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Schemes for anti pp interactions at ISABELLE

Description: Various schemes for obtaining anti pp interactions are outlined, and the luminosities obtainable for each case calculated. In the simplest realistic case, a luminosity of 1.3 x 10/sup 29/ is obtained with a 13 hour filling time. The addition of special rf systems in both the AGS and ISABELLE give a scheme with luminosity 8 x 10/sup 29/ in 6 hours. The use of stochastic cooling to stack raises the luminosity to as high as 10/sup 31/ but the filling time is then 68 hours. Finally a scheme is cons… more
Date: September 8, 1977
Creator: Palmer, Robert B.
Partner: UNT Libraries Government Documents Department
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Field investigation of the drift shadow

Description: A drift shadow is an area immediately beneath an undergroundvoidthat, in theory, will be relatively drier than the surrounding rockmass. Numerical and analytical models of water flow through unsaturatedrock predict the existence of a drift shadow, but field tests confirmingits existence have yet to be performed. Proving the existence of driftshadows and understanding their hydrologic and transport characteristicscould provide a better understanding of how contaminants move in thesubsurface if r… more
Date: September 8, 2005
Creator: Su, Grace W.; Kneafsey, Timothy J.; Ghezzehei, Teamrat A.; Marshall, Brian D. & Cook, Paul J.
Partner: UNT Libraries Government Documents Department
open access

A QR accelerated volume-to-surface boundary condition for finite element solution of eddy current problems

Description: We are concerned with the solution of time-dependent electromagnetic eddy current problems using a finite element formulation on three-dimensional unstructured meshes. We allow for multiple conducting regions, and our goal is to develop an efficient computational method that does not require a computational mesh of the air/vacuum regions. This requires a sophisticated global boundary condition specifying the total fields on the conductor boundaries. We propose a Biot-Savart law based volume-to-… more
Date: September 8, 2006
Creator: White, D; Fasenfest, B; Rieben, R & Stowell, M
Partner: UNT Libraries Government Documents Department
open access

Density changes in Ga-stabilized delta-Pu, and what they mean

Description: Ga-stabilized {delta}-Pu undergoes small changes in density with time. These have been associated with four different causes: an initial reversible expansion that saturates after a short time; a continuous change that can be attributed to the in-growth of helium and actinide daughter products from the radioactive decay of plutonium; possible void swelling; and phase instability. We review our present understanding of these processes and evaluate their contributions to density changes. It is sho… more
Date: September 8, 2006
Creator: G.Wolfer, W.; Kubota, A.; S?derlind, P.; Landa, A.; Oudot, B.; Sadigh, B. et al.
Partner: UNT Libraries Government Documents Department
open access

Comments on Shimony's 'An Analysis of Stapp's 'A bell-type theoremwithout hidden variables''

Description: The hidden-variable theorems of Bell and followers depend upon an assumption, namely the hidden-variable assumption, that conflicts with the precepts of quantum philosophy. Hence from an orthodox quantum perspective those theorems entail no faster-than-light transfer of information. They merely reinforce the ban on hidden variables. The need for some sort of faster-than-light information transfer can be shown by using counterfactuals instead of hidden variables. Shimony's criticism of that argu… more
Date: September 8, 2004
Creator: Stapp, Henry P.
Partner: UNT Libraries Government Documents Department
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Z-Beamlet (ZBL) Multi-Frame Back-lighter (MFB) System for ICF/Plasma Diagnostics

Description: Z-Beamlet [1] is a single-beam high-energy Nd:glass laser used for backlighting high energy density (HED) plasma physics experiments at Sandia's Z-accelerator facility. The system currently generates a single backlit image per experiment, and has been employed on approximately 50% of Z-accelerator system shots in recent years. We have designed and are currently building a system that uses Z-Beamlet to generate two distinct backlit images with adjustable time delay ranging from 2 to 20 ns betwee… more
Date: September 8, 2005
Creator: Caird, J A; Erlandson, A C; Molander, W A; Murray, J E; Robertson, G K; Smith, I C et al.
Partner: UNT Libraries Government Documents Department
open access

Five New High-Redshift Quasar Lenses from the Sloan Digital Sky Survey

Description: We report the discovery of five gravitationally lensed quasars from the Sloan Digital Sky Survey (SDSS). All five systems are selected as two-image lensed quasar candidates from a sample of high-redshift (z > 2.2) SDSS quasars. We confirmed their lensing nature with additional imaging and spectroscopic observations. The new systems are SDSS J0819+5356 (source redshift z{sub s} = 2.237, lens redshift z{sub l} = 0.294, and image separation {theta} = 4.04 inch), SDSS J1254+2235 (z{sub s} = 3.62… more
Date: September 8, 2008
Creator: Inada, Naohisa; Oguri, Masamune; Shin, Min-Su; Kayo, Issha; Strauss, Michael A.; Morokuma, Tomoki et al.
Partner: UNT Libraries Government Documents Department
open access

Discovery of an Unusual Optical Transient with the Hubble Space Telescope

Description: We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The transient brightened over a period of ~;;100 days, reached a peak magnitude of ~;;21.0 in both i_775 and z_850, and then declined over a similar timescale. There is no host galaxy or progenitor star detected at the location of the transient to a 3 sigma upper limit of i_775 = 26.4 and z_850 = 26.1, giving a corresponding lower limit on the flux increase of… more
Date: September 8, 2008
Creator: Project, The Supernova Cosmology; Barbary, Kyle; Dawson, Kyle S.; Tokita, Kouichi; Aldering, Greg; Amanullah, Rahman et al.
Partner: UNT Libraries Government Documents Department
open access

Substrate-induced band gap opening in epitaxial graphene

Description: Graphene has shown great application potential as the hostmaterial for next-generation electronic devices. However, despite itsintriguing properties, one of the biggest hurdles for graphene to beuseful as an electronic material is the lack of an energy gap in itselectronic spectra. This, for example, prevents the use of graphene inmaking transistors. Although several proposals have been made to open agap in graphene's electronic spectra, they all require complexengineering of the graphene layer… more
Date: September 8, 2007
Creator: Zhou, S. Y.; Gweon, G.-H.; Fedorov, A. V.; First, P. N.; de Heer, W. A.; Lee, D.-H. et al.
Partner: UNT Libraries Government Documents Department
open access

BlueGene/L Applications: Parallelism on a Massive Scale

Description: BlueGene/L (BG/L), developed through a partnership between IBM and Lawrence Livermore National Laboratory (LLNL), is currently the world's largest system both in terms of scale with 131,072 processors and absolute performance with a peak rate of 367 TFlop/s. BG/L has led the Top500 list the last four times with a Linpack rate of 280.6 TFlop/s for the full machine installed at LLNL and is expected to remain the fastest computer in the next few editions. However, the real value of a machine like … more
Date: September 8, 2006
Creator: de Supinski, B. R.; Schulz, M.; Bulatov, V. V.; Cabot, W.; Chan, B.; Cook, A. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Bendable X-ray Optics at the ALS: Design, Tuning, Performance and Applications

Description: We review the development at the Advanced Light Source (ALS) of bendable x-ray optics widely used for focusing of beams of soft and hard x-rays. Typically, the focusing is divided in the tangential and sagittal directions into two elliptically cylindrical reflecting elements, the so-called Kirkpatrick-Baez (KB) pair [1]. Because fabrication of elliptical surfaces is complicated, the cost of directly fabricated tangential elliptical cylinders is often prohibitive. This is in contrast to flat opt… more
Date: September 8, 2008
Creator: Advanced Light Source, Lawrence Berkeley National Laboratory; Yashchuk, Valeriy V.; Church, Matthew N.; Knight, Jason W.; Kunz, Martin; MacDowell, Alastair A. et al.
Partner: UNT Libraries Government Documents Department
open access

Automatic gas-levitation system for vacuum deposition of laser-fusion targets

Description: An improved simple system has been developed to gas-levitate microspheres during vacuum-deposition processes. The automatic operation relies on two effects: a lateral stabilizing force provided by a centering-ring; and an automatically incremented gas metering system to offset weight increases during coating.
Date: September 8, 1981
Creator: Jordan, C. W.; Cameron, G. R.; Krenik, R. M. & Crane, J. K.
Partner: UNT Libraries Government Documents Department
open access

Energy balance in laser-irradiated vaporizing droplets

Description: We analyze the interactions of atmospheric aerosols with a high-energy laser beam. The energy balance equation allows us to compute the conversion of the pulse energy into temperature increase, vaporization, conduction, and convection. We also include the shrinkage term whose significance has recently been discussed by Davies and Brock.
Date: September 8, 1987
Creator: Zardecki, A. & Armstrong, R.L.
Partner: UNT Libraries Government Documents Department
open access

XUV emission features from the Livermore soft x-ray laser experiments

Description: The measured wavelengths in the soft x-ray region for 3p to 3s and 3d to 3p transitions in neon-, sodium-, and magnesium-like selenium are presented. The experimental results for the neon-like ions are compared to theoretical wavelength values and with values extrapolated along the isoelectronic sequence. The ions were contained in a plasma heated in a line-focus of a Nd-glass laser. The measurements were made with a time-gated microchannel-plate-intensified grazing incidence spectrograph.
Date: September 8, 1987
Creator: Eckart, M. J.; Scofield, J. H. & Hazi, A. U.
Partner: UNT Libraries Government Documents Department
open access

Copper-coated laser-fusion targets using molecular-beam levitation

Description: A series of diagnostic experiments at the Shiva laser fusion facility required targets of glass microspheres coated with 1.5 to 3.0 ..mu..m of copper. Previous batch coating efforts using vibration techniques gave poor results due to microsphere sticking and vacuum welding. Molecular Beam Levitation (MBL) represented a noncontact method to produce a sputtered copper coating on a single glassmicrosphere. The coating specifications that were achieved resulted in a copper layer up to 3 ..mu..m thi… more
Date: September 8, 1981
Creator: Rocke, M. J.
Partner: UNT Libraries Government Documents Department
open access

Pyrochemical processing of plutonium. Technology review report

Description: Non-aqueous processes are now in routine use for direct conversion of plutonium oxide to metal, molten salt extraction of americium, and purification of impure metals by electrorefining. These processes are carried out at elevated temperatures in either refractory metal crucibles or magnesium-oxide ceramics in batch-mode operation. Direct oxide reduction is performed in units up to 700 gram PuO/sub 2/ batch size with molten calcium metal as the reductant and calcium chloride as the reaction flu… more
Date: September 8, 1982
Creator: Coops, M.S.; Knighton, J.B. & Mullins, L.J.
Partner: UNT Libraries Government Documents Department
open access

Physics of field reversed mirrors

Description: Since the earliest days of fusion research it has been hoped that diamagnetic currents flowing in a plasma could be used to help confine the plasma. Recently this hope has been strengthened both by theoretical advances and by experimental results made possible by technological developments. On the theoretical front analytical treatments and computer simulation studies have demonstrated equilibrium solutions existing both in the fluid limit and in the large-orbit limit. Progress has also been ma… more
Date: September 8, 1978
Creator: Post, Richard F.
Partner: UNT Libraries Government Documents Department
open access

Response of Inconel 600 to simulated fusion reactor irradiation

Description: Inconel 600 was irradiated in HFIR to provide a partial simulation of fusion reactor service. Samples were irradiated at 55 to 700/sup 0/C, to investigate swelling and postirradiation tensile properties as a function of irradiation and test temperatures under conditions of concurrent displacement damage and helium production. Helium contents from 600 to 1800 appm and displacement levels of 4 to 9 dpa were achieved, and the results are used to estimate performance in a fusion reactor environment… more
Date: September 8, 1978
Creator: Wiffen, F.W.
Partner: UNT Libraries Government Documents Department
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Mirror fusion test facility

Description: The MFTF is a large new mirror facility under construction at Livermore for completion in 1981--82. It represents a scaleup, by a factor of 50 in plasma volume, a factor of 5 or more in ion energy, and a factor of 4 in magnetic field intensity over the Livermore 2XIIB experiment. Its magnet, employing superconducting NbTi windings, is of Yin-Yang form and will weigh 200 tons. MFTF will be driven by neutral beams of two levels of current and energy: 1000 amperes of 20 keV (accelerating potential… more
Date: September 8, 1978
Creator: Post, Richard F.
Partner: UNT Libraries Government Documents Department
open access

The superconducting solenoid magnet system for the GEM detector at the SSC

Description: The design of the magnet for the GEM detector at the SSC is described. It is an 18m inner diameter, 30m long superconducting solenoid, with a magnetic field of 0.8T. The basic solenoidal field is shaped by large ferromagnetic cones, to improve detector performance in the ends of the solenoid. Because of the system`s large size and mass, field-fabrication on-site at SSC is required. The challenges in this process, together with the large stored energy of the system, 2.5 GJ, have lead to novel de… more
Date: September 8, 1993
Creator: Deis, G.; Bowers, J. & Chargin, A.
Partner: UNT Libraries Government Documents Department
open access

Rep-Rated X-ray Damage and Ablation Experiments for IFE and ICF Applications

Description: The response of materials to high-dose x-ray exposures needs to be understood for inertial fusion energy (IFE) and inertial confinement fusion applications, where the requirements for IFE are considerably more stringent. In the IFE context, x-ray damage and/or small levels of ablation are of importance for component survivability, generation of debris, and contamination. Ablation quantities of even 1 angstrom per shot would result in material removal of more than 1 cm per year of operation. If … more
Date: September 8, 2003
Creator: Latkowski, J. F.; Abbott, R. P.; Payne, S. A.; Reyes, S.; Schmitt, R. C. & Speth, J. A.
Partner: UNT Libraries Government Documents Department
open access

CHIRPED PULSE AMPLIFICATION OF HGHG-FEL FACILITY AT BNL.

Description: The DUV-FEL facility has been in operation in High Gain Harmonic Generation (HGHG) mode for one year producing 266 nm output from 177 MeV electrons. In this paper we present preliminary results of the Chirped Pulse Amplification (CPA) of HGHG radiation. In the normal HGHG process, a 1 ps electron beam is seeded by chirped 9 ps long 800 nm Ti:Sapphire laser. The electron beam sees only a narrow fraction of the seed laser bandwidth. However, in the CPA case the seed laser pulse length is reduced … more
Date: September 8, 2003
Creator: DOYURAN,A. ET AL.
Partner: UNT Libraries Government Documents Department
open access

High field solenoids for muon cooling

Description: The proposed cooling system for the muon collider will consist of a 200 meter long line of alternating field straight solenoids interspersed with bent solenoids. The muons are cooled in all directions using a 400 mm long section liquid hydrogen at high field. The muons are accelerated in the forward direction by about 900 mm long, 805 MHz RF cavities in a gradient field that goes from 6 T to -6 T in about 300 mm. The high field section in the channel starts out at an induction of about 2 T in t… more
Date: September 8, 1999
Creator: Green, M. A.; Eyssa, Y.; Kenny, S.; Miller, J. R. & Prestemon, S.
Partner: UNT Libraries Government Documents Department
open access

Radiation-Hardened Gallium Nitride Detector and Arrays for Fusion Diagnostics

Description: This poster reports testing to confirm that GaN devices exhibit the extreme radiation hardness needed for use at the NIF, functioning properly after 1x10{sup 12} protons/cm{sup 2} proton irradiation in one year.
Date: September 8, 2011
Creator: Sun, K. X., and MacNeil, L.
Partner: UNT Libraries Government Documents Department
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