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open access

2-D Path Corrections for Local and Regional Coda Waves: A Test of Transportability

Description: Reliable estimates of the seismic source spectrum are necessary for accurate magnitude, yield, and energy estimation. In particular, how seismic radiated energy scales with increasing earthquake size has been the focus of recent debate within the community and has direct implications on earthquake source physics studies as well as hazard mitigation. The 1-D coda methodology of Mayeda et al. [2003] has provided the lowest variance estimate of the source spectrum when compared against traditional… more
Date: July 13, 2005
Creator: Mayeda, K M; Malagnini, L; Phillips, W S; Walter, W R; Dreger, D S & Morasca, P
Partner: UNT Libraries Government Documents Department
open access

An 8-Element Fast-Neutron Double-Scatter Directional Detector.

Description: We have constructed a fast-neutron double-scatter spectrometer that efficiently measures the neutron spectrum and direction of a spontaneous fission source. The device consists of two planes of organic scintillators, each having an area of 125 cm{sup 2}, efficiently coupled to photomultipliers. The four scintillators in the front plane are 2 cm thick, giving almost 25% probability of detecting an incident fission-spectrum neutron at 2 MeV by proton recoil and subsequent ionization. The back pla… more
Date: July 31, 2005
Creator: Vanier, P. E. & Forman, L.
Partner: UNT Libraries Government Documents Department
open access

The 2mrad horizontal crossing angle IR layout for a TeV ILC

Description: The current status of the 2mrad crossing angle layout for the ILC is reviewed. The scheme developed in the UK and France is described and the performance discussed for a TeV machine. Secondly, the scheme developed at SLAC and BNL is then studied and modified for a TeV machine. We find that both schemes can handle the higher energy beam with modifications, and share many common features.
Date: July 27, 2005
Creator: Appleby, R.; Angal-Kalinin, D.; /Daresbury; Bambade, P.; Mouton, B.; /Orsay, LAL et al.
Partner: UNT Libraries Government Documents Department
open access

Absolute calibration of the Auger fluorescence detectors

Description: Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is st… more
Date: July 1, 2005
Creator: Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Advanced 0.3-NA EUV lithography capabilities at the ALS

Description: For volume nanoelectronics production using Extreme ultraviolet (EUV) lithography [1] to become a reality around the year 2011, advanced EUV research tools are required today. Microfield exposure tools have played a vital role in the early development of EUV lithography [2-4] concentrating on numerical apertures (NA) of 0.2 and smaller. Expected to enter production at the 32-nm node with NAs of 0.25, EUV can no longer rely on these early research tools to provide relevant learning. To overcome … more
Date: July 7, 2005
Creator: Naulleau, Patrick; Anderson, Erik; Dean, Kim; Denham, Paul; Goldberg, Kenneth A.; Hoef, Brian et al.
Partner: UNT Libraries Government Documents Department
open access

Advancements in time-resolved x-ray laser induced time-of-flight photoelectron spectroscopy

Description: Time-resolved soft x-ray photoelectron spectroscopy is used to probe the non-steady-state evolution of the valence band electronic structure of laser heated ultra-thin (50 nm) metal foils and bulk semiconductors. Single-shot soft x-ray laser induced time-of-flight photoelectron spectroscopy with picosecond time resolution was used in combination with optical measurements of the disassembly dynamics that have shown the existence of a metastable liquid phase in fs-laser heated metal foils persist… more
Date: July 28, 2005
Creator: Nelson, A J; Dunn, J; Widmann, K; Ao, T; Ping, Y; Hunter, J et al.
Partner: UNT Libraries Government Documents Department
open access

Advancing Usability Evaluation through Human Reliability Analysis

Description: This paper introduces a novel augmentation to the current heuristic usability evaluation methodology. The SPAR-H human reliability analysis method was developed for categorizing human performance in nuclear power plants. Despite the specialized use of SPAR-H for safety critical scenarios, the method also holds promise for use in commercial off-the-shelf software usability evaluations. The SPAR-H method shares task analysis underpinnings with human-computer interaction, and it can be easily adap… more
Date: July 1, 2005
Creator: Boring, Ronald L. & Gertman, David I.
Partner: UNT Libraries Government Documents Department
open access

Aerosol organic carbon to black carbon ratios: Analysis ofpublished data and implications for climate forcing

Description: Measurements of organic carbon (OC) and black carbon (BC)concentrations over a variety of locations worldwide, have been analyzed to infer the spatial distributions of the ratios of OC to BC. Since these ratios determine the relative amounts of scattering and absorption, they are often used to estimate the radiative forcing due to aerosols. An artifact in the protocol for filter measurements of OC has led to widespread overestimates of the ratio of OC to BC in atmospheric aerosols. We developed… more
Date: July 11, 2005
Creator: Novakov, T.; Menon, S.; Kirchstetter, T.W.; Koch, D. & Hansen, J.E.
Partner: UNT Libraries Government Documents Department
open access

The Affect of Realistic Geologic Heterogeneity on Local and Regional P/S Amplitude Ratios Based on Numerical Simulations

Description: Regional seismic discriminants based on high-frequency P/S ratios reliably distinguish between earthquakes and explosions. However, P/S discriminants in the 0.5 to 3 Hz band (where SNR can be highest) rarely perform well, with similar ratios for earthquake and explosion populations. Variability in discriminant performance has spawned numerous investigations into the generation of S-waves from explosions. Several viable mechanisms for the generation of S-waves from explosions have been forwarded… more
Date: July 11, 2005
Creator: Myers, S. C.; Wagoner, J. L.; Preston, L.; Smith, K. & Larsen, S. C.
Partner: UNT Libraries Government Documents Department
open access

Alternative Approach to Nuclear Data Representation

Description: This paper considers an approach for representing nuclear data that is qualitatively different from the approach currently adopted by the nuclear science community. Specifically, they examine a representation in which complicated data is described through collections of distinct and self contained simple data structures. This structure-based representation is compared with the ENDF and ENDL formats, which can be roughly characterized as dictionary-based representations. A pilot data representat… more
Date: July 27, 2005
Creator: Pruet, J.; Brown, D.; Beck, B. & McNabb, D. P.
Partner: UNT Libraries Government Documents Department
open access

An Amplitude Analysis of the Decay B+- -> pi+- pi+- pi-+

Description: The authors present a Dalitz-plot analysis of charmless B{sup {+-}} decays to the final state {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} using 210 fb{sup -1} of data recorded by the BABAR experiment at {radical}s = 10.58 GeV. We measure the branching fractions {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}}) = (16.2 {+-} 1.2 {+-} 0.9) x 10{sup -6} and {Beta}(B{sup {+-}} {yields} {rho}{sup 0}(770){pi}{sup {+-}}) = (8.8 {+-} 1.0 {+-} 0.6{sub -0.7}{sup +0.1}) x 10{sup -6}. M… more
Date: July 11, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Analysis of Artificial Radiocarbon in Different Skeletal and Dental Tissue Types to Evaluate Date of Death

Description: Radiocarbon dating, with special reference to the modern bomb-curve, can provide useful information to elucidate the date of death of skeletonized human remains. Interpretation can be enhanced with analysis of different types of tissues within a single skeleton because of the known variability of formation times and remodeling rates. Analysis of radiocarbon content of teeth, especially the enamel in tooth crowns provides information about the date of formation in the childhood years and in cons… more
Date: July 19, 2005
Creator: Ubelaker, D. H.; Buchholz, B. A. & Stewart, J.
Partner: UNT Libraries Government Documents Department
open access

Anisotropy studies around the Galactic Center at EeV energies with Auger data

Description: The Pierre Auger Observatory data have been analyzed to search for excesses of events near the direction of the galactic center in several energy ranges around EeV energies. In this region the statistics accumulated by the Observatory are already larger than that of any previous experiment. Using both the data sets from the surface detector and our hybrid data sets (events detected simultaneously by the surface detector and the fluorescence detector) we do not find any significant excess. At ou… more
Date: July 1, 2005
Creator: Letessier-Selvon, Antoine
Partner: UNT Libraries Government Documents Department
open access

ASM Conference on Prokaryotic Development

Description: Support was provided by DOE for the 2nd ASM Conference on Prokaryotic Development. The final conference program and abstracts book is attached. The conference presentations are organized around topics that are central to the current research areas in prokaryotic development. The program starts with topics that involve relatively simple models systems and ends with systems that are more complex. The topics are: i) the cell cycle, ii) the cytoskeleton, iii) morphogenesis, iv) developmental transc… more
Date: July 13, 2005
Creator: Kaplan, H. B.
Partner: UNT Libraries Government Documents Department
open access

Assessment of Seismic Analysis Methodologies for Deeply Embedded Npp Structures.

Description: Several of the new generation nuclear power plant designs have structural configurations which are proposed to be deeply embedded. Since current seismic analysis methodologies have been applied to shallow embedded structures (e.g., ASCE 4 suggest that simple formulations may be used to model embedment effect when the depth of embedment is less than 30% of its foundation radius), the US Nuclear Regulatory Commission is sponsoring a program at the Brookhaven National Laboratory with the objective… more
Date: July 1, 2005
Creator: Xu, J.; Miller, C.; Costantino, C.; Hofmayer, C. (Bnl) & Graves, H. (Us Nrc).
Partner: UNT Libraries Government Documents Department
open access

Atmospheric aerosol monitoring at the Pierre Auger Observatory

Description: For a ground based cosmic-ray observatory the atmosphere is an integral part of the detector. Air fluorescence detectors (FDs) are particularly sensitive to the presence of aerosols in the atmosphere. These aerosols, consisting mainly of clouds and dust, can strongly affect the propagation of fluorescence and Cherenkov light from cosmic-ray induced extensive air showers. The Pierre Auger Observatory has a comprehensive program to monitor the aerosols within the atmospheric volume of the detecto… more
Date: July 1, 2005
Creator: Cester, R.; Chiosso, M.; Chirin, J.; Clay, R.; Dawson, B.; Fick, B. et al.
Partner: UNT Libraries Government Documents Department
open access

Atmospheric profiles at the southern Pierre Auger Observatory and their relevance to air shower measurement

Description: The dependence of atmospheric conditions on altitude and time have to be known at the site of an air shower experiment for accurate reconstruction of extensive air showers and their simulations. The height-profile of atmospheric depth is of particular interest as it enters directly into the reconstruction of longitudinal shower development and of the primary energy and mass of cosmic rays. For the southern part of the Auger Observatory, the atmosphere has been investigated in a number of campai… more
Date: July 1, 2005
Creator: Keilhauer, B.; Bluemer, J.; Engel, R.; Gora, D.; Homola, P.; Klages, H. et al.
Partner: UNT Libraries Government Documents Department
open access

Atomistic mechanism of shock-induced void collapse in nano-porous metals

Description: We have investigated the microstructural changes in ductile porous metals during high pressure-high strain rate loading employing atomistic simulations and explored their relation to recent experiments on polycrystalline copper samples. Molecular-dynamics simulations of shocks in porous, single crystal samples show the formation of nano-grains due to localized massive plastic deformation induced by the presence of voids. In the process of grain formation the individual voids serve as dislocatio… more
Date: July 15, 2005
Creator: Erhart, P; Bringa, E; Kumar, M & Albe, K
Partner: UNT Libraries Government Documents Department
open access

Atomistic Modeling of Wave Propagation in Nanocrystals

Description: We present non-equilibrium molecular dynamics (MD) simulations of wave propagation in nanocrystals. We find that the width of the traveling wave front increases with grain size, d, as d{sup 1/2}. This width also decreases with the pressure behind the front. We extrapolate our results to micro-crystals and obtain reasonable agreement with experimental data. In addition, our extrapolation agrees with models that only take into account the various velocities of propagation along different crystall… more
Date: July 5, 2005
Creator: Bringa, E; Caro, A; Victoria, M & Park, N
Partner: UNT Libraries Government Documents Department
open access

Automated Microwave Low Power Testing Techniques for NLC

Description: As part of the Next Linear Collider (NLC) collaboration, the NLC structures group at Fermilab has started an R&D program to fabricate NLC accelerator structures in cooperation with commercial companies in order to prepare for mass production of RF structures. To build the Next Linear Collider, thousands accelerator structures containing a million cells are needed. Our primary goal is to explore the feasibility of making these structures in an industrial environment. On the other hand the st… more
Date: July 8, 2005
Creator: Carter, H.; Finley, D.; Gonin, I.; Khabibullin, T.; Romanov, G.; Sun, D. et al.
Partner: UNT Libraries Government Documents Department
open access

B tagging at CDF

Description: The authors describe the algorithms used to identify b jets in CDF, and discuss various methods used to measure their performance.
Date: July 1, 2005
Creator: Jeans, Daniel & /INFN, CNAF /INFN, Rome
Partner: UNT Libraries Government Documents Department
open access

b-tagging at D0

Description: Many high p{sub T} physics analyses at the Tevatron contain a b-quark and hence a b-jet in the final states. We report on the b-jet identification methods in D0 and their performance. For 0.5% of light jet tagging rate, 40 or 45% of b-jet tagging efficiency is achieved for jets with 35 < E{sub T} < 55 GeV and |{eta}| < 1.2.
Date: July 1, 2005
Creator: Hanagaki, K.
Partner: UNT Libraries Government Documents Department
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