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1.5-GEV FFAG ACCELERATOR AS INJECTOR TO THE BNL-AGS.

Description: A 1.5-GeV Fixed-Field Alternating-Gradient (FFAG) proton Accelerator is being studied as a new injector to the Alternating-Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). The major benefit is that it would considerably shorten the overall AGS acceleration cycle, and, consequently, may yield to an improvement of beam stability, intensity and size. The AGS-FFAG will also facilitate the proposed upgrade of the AGS facility toward a 1-MW average proton beam power at the top ener… more
Date: July 5, 2004
Creator: Ruggiero, A. G.; Blaskiewicz, M.; Trbojevic, D.; Tsoupas, N. & Zhang, W.
Partner: UNT Libraries Government Documents Department
open access

1 MeV electron irradiation of solid Xe nanoclusters in Al : an in-situ HRTEM study.

Description: Thin film samples of a simple embedded nanocluster system consisting of solid Xe precipitates in Al have been subjected to 1 MeV electron irradiation in a high-voltage electron microscope. High-resolution images have been recorded on videotape in order to monitor the changes to the system resulting from the passage of electrons through the film. Inspection of the video recordings (in some cases frame-by-frame) reveals that complex, rapid processes occur under the electron beam. These include, m… more
Date: December 5, 1997
Creator: Donnelly, S. E.; Furuya, K.; Song, M.; Birtcher, R. C. & Allen, C. W.
Partner: UNT Libraries Government Documents Department
open access

A 4 to 0.1 nm FEL Based on the SLAC Linac

Description: The author show that using existing electron gun technology and a high energy linac like the one at SLAC, it is possible to build a Free Electron Laser operating around the 4 nm water window. A modest improvement in the gun performance would further allow to extend the FEL to the 0.1 nm region. Such a system would produce radiation with a brightness many order of magnitude above that of any synchrotron radiation source, existing or under construction, with laser power in the multigawatt region … more
Date: June 5, 2012
Creator: Pellegrini, C.
Partner: UNT Libraries Government Documents Department
open access

10 (micro)m and 5 (micro)m Pinhole-Assisted Point-Projection Backlit Imaging for NIF

Description: Pinhole-assisted point-projection backlighting with 10{micro}m and 5 {micro}m pinholes placed a small distance of order 1 mm away from the backlighter produces images with large field of view and high resolution. Pinholes placed closely to high-power backlighter sources can vaporize and close due to x-ray driven ablation, thereby limiting the usefulness of this method. A study of streaked 1-D backlit imaging of 25 {micro}m W wires using the OMEGA laser is presented. The pinhole closure timescal… more
Date: June 5, 2001
Creator: Bullock, A. B.; Landen, O. L. & Bradley, D. K.
Partner: UNT Libraries Government Documents Department
open access

A 30 ps Timing Resolution for Single Photons with Multi-pixel Burle MCP-PMT

Description: We have achieved {approx}30 psec single-photoelectron and {approx}12ps for multi-photoelectron timing resolution with a new 64 pixel Burle MCP-PMT with 10 micron microchannel holes. We have also demonstrated that this detector works in a magnetic field of 15kG, and achieved a single-photoelectron timing resolution of better than 60 psec. The study is relevant for a new focusing DIRC RICH detector for particle identification at future Colliders such as the super B-factory or ILC, and for future … more
Date: July 5, 2006
Creator: Va'vra, J.; Benitez, J.; Coleman, J.; Leith, D. W. G. S.; Mazaheri, G.; Ratcliff, B. et al.
Partner: UNT Libraries Government Documents Department
open access

62-TeV center of mass hadron collider with superbunch beams

Description: The scheme of a 62-TeV center of mass p-p collider with superbunch beams at Fermilab is proposed as a practical and realistically achievable future project. It will be built in two stages, using the same tunnel, first with a 2 Tesla low field magnet collider ring and later with a 10 Tesla high field magnet collider ring. Both low and high field magnets have twin bore aperture and will be installed in the tunnel with the circumference of 87.25 km. In each bore a proton beam is accelerated, using… more
Date: November 5, 2001
Creator: al., Ryuji Yamada et
Partner: UNT Libraries Government Documents Department
open access

80 HP PLASMA ASSISTED CATALYST SYSTEM

Description: The US economy is linked to efficient heavy vehicle transportation and diesel remains the fuel of choice for mass transportation of goods and services. Diesel engines remain the most reliable and cost effective system for commerce. Recent deleterious effects of diesel exhaust on health and environment have led to an urgent need for cost effective technologies that would bring about reduction in NOx and PM. CARB estimates on-road diesel mobile source will contribute almost 50% NOx and 78% PM emi… more
Date: August 5, 2001
Creator: Slone, Ralph
Partner: UNT Libraries Government Documents Department
open access

14C/C measurements support Andreev's internode method to determine lichen growth rates in Cladina stygia (Fr.) Ahti

Description: Growth rates and the ability to date an organism can greatly contribute to understanding its population biology and community dynamics. 1n 1954, Andreev proposed a method to date Cladina, a fruticose lichen, using total thallus length and number of internodes. No research, however, has demonstrated the reliability of this technique or compared its estimates to those derived by other means. In this study, we demonstrate the utility of {sup 14}C/C ratios to determine lichen age and growth rate in… more
Date: December 5, 2007
Creator: Holt, E. & Bench, G.
Partner: UNT Libraries Government Documents Department
open access

The 1997/98 El Nino: A Test for Climate Models

Description: Version 3 of the Hadley Centre Atmospheric Model (HadAM3) has been used to demonstrate one means of comparing a general circulation model with observations for a specific climate perturbation, namely the strong 1997/98 El Nino. This event was characterized by the collapse of the tropical Pacific's Walker circulation, caused by the lack of a zonal sea surface temperature gradient during the El Nino. Relative to normal years, cloud altitudes were lower in the western portion of the Pacific and hi… more
Date: March 5, 2004
Creator: Lu, R; Dong, B; Cess, R D & Potter, G L
Partner: UNT Libraries Government Documents Department
open access

2007 Nuclear Data Review

Description: The results of a review and evaluation of neutron and non-neutron nuclear data published in the scientific literature are presented. The status of new chemical elements is examined. Data on revised values for the isotopic composition of the elements are reviewed and recommended values are presented. Half-lives of very long-lived nuclides are presented, including double beta decay, double electron capture, long-lived alpha decay and long-lived beta decay. Data from new measurements on the very h… more
Date: May 5, 2008
Creator: Holden, N. E.
Partner: UNT Libraries Government Documents Department
open access

2011 Archaea: Ecology, Metabolism, & Molecular Biology

Description: Archaea, one of three major evolutionary lineages of life, are a fascinating and diverse group of microbes with deep roots overlapping those of eukaryotes. The focus of the 'Archaea: Ecology Metabolism & Molecular Biology' GRC conference expands on a number of emerging topics highlighting new paradigms in archaeal metabolism, genome function and systems biology; information processing; evolution and the tree of life; the ecology and diversity of archaea and their viruses. The strength of this c… more
Date: August 5, 2011
Creator: Stedman, Keneth
Partner: UNT Libraries Government Documents Department
open access

2011 Quantum Control of Light & Matter Gordon Research Conference (July 31-August 5, 2011, Mount Holyoke College, South Hadley, MA)

Description: Quantum control of light and matter is the quest to steer a physical process to a desirable outcome, employing constructive and destructive interference. Three basic questions address feasibility of quantum control: (1) The problem of controllability, does a control field exist for a preset initial and target state; (2) Synthesis, constructively finding the field that leads to the target; and (3) Optimal Control Theory - optimizing the field that carries out this task. These continue to be the … more
Date: August 5, 2011
Creator: Weinacht, Thomas
Partner: UNT Libraries Government Documents Department
open access

23rd IAEA Fusion Energy Conference: Summary Of Sessions EX/C and ICC

Description: An overview is given of recent experimental results in the areas of innovative confinement concepts, operational scenarios and confinement experiments as presented at the 2010 IAEA Fusion Energy Conference. Important new findings are presented from fusion devices worldwide, with a strong focus towards the scientific and technical issues associated with ITER and W7-X devices, presently under construction.
Date: January 5, 2011
Creator: Hawryluk, Richard J.
Partner: UNT Libraries Government Documents Department
open access

2w Laser Propagation and Raman Backscatter in Underdense Gas Bag Plasmas

Description: Recent 2{omega} gasbag experiments on the Helen laser studied single-beam propagation and backscatter as a function of gas density. We present a comprehensive analysis of these experiments using simulations in HYDRA. Post-processed results agree well with experimental fast x-ray images (FXI) showing stable laser propagation across the bag. The measured total stimulated Raman backscatter (SRS) increases with initial gas density up to n{sub e} {approx} 0.08 n{sub c}, then decreases. Near-backscat… more
Date: September 5, 2003
Creator: Meezan, N.; Divol, L.; Suter, L.; Miller, M.; Stevenson, R. M.; Slark, G. et al.
Partner: UNT Libraries Government Documents Department
open access

3D-Simulation Studies of SNS Ring Doublet Magnets

Description: The accumulator ring of the Spallation Neutron Source (SNS) at ORNL employs in its straight sections closely packed quadrupole doublemagnets with large aperture of R=15.1 cm an relatively short iron-to-iron distance of 51.4 cm. These quads have much extended fringe field, and magnetic interferences among them in the doublet assemblies is not avoidable. Though each magnet in the assemblies has been individually mapped to high accuracy of lower than 0.01 percent level, the experimental data inclu… more
Date: May 5, 2005
Creator: Wang, J. G.; N., Tsoupas & Venturini, M.
Partner: UNT Libraries Government Documents Department
open access

3D Simulations of the NIF Indirect Drive Ignition Target Design

Description: The radiation hydrodynamics code Hydra is used to quantify the sensitivity of different NIF ignition point designs to several 3D effects. Each of the 48 NIF quads is included in the calculations and is allowed to have different power. With this model they studied the effect on imploded core symmetry of discrete laser spots (as opposed to idealized azimuthally-averaged rings) and random variations in laser power.
Date: January 5, 2010
Creator: Jones, O. S.; Milovich, J. L.; Callahan, D. A.; Edwards, M. J.; Landen, O. L.; Salmonson, J. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Aberration correction for analytical in situ TEM - the NTEAM concept.

Description: Future aberration corrected transmission electron microscopes (TEM) will have a strong impact in materials science, since such microscopes yield information on chemical bonding and structure of interfaces, grain boundaries and lattice defects at an atomic level. Beyond this aberration correction offers new possibilities for in situ experiments performed under controlled temperature, magnetic field, strain etc. at atomic resolution. Such investigations are necessary for solving problems arising … more
Date: March 5, 2002
Creator: Kabius, B.; Allen, C. W. & Miller, D. J.
Partner: UNT Libraries Government Documents Department
open access

Abraham Solvation Parameter Model: Calculation of L Solute Descriptors for Large C11 to C42 Methylated Alkanes from Measured Gas–Liquid Chromatographic Retention Data

Description: This article determines Abraham model L solute descriptors for 149 additional C11 to C42 monomethylated and polymethylated alkanes based on published Kovat’s retention indices based upon gas–liquid chromatographic measurements.
Date: July 5, 2022
Creator: Wu, Emily; Sinha, Sneha; Yang, Chelsea; Zhang, Miles & Acree, William E. (William Eugene)
Partner: UNT College of Science
open access

Abstract: Contaminant Travel Times From the Nevada Test Site to Yucca Mountain: Sensitivity to Porosity

Description: Yucca Mountain (YM), Nevada, has been proposed by the U.S. Department of Energy as a geologic repository for spent nuclear fuel and high-level radioactive waste. In this study, we investigate the potential for groundwater advective pathways from underground nuclear testing areas on the Nevada Test Site (NTS) to the YM area by estimating the timeframe for advective travel and its uncertainty resulting from porosity value uncertainty for hydrogeologic units (HGUs) in the region. We perform sensit… more
Date: September 5, 2008
Creator: Pohlmann, Karl F.; Zhu, Jianting; Chapman, Jenny B.; Russell, Charles E.; Carroll, Rosemary W. H. & Shafer, David S.
Partner: UNT Libraries Government Documents Department
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