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Optical analogs of model atoms in fields

Description: The equivalence of the paraxial wave equation to a time-dependent Schroedinger equation is exploited to construct optical analogs of model atoms in monochromatic fields. The approximation of geometrical optics provides the analog of the corresponding classical mechanics. Optical analogs of Rabi oscillations, photoionization, stabilization, and the Kramers-Henneberger transformation are discussed. One possibility for experimental realization of such optical analogs is proposed. These analogs may… more
Date: May 2, 1991
Creator: Milonni, P.W.
Partner: UNT Libraries Government Documents Department
open access

LSI/CAMAC system for heavy elements research

Description: We have developed a LSI-11/23 computer-driven CAMAC data acquisition system. The 64 silicon-detector system is being used to investigate the alpha and spontaneous fission activities of short-lived transfermium isotopes by the real-time monitoring of the mother-daughter alpha decay sequence. A unique modular pulse processing electronics system was designed to simplify set up and calibration. The computer adjusts the gain of the CAMAC shaping amplifiers enabling the calibration and alignment of a… more
Date: May 2, 1985
Creator: Watkins, E. D.; Dougan, R. J. & McQuaid, J. H.
Partner: UNT Libraries Government Documents Department
open access

Galvanic interpretation of self-potential signals associated withmicrobial sulfate-reduction

Description: We have evaluated the usefulness of the self-potential (SP)geophysical method to track the onset and location of microbialsulfate-reduction in saturated sediments during organic carbon amendment.Following stimulation of sulfate-reducing bacteria (SRB) by addition oflactate, anomalous voltages exceeding 600 mV correlated in space and timewith the accumulation of dissolved sulfide. Abiotic experiments in whichthe sulfide concentration at the measurement electrode was systematicallyvaried showed a… more
Date: May 2, 2007
Creator: Williams, Kenneth H.; Hubbard, Susan S. & Banfield, Jillian F.
Partner: UNT Libraries Government Documents Department
open access

Effect of rogue particles on the sub-surface damage of fused silica during grinding/polishing

Description: The distribution and characteristics of surface cracks (i.e., sub-surface damage or scratching) on fused silica formed during grinding/polishing resulting from the addition of rogue particles in the base slurry has been investigated. Fused silica samples (10 cm diameter x 1 cm thick) were: (1) ground by loose abrasive grinding (alumina particles 9-30 {micro}m) on a glass lap with the addition of larger alumina particles at various concentrations with mean sizes ranging from 15-30 {micro}m, or (… more
Date: May 2, 2007
Creator: Suratwala, T I; Steele, R; Feit, M D; Wong, L; Miller, P E; Menapace, J A et al.
Partner: UNT Libraries Government Documents Department
open access

Ovarian carcinomas with genetic and epigenetic BRCA1 loss have distinct molecular abnormalities

Description: Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas. A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRC… more
Date: May 2, 2008
Creator: Gilks, C. Blake; Press, Joshua Z.; De Luca, Alessandro; Boyd, Niki; Young, Sean; Troussard, Armelle et al.
Partner: UNT Libraries Government Documents Department
open access

Electron-Heated Target Temperature Measurements in Petawatt Laser Experiments Based on Extreme Ultraviolet Imaging and Spectroscopy

Description: Three independent methods (XUV spectroscopy, imaging at 68 eV and 256 eV) have been used to measure planar target rear surface plasma temperature due to heating by hot electrons. The hot electrons are produced by ultra-intense laser plasma interactions using the 150 J, 0.5 ps Titan laser. Soft x-ray spectroscopy in the 50-400 eV region and imaging at the 68 eV and 256 eV photon energies were used to determine the rear surface temperature of planar CD targets. Temperatures were found to be in th… more
Date: May 2, 2008
Creator: Ma, T. A.; Beg, F. N.; Macphee, A. G.; Chung, H. K.; Key, M. H.; Mackinnon, A. J. et al.
Partner: UNT Libraries Government Documents Department
open access

A Bremsstrahlung Spectrometer using k-edge and Differential Filters with Image plate dosimeters

Description: A Bremsstrahlung spectrometer using k-edge and differential filtering has been used with Image Plate dosimeters to measure the x-ray fluence from short-pulse laser/target interactions. An electron spectrometer in front of the Bremsstrahlung spectrometer deflects electrons from the x-ray line of sight and simultaneously measures the electron spectrum. The response functions were modeled with the Monte Carlo code Integrated Tiger Series 3.0 and the dosimeters calibrated with radioactive sources. … more
Date: May 2, 2008
Creator: Chen, C.; Mackinnon, A.; Beg, F.; Chen, H.; Key, M.; King, J. A. et al.
Partner: UNT Libraries Government Documents Department
open access

High Bandwidth Data Recording Systems for Pulsed Power and Laser Produced Plasma Experiments.

Description: We present two high bandwidth data transmission and recording systems for the measurement of transient signals during pulsed power and laser produced plasmas. These systems use fiber optic cables to transmit analog data over long distances to high bandwidth digitizing oscilloscopes. One system is based on the direct modulation of a laser diode and has a bandwidth of 1.5 GHz. The other system is based upon a fiber-optic Mach-Zehnder modulator and has a bandwidth of 12 GHz, and is limited by the … more
Date: May 2, 2006
Creator: May, M. J.; Clancy, T.; Fittinghoff, D.; Halvorson, C.; MIlls, T.; Nikitin, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Influence of radiation damage and isochronal annealing on the magnetic susceptibility of Pu(1-x)Am(x) alloys

Description: Results of radiation damage in Pu and Pu{sub 1-x}Am{sub x} alloys studied with magnetic susceptibility, {chi}(T), and resistivity are presented. Damage accumulated at low temperatures increases {chi}(T) for all measured alloys, with the trend generally enhanced as the lattice expands. There is a trend towards saturation observable in the damage induced magnetic susceptibility data, that is not evident in similar damage induced resistivity data taken on the same specimen. A comparison of isochro… more
Date: May 2, 2008
Creator: McCall, S; Fluss, M; Chung, B & Haire, R
Partner: UNT Libraries Government Documents Department
open access

Fabry-Perot / PDV Comparison

Description: Measures the fast pulses seen with exploding bridge flyers by PDV
Date: May 2, 2007
Creator: Hodgin, Ralph; May, Chadd; Hanks, Roy; Hansen, Don; Whitworth, Tony & Strand, Ted
Partner: UNT Libraries Government Documents Department
open access

Overview of equilibrium reconstruction on DIII-D using new measurements from an expanded motional Stark effect diagnostic

Description: Motional Stark effect (MSE) measurements constrain equilibrium reconstruction of DIII-D tokamak plasmas using the equilibrium code EFIT. In 2007, two new MSE arrays were brought online, bringing the system to three core arrays, two edge arrays, and 64 total channels. We present the first EFIT reconstructions using this expanded system. Safety factor and E{sub R} profiles produced by fitting to data from the two new arrays and one of the other three agree well with independent measurements. Comp… more
Date: May 2, 2008
Creator: Holcomb, C; Makowski, M; Allen, S; Meyer, W & Van Zeeland, M
Partner: UNT Libraries Government Documents Department
open access

How to Find More Supernovae with Less Work: Object ClassificationTechniques for Difference Imaging

Description: We present the results of applying new object classificationtechniques to difference images in the context of the Nearby SupernovaFactory supernova search. Most current supernova searches subtractreference images from new images, identify objects in these differenceimages, and apply simple threshold cuts on parameters such as statisticalsignificance, shape, and motionto reject objects such as cosmic rays,asteroids, and subtraction artifacts. Although most static objectssubtract cleanly, even a … more
Date: May 2, 2007
Creator: Bailey, Stephen; Aragon, Cecilia; Romano, Raquel; Thomas, RollinC.; Weaver, Benjamin A. & Wong, Daniel
Partner: UNT Libraries Government Documents Department
open access

Angular Distributions in the Decays B to K*l+l-

Description: The authors use a sample of 384 million B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider to study angular distributions in the rare decays B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -}. For low dilepton invariant masses, m{sub {ell}{ell}} < 2.5 GeV/c{sup 2}, they measure a lepton forward-backward asymmetry {Alpha}{sub FB} = 0.24{sub -0.23}{sup +0.18} {+-} 0.05 and K* longitud… more
Date: May 2, 2008
Creator: Collaboration, The BABAR & Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Towards consistent chronology in the early Solar System: high resolution 53Mn-53Cr chronometry for chondrules.

Description: New high-precision {sup 53}Mn-{sup 53}Cr data obtained for chondrules extracted from a primitive ordinary chondrite, Chainpur (LL3.4), define an initial {sup 53}Mn/{sup 55}Mn ratio of (5.1 {+-} 1.6) x 10{sup -6}. As a result of this downward revision from an earlier higher value of (9.4 {+-} 1.7) x 10{sup -6} for the same meteorite (Nyquist et al. 2001), together with an assessment of recent literature, we show that a consistent chronology with other chronometers such as the {sup 26}Al-{sup 26}… more
Date: May 2, 2007
Creator: Yin, Q; Jacobsen, B; Moynier, F & Hutcheon, I D
Partner: UNT Libraries Government Documents Department
open access

A Hard X-ray View on Two Distant VHE Blazars: 1ES 1101-232 and 1ES 1553+113

Description: TeV-blazars are known as prominent non-thermal emitters across the entire electromagnetic spectrum with their photon power peaking in the X-ray and TeV-band. If distant, absorption of -ray photons by the extragalactic background light (EBL) alters the intrinsic TeV spectral shape, thereby affecting the overall interpretation. Suzaku observations for two of the more distant TeV-blazars known to date, 1ES 1101-232 and 1ES 1553+113, were carried out in May and July 2006, respectively, including a … more
Date: May 2, 2008
Creator: Reimer, A.; Costamente, L.; /Stanford U., HEPL /KIPAC, Menlo Park; Madejski, G.; /KIPAC, Menlo Park /SLAC; Reimer, O. et al.
Partner: UNT Libraries Government Documents Department
open access

FOAM DENSITY SENSITIVITY STUDY FOR THE 9977 PACKAGE

Description: Two layers of insulation fill the volume of the 9977 package between the drum liner and the shell. One of these layers is composed of General Plastics FR-3716 polyurethane foam (also known as Last-A-Foam{reg_sign}), poured through fill holes in the drum bottom and foamed in place. There was concern that the density of the foam insulating layer may vary due to the manufacturing process and that variations in foam density would compromise the safety basis of the package. Thus, a structural finite… more
Date: May 2, 2008
Creator: Gorczyca, J & Tsu-Te Wu, T
Partner: UNT Libraries Government Documents Department
open access

Babel Fortran 2003 Binding for Structured Data Types

Description: Babel is a tool aimed at the high-performance computing community that addresses the need for mixing programming languages (Java, Python, C, C++, Fortran 90, FORTRAN 77) in order to leverage the specific benefits of those languages. Scientific codes often rely on structured data types (structs, derived data types) to encapsulate data, and Babel has been lacking in this type of support until recently. We present a new language binding that focuses on their interoperability of C/C++ with Fortran … more
Date: May 2, 2008
Creator: Muszala, S; Epperly, T & Wang, N
Partner: UNT Libraries Government Documents Department
open access

Dirty Bomb Fallout

Description: At present, there is a significant need to develop decontamination agents that can be used effectively after detonation of a radiological dispersal device (RDD) in an urban environment. There is also a need for the development of reproducible test surfaces to be used to determine the efficacy of the agent being developed. Researchers at Lawrence Livermore National Laboratory (LLNL), under the auspices of the US Department of Energy (DoE), conducted a field study to evaluate the deposition of an… more
Date: May 2, 2007
Creator: Gates-Anderson, D.; Rasmussen, C.; Fischer, R.; Viani, B.; Hu, Q.; Sutton, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Dark Matter Capture and Annihilation on the First Stars: Preliminary Estimates

Description: Assuming that Dark Matter is dominated by WIMPs, it accretes by gravitational attraction and scattering over baryonic material and annihilates inside celestial objects, giving rise to a 'Dark Luminosity' which may potentially affect the evolution of stars. We estimate the Dark Luminosity achieved by different kinds of stars in a halo with DM properties characteristic of the ones where the first star formation episode occurs. We find that either massive, metal-free and small, galactic-like stars… more
Date: May 2, 2008
Creator: Iocco, Fabio
Partner: UNT Libraries Government Documents Department
open access

Assessment of fire hazards in buildings housing fusion energy experiments

Description: A number of materials in and within the proximity of buildings housing fusion energy experiments (FEE) were analyzed for their potential fire hazard. The materials used in this study were mostly: electrical and thermal insulations. The fire hazard of these materials was assessed in terms of their ease of ignition, heat release rate, generation of smoke, and the effect of thermal environment on the combustion behavior. Several fire protection measures for buildings housing the (FEE) projects are… more
Date: May 2, 1978
Creator: Alvares, N. & Lipska, A.
Partner: UNT Libraries Government Documents Department
open access

Decentralized energy planning and consensus in energy policy

Description: This paper explores the following three propositions and their relationships: (1) that, in our pluralistic policymaking environment, we cannot solve our nation's energy problems unless we can reach agreement among a diverse group of interested parties about specific actions; (2) that, short of a manifest emergency, such a consensus is difficult to reach unless the scale of the decision-making unit is relatively small; and therefore (3) that one of the keys to an effective energy policy in the U… more
Date: May 2, 1980
Creator: Wilbanks, T.J.
Partner: UNT Libraries Government Documents Department
open access

Characterization of transuranium actinide alloy phase diagrams

Description: Alloys of Np have been studied less than those,of the neighboring elements, U and Pu; the higher actinides have received even less attention. Recent interest in {sup 237}Np, {sup 241}Am and other actinide isotopes as significant, long-lived and highly radiotoxic nuclear waste components, and particularly the roles of metallic materials new handling/separations and remediation technologies, demands that this paucity of information concerning alloy behaviors be addressed. An additional interest i… more
Date: May 2, 1994
Creator: Gibson, J. K.; Haire, R. G.; Gensini, M. M. & Ogawa, T.
Partner: UNT Libraries Government Documents Department
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