May 24, 2012
Creator: Riot, V. J.; Olivier, S.; Bauman, B.; Pratuch, S.; Seppala, L.; Gilmore, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Rapid Determination Of Radiostrontium In Large Soil Samples

Description: A new method for the determination of radiostrontium in large soil samples has been developed at the Savannah River Environmental Laboratory (Aiken, SC, USA) that allows rapid preconcentration and separation of strontium in large soil samples for the measurement of strontium isotopes by gas flow proportional counting. The need for rapid analyses in the event of a Radiological Dispersive Device (RDD) or Improvised Nuclear Device (IND) event is well-known. In addition, the recent accident at Fuku… more
Date: May 24, 2012
Creator: Maxwell, Sherrod L.; Culligan, Brian K. & Shaw, Patrick J.
Partner: UNT Libraries Government Documents Department
open access

Coupling Impedance of a Periodic Array of Diaphragms (Erratum)

Description: A method is presented for calculating the high-frequency longitudinal and transverse coupling impedances in a periodic array of diaphragms in a circular perfectly conducting pipe. The method is based on Weinstein's theory of diffraction of a plane electromagnetic wave on a stack of halfplanes. Using Weinstein's solution, it is shown that the problem of finding the beam field in the pipe reduces to an effective boundary condition at the radius of the diaphragms that couples the longitudinal elec… more
Date: May 24, 2012
Creator: Stupakov, G. V.
Partner: UNT Libraries Government Documents Department
open access

Photonic Doppler Velocimetry Multiplexing Techniques: Evaluation of Photonic Techniques

Description: This poster reports progress related to photonic technologies. Specifically, the authors developed diagnostic system architecture for a Multiplexed Photonic Doppler Velocimetry (MPDV) that incorporates frequency and time-division multiplexing into existing PDV methodology to provide increased channel count. Current MPDV design increases number of data records per digitizer channel 8x, and also operates as a laser-safe (Class 3a) system. Further, they applied heterodyne interferometry to allow f… more
Date: May 24, 2012
Creator: Daykin, Edward
Partner: UNT Libraries Government Documents Department
open access

Femtosecond Synchronization of Laser Systems for the LCLS

Description: The scientific potential of femtosecond x-ray pulses at linac-driven free-electron lasers such as the Linac Coherent Light Source is tremendous. Time-resolved pump-probe experiments require a measure of the relative arrival time of each x-ray pulse with respect to the experimental pump laser. An optical timing system based on stabilized fiber links has been developed for the LCLS to provide this synchronization. Preliminary results show synchronization of the installed stabilized links at the s… more
Date: August 24, 2012
Creator: Byrd, John; Doolittle, Lawrence; Huang, Gang; Staples, John; Wilcox, Russell; Arthur, John et al.
Partner: UNT Libraries Government Documents Department
open access

Geochemical and Strontium Isotope Characterization of Produced Waters from Marcellus Shale Natural Gas Extraction

Description: Extraction of natural gas by hydraulic fracturing of the Middle Devonian Marcellus Shale, a major gas-bearing unit in the Appalachian Basin, results in significant quantities of produced water containing high total dissolved solids (TDS). We carried out a strontium (Sr) isotope investigation to determine the utility of Sr isotopes in identifying and quantifying the interaction of Marcellus Formation produced waters with other waters in the Appalachian Basin in the event of an accidental release… more
Date: February 24, 2012
Creator: Chapman, Elizabeth C.; Capo, Rosemary. C.; Stewart, Brian W.; Kirby, Carl S.; Hammack, Richard W.; Schroeder, Karl T. et al.
Partner: UNT Libraries Government Documents Department
open access

Determination of the 242Pu Branching Ratio via Alpha-Gamma Coincidence

Description: When the burn-up is high, the {sup 242}Pu isotopic content becomes more important. The traditional correlation method will fail. The {sup 242}Pu isotopic content in the sample plays an essential role if the neutron coincidence method is used to quantify the total amount of plutonium. In one of the earlier measurements we had a chance to measure an isotopic pure (> 99.95 %) {sup 242}Pu thick sample and realized that the difference in the branching ratio (BR) value among current nuclear data3)… more
Date: May 24, 2012
Creator: Wang, T. F.
Partner: UNT Libraries Government Documents Department
open access

ENHANCED SAFEGUARDS: THE ROLE OF SMART FUNCTIONAL COATINGS FOR TAMPER INDICATION

Description: This work investigates the synthesis of smart functional coatings (SFC) using chemical solution deposition methods. Chemical solution deposition methods have recently received attention in the materials research community due to several unique advantages that include low temperature processing, high homogeneity of final products, the ability to fabricate materials with controlled surface properties and pore structures, and the ease of dopant incorporation in controlled concentrations. The optic… more
Date: February 24, 2012
Creator: Mendez-Torres, A.; Martinez-Rodriguez, M.; Brinkman, K. & Krementz, D.
Partner: UNT Libraries Government Documents Department
open access

No-Core Shell Model Analysis Of Light Nuclei

Description: No Description Available.
Date: September 24, 2012
Creator: Quaglioni, S; Navratil, P; Hupin, G; Langhammee, J; Romero-Redondo, C & Roth, R
Partner: UNT Libraries Government Documents Department
open access

The First Angstrom X-Ray Free-Electron Laser

Description: The Linac Coherent Light Source produced its first x-ray laser beam on 10 April 2009. Today it is routinely producing x-ray pulses with energy >2 mJ across the operating range from 820-8,200 eV. The facility has begun operating for atomic/molecular/optical science experiments. Performance of the facility in its first user run (1 October - 21 December) and current machine development activities will be presented. Early results from the preparations for the start of the second user run is also… more
Date: August 24, 2012
Creator: Galayda, John
Partner: UNT Libraries Government Documents Department
open access

Prompt Neutron Lifetime for the NBSR Reactor

Description: In preparation for the proposed conversion of the National Institute of Standards and Technology (NIST) research reactor (NBSR) from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel, certain point kinetics parameters must be calculated. We report here values of the prompt neutron lifetime that have been calculated using three independent methods. All three sets of calculations demonstrate that the prompt neutron lifetime is shorter for the LEU fuel when compared to the HEU fuel an… more
Date: June 24, 2012
Creator: Hanson, A. L. & Diamond, D.
Partner: UNT Libraries Government Documents Department
open access

Linear response at criticality

Description: In this article, the authors study a set of cooperatively interacting units at criticality, and prove with analytical and numerical arguments that they generate the same renewal non-Poisson intermittency as that produced by blinking quantum dots.
Date: October 24, 2012
Creator: Svenkeson, Adam; Bologna, Mauro & Grigolini, Paolo
Partner: UNT College of Arts and Sciences
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