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GeV electron beams from cm-scale channel guided laser wakefieldaccelerator

Description: Laser-wakefield accelerators (LWFA) can produce electricfields of order 10-100 GV/m suitable for acceleration of electrons torelativistic energies. The wakefields are excited by a relativisticallyintense laser pulse propagating through a plasma and have a phasevelocity determined by the group velocity of the light pulse. Twoimportant effects that can limit the acceleration distanceand hence thenet energy gain obtained by an electron are diffraction of the drivelaser pulse and particle-wake deph… more
Date: February 20, 2007
Creator: Nakamura, K.; Nagler, B.; Toth, Cs.; Geddes, C. G. R.; Schroeder, C.; Esarey, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Applied Focused Ion Beam Techniques for Sample Preparation of Astromaterials for Integrated Nano-Analysis

Description: Sample preparation is always a critical step in study of micrometer sized astromaterials available for study in the laboratory, whether their subsequent analysis is by electron microscopy or secondary ion mass spectrometry. A focused beam of gallium ions has been used to prepare electron transparent sections from an interplanetary dust particle, as part of an integrated analysis protocol to maximize the mineralogical, elemental, isotopic and spectroscopic information extracted from one individu… more
Date: February 20, 2007
Creator: Graham, G A; Teslich, N E; Kearsley, A T; Stadermann, F J; Stroud, R M; Dai, Z R et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Senate Rule XIV Procedures for Placing Measures Directly on the Senate Calendar

Description: When a Senator introduces a bill or joint resolution, the measure is usually referred to committee, pursuant to provisions of Senate Rules XIV, XVII, and XXV. This report describes the Senate Rule XIV, para. 2, which requires that bills and resolutions have three readings before passage, and that they be read twice before being referred to committee.
Date: February 20, 2007
Creator: Koempel, Michael L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Importance of Supernovae at z<0.1 for Probing Dark Energy

Description: Supernova experiments to characterize dark energy require a well designed low redshift program; we consider this for both ongoing/near term (e.g. Supernova Legacy Survey) and comprehensive future (e.g., SNAP) experiments. The derived criteria are: a supernova sample centered near z=0.05 comprising 150-500 (in the former case) and 300-900 (in the latter case) well measured supernovae. Low redshift Type Ia supernovae play two important roles for cosmological use of the supernova distance-redshift… more
Date: February 20, 2007
Creator: Miller, Jeanne M & Linder, E.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

De Novo Identification of Regulatory Regions in Intergenic Spaces of Prokaryotic Genomes

Description: This project was begun to implement, test, and experimentally validate the results of a novel algorithm for genome-wide identification of candidate transcription-factor binding sites in prokaryotes. Most techniques used to identify regulatory regions rely on conservation between different genomes or have a predetermined sequence motif(s) to perform a genome-wide search. Therefore, such techniques cannot be used with new genome sequences, where information regarding such motifs has not yet been … more
Date: February 20, 2007
Creator: Chain, P; Garcia, E; Mcloughlin, K & Ovcharenko, I
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

HEAT OF DILUTION CALCULATION FOR 19 MOLAR SODIUM HYDROXIDE WITH WATER FOR USE IN 241-S-112

Description: High concentration caustic solutions are known to cause stress corrosion cracking in carbon steel at elevated temperature. This calculation establishes the conditions where heat of dilution will not cause the solution temperature--concentration to exceed the boundary for stress corrosion cracking as established by NACE International.
Date: February 20, 2007
Creator: Barton, W. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

THE INTEGRATION OF THE 241-Z BUILDING DECONTAMINATION & DECOMMISSIONING (D&D) UNDER COMPREHENSIVE ENVIRONMENTAL RESPONSE COMPENSATION & LIABILITY ACT (CERCLA) WITH RESOURCE CONSERVATION & RECOVERY ACT (RCRA) CLOSURE AT THE PLUTONIUM FINISHING PLANT (PFP)

Description: The 241-Z treatment and storage tanks, a hazardous waste Treatment, Storage and Disposal (TSD) unit permitted pursuant to the ''Resource Conservation and Recovery Act of 1976'' (RCRA) and Washington State ''Hazardous Waste Management Act, RCW 70.105'', have been deactivated and are being actively decommissioned. The 241-Z TSD unit managed non-listed radioactive contaminated waste water, containing trace RCRA characteristic constituents. The 241-Z TSD unit consists of below grade tanks (D-4, D-5… more
Date: February 20, 2007
Creator: HOPKINS, A.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Charting the Course for Elementary Particle Physics

Description: ''It was the best of times; it was the worst of times'' is the way Dickens begins the Tale of Two Cities. The line is appropriate to our time in particle physics. It is the best of times because we are in the midst of a revolution in understanding, the third to occur during my career. It is the worst of times because accelerator facilities are shutting down before new ones are opening, restricting the opportunity for experiments, and because of great uncertainty about future funding. My task to… more
Date: February 20, 2007
Creator: Richter, Burton
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Predicting the Cosmological Constant from the CausalEntropic Principle

Description: We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, it asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with obser… more
Date: February 20, 2007
Creator: Bousso, Raphael; Harnik, Roni; Kribs, Graham D. & Perez, Gilad
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The differentiation history of the terrestrial planets as recorded on the moon

Description: The outline for this report is: (1) Factors Leading to Lunar Magma Ocean Model for Planetary Differentiation (2) Rationale for Magma Oceans on Other Planets Means for early efficient differentiation (Works on Moon why not here?) (3) Some Inconsistencies between the Lunar Magma Ocean Model and Observations. The conclusions are: (1) Differentiation via solidification of a magma ocean is derived from geologic observations of the Moon (2) Although geologic observations on other bodies are often con… more
Date: February 20, 2007
Creator: Borg, L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

CRATES: An All-Sky Survey of Flat-Spectrum Radio Sources

Description: We have assembled an 8.4 GHz survey of bright, flat-spectrum ({alpha} > -0.5) radio sources with nearly uniform extragalactic (|b| > 10{sup o}) coverage for sources brighter than S{sub 4.8 GHz} = 65 mJy. The catalog is assembled from existing observations (especially CLASS and the Wright et al. PMN-CA survey), augmented by reprocessing of archival VLA and ATCA data and by new observations to fill in coverage gaps. We refer to this program as CRATES, the Combined Radio All-sky Targeted Eig… more
Date: February 20, 2007
Creator: Healey, Stephen E.; Romani, Roger W.; Taylor, Gregory B.; Sadler, Elaine M.; Ricci, Roberto; Murphy, Tara et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Three-Loop Superfiniteness of N=8 Supergravity

Description: We construct the three-loop four-point amplitude of N = 8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace power-counting arguments, render its degree of divergence in D dimensions to be no worse than that of N = 4 super-Yang-Mills theory--a finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N = 8 superg… more
Date: February 20, 2007
Creator: Bern, Z.; Carrasco, J.J.; Dixon, L.J.; Johansson, H.; Kosower, D.A. & Roiban, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Use of Nuclear Explosives To Disrupt or Divert Asteroids

Description: Nuclear explosives are a mature technology with well-characterized effects. Proposed utilizations include a near asteroid burst to ablate surface material and nudge the body to a safer orbit, or a direct sub-surface burst to fragment the body. For this latter method, previous estimates suggest that for times as short as 1000 days, over 99.999% of the material is diverted, and no longer impacts the Earth, a huge mitigation factor. To better understand these possibilities, we have used a multidim… more
Date: February 20, 2007
Creator: Dearborn, D. S.; Patenaude, S. & Managan, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Physical Renormalization of Quantum Field Theories

Description: The profound revolutions in particle physics likely to emerge from current and future experiments motivates an improved understanding of the precise predictions of the Standard Model and new physics models. Higher order predictions in quantum field theories inevitably requires the renormalization procedure, which makes sensible predictions out of the naively divergent results of perturbation theory. Thus, a robust understanding of renormalization is crucial for identifying and interpreting the … more
Date: February 20, 2007
Creator: Binger, Michael William.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Clipping: Gergen to speak at luncheon]

Description: Newspaper clipping describes David Gergen addressing the Planned Parenthood of North Texas luncheon to raise money. According to the article, Gergen is a professor at Harvard's John F. Kennedy School of Government and has worked as an advisor to Nixon, Ford, Reagan, and Clinton administrations. There are red markings in pen.
Date: February 20, 2007
Creator: Miller, Robert
Item Type: Refine your search to only Clipping
Partner: UNT Libraries Special Collections
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