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World Sheet Commuting beta-gamma CFT and Non-Relativistic StringTheories (open access)

World Sheet Commuting beta-gamma CFT and Non-Relativistic StringTheories

We construct a sigma model in two dimensions with Galilean symmetry in flat target space similar to the sigma model of the critical string theory with Lorentz symmetry in 10 flat spacetime dimensions. This is motivated by the works of Gomis and Ooguri[1] and Danielsson et. al.[2, 3]. Our theory is much simpler than their theory and does not assume a compact coordinate. This non-relativistic string theory has a bosonic matter {beta}{gamma} CFT with the conformal weight of {beta} as 1. It is natural to identify time as a linear combination of {gamma} and {bar {gamma}} through an explicit realization of the Galilean boost symmetry. The angle between {gamma} and {bar {gamma}} parametrizes one parameter family of selection sectors. These selection sectors are responsible for having a non-relativistic dispersion relation without a nontrivial topology in the non-relativistic setup, which is one of the major differences from the previous works[1, 2, 3]. This simple theory is the non-relativistic analogue of the critical string theory, and there are many different avenues ahead to be investigated. We mention a possible consistent generalization of this theory with different conformal weights for the {beta}{gamma} CFT. We also mention supersymmetric generalizations of these theories.
Date: August 30, 2007
Creator: Kim, Bom Soo
Object Type: Article
System: The UNT Digital Library
Overview of the National Ignition Facility (open access)

Overview of the National Ignition Facility

The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory will be the world's largest and most powerful laser system for inertial confinement fusion (ICF) and experiments studying high energy density (HED) science. NIF is a 192 beam Nd-glass laser facility that will produce 1.8 MJ, 500 TW of ultraviolet light making it over fifty times more energetic than present ICF facilities. The NIF Project began in 1995 and is scheduled for completion in 2009. Ignition experiments on NIF, which will use tritium, are scheduled to begin in 2010. Tritium will arrive at the facility in individual target assemblies. The assemblies will be mounted to the Cryogenic TARget POSitioner (TARPOS), which provides the cryogenic cooling systems necessary to complete the formation of the ignition target's fuel ice layer. It also provides the positioning system that transports and holds the target at the center of the NIF chamber during a shot. After a shot, unburned tritium will be captured by the cryopumps. Upon regeneration, the cryopump effluent will be directed to the Tritium Processing System, part of NIF's. Personnel and Environmental Protection Systems. These systems also include, local contamination control systems, area and stack tritium monitoring systems, a decontamination area, and …
Date: August 30, 2007
Creator: Moses, Edward
Object Type: Article
System: The UNT Digital Library
TASI Lectures on the cosmological constant (open access)

TASI Lectures on the cosmological constant

The energy density of the vacuum, Lambda, is at least 60 orders of magnitude smaller than several known contributions to it. Approaches to this problem are tightly constrained by data ranging from elementary observations to precision experiments. Absent overwhelming evidence to the contrary, dark energy can only be interpreted as vacuum energy, so the venerable assumption that Lambda=0 conflicts with observation. The possibility remains that Lambda is fundamentally variable, though constant over large spacetime regions. This can explain the observed value, but only in a theory satisfying a number of restrictive kinematic and dynamical conditions. String theory offers a concrete realization through its landscape of metastable vacua.
Date: August 30, 2007
Creator: Bousso, Raphael & Bousso, Raphael
Object Type: Article
System: The UNT Digital Library
Mechanical and Electrical Properties of CdTe Tetrapods Studied byAtomic Force Microscopy (open access)

Mechanical and Electrical Properties of CdTe Tetrapods Studied byAtomic Force Microscopy

The mechanical and electrical properties of CdTe tetrapod-shaped nanocrystals have been studied with atomic force microscopy. Tapping mode images of tetrapods deposited on silicon wafers revealed that they contact the surface with the ends of three arms. The length of these arms was found to be 130 {+-} 10 nm. A large fraction of the tetrapods had a shortened vertical arm as a result of fracture during sample preparation. Fracture also occurs when the applied load is a few nanonewtons. Compression experiments with the AFM tip indicate that tetrapods with the shortened vertical arm deform elastically when the applied force was less than 50 nN. Above 90 nN additional fracture events occurred that further shorted the vertical arm. Loads above 130 nN produced irreversible damage to the other arms as well. Current-voltage characteristics of tetrapods deposited on gold indicated semiconducting behavior with a current gap of {approx}2 eV at low loads (<50 nN) and a narrowing to about 1 eV at loads between 60 and 110 nN. Atomic calculation of the deformation suggests that the ends of the tetrapod arms are stuck during compression so that the deformations are due to bending modes. The reduction of the current gap is …
Date: August 30, 2007
Creator: Fang, Liang; Park, Jeong Young; Cui, Yi; Alivisatos, Paul; Shcrier, Joshua; Lee, Byounghak et al.
Object Type: Article
System: The UNT Digital Library
Characterization and Actual Waste Test With Tank 5f Samples (open access)

Characterization and Actual Waste Test With Tank 5f Samples

The initial phase of bulk waste removal operations was recently completed in Tank 5F. Video inspection of the tank indicates several mounds of sludge still remain in the tank. Additionally, a mound of white solids was observed under Riser 5. In support of chemical cleaning and heel removal programs, samples of the sludge and the mound of white solids were obtained from the tank for characterization and testing. A core sample of the sludge and Super Snapper sample of the white solids were characterized. A supernate dip sample from Tank 7F was also characterized. A portion of the sludge was used in two tank cleaning tests using oxalic acid at 50 C and 75 C. The filtered oxalic acid from the tank cleaning tests was subsequently neutralized by addition to a simulated Tank 7F supernate. Solids and liquid samples from the tank cleaning test and neutralization test were characterized. A separate report documents the results of the gas generation from the tank cleaning test using oxalic acid and Tank 5F sludge. The characterization results for the Tank 5F sludge sample (FTF-05-06-55) appear quite good with respect to the tight precision of the sample replicates, good results for the glass standards, …
Date: August 30, 2007
Creator: Fletcher, D.
Object Type: Report
System: The UNT Digital Library
Final Report: Model interacting particle systems for simulation and macroscopic description of particulate suspensions (open access)

Final Report: Model interacting particle systems for simulation and macroscopic description of particulate suspensions

Suspensions of solid particles in liquids appear in numerous applications, from environmental settings like river silt, to industrial systems of solids transport and water treatment, and biological flows such as blood flow. Despite their importance, much remains unexplained about these complicated systems. Mucha's research aims to improve understanding of basic properties of suspensions through a program of simulating model interacting particle systems with critical evaluation of proposed continuum equations, in close collaboration with experimentalists. Natural to this approach, the original proposal centered around collaboration with studies already conducted in various experimental groups. However, as was detailed in the 2004 progress report, following the first year of this award, a number of the questions from the original proposal were necessarily redirected towards other specific goals because of changes in the research programs of the proposed experimental collaborators. Nevertheless, the modified project goals and the results that followed from those goals maintain close alignment with the main themes of the original proposal, improving efficient simulation and macroscopic modeling of sedimenting and colloidal suspensions. In particular, the main investigations covered under this award have included: (1) Sedimentation instabilities, including the sedimentation analogue of the Rayleigh-Taylor instability (for heavy, particle-laden fluid over lighter, clear …
Date: August 30, 2007
Creator: Mucha, Peter J.
Object Type: Report
System: The UNT Digital Library
Remaining Sites Verification Package for the 1607-B1 Septic System, Waste Site Reclassification Form 2007-015 (open access)

Remaining Sites Verification Package for the 1607-B1 Septic System, Waste Site Reclassification Form 2007-015

The 1607-B1 Septic System includes a septic tank, drain field, and associated connecting pipelines and influent sanitary sewer lines. This septic system serviced the former 1701-B Badgehouse, 1720-B Patrol Building/Change Room, and the 1709-B Fire Headquarters. The 1607-B1 waste site received unknown amounts of nonhazardous, nonradioactive sanitary sewage from these facilities during its operational history from 1944 to approximately 1970. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: August 30, 2007
Creator: Dittmer, L. M.
Object Type: Report
System: The UNT Digital Library
Rayleigh-Taylor Shock Waves (open access)

Rayleigh-Taylor Shock Waves

Beginning from a state of hydrostatic equilibrium, in which a heavy gas rests atop a light gas in a constant gravitational field, Rayleigh-Taylor instability at the interface will launch a shock wave into the upper fluid. The rising bubbles of lighter fluid act like pistons, compressing the heavier fluid ahead of the fronts and generating shocklets. These shocklets coalesce in multidimensional fashion into a strong normal shock, which increases in strength as it propagates upwards. Large-eddy simulations demonstrate that the shock Mach number increases faster in three dimensions than it does in two dimensions. The generation of shocks via Rayleigh-Taylor instability could have profound implications for astrophysical flows.
Date: August 30, 2007
Creator: Olson, B J & Cook, A W
Object Type: Article
System: The UNT Digital Library
Characterization and Actual Waste Tests With Tank 5F Samples (open access)

Characterization and Actual Waste Tests With Tank 5F Samples

This report addresses the characterization and actual waste tests with tank 5F samples.
Date: August 30, 2007
Creator: Hay, M; Kim Crapse, K; Samuel Fink, S & John Pareizs, J
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 38, No. 356, Ed. 1 Thursday, August 30, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 356, Ed. 1 Thursday, August 30, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 30, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 357, Ed. 1 Thursday, August 30, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 357, Ed. 1 Thursday, August 30, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 30, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
[Historic Marker Application: Guthrie Building] (open access)

[Historic Marker Application: Guthrie Building]

Application materials submitted to the Texas Historical Commission requesting a historic marker for the Guthrie Building, in Kerrville, Texas. The materials include the inscription text of the marker, original application, narrative, floor plans, and photographs.
Date: August 30, 2007
Creator: Texas Historical Commission
Object Type: Text
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 1, Ed. 1 Thursday, August 30, 2007 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 1, Ed. 1 Thursday, August 30, 2007

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: August 30, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Texas Jewish Post (Fort Worth, Tex.), Vol. 61, No. 35, Ed. 1 Thursday, August 30, 2007 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 61, No. 35, Ed. 1 Thursday, August 30, 2007

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state and national news along with extensive advertising.
Date: August 30, 2007
Creator: Wisch, Rene
Object Type: Newspaper
System: The Portal to Texas History
The Bastrop Advertiser (Bastrop, Tex.), Vol. 154, No. 53, Ed. 1 Thursday, August 30, 2007 (open access)

The Bastrop Advertiser (Bastrop, Tex.), Vol. 154, No. 53, Ed. 1 Thursday, August 30, 2007

Semi-weekly newspaper from Bastrop, Texas that includes local, state and national news along with advertising.
Date: August 30, 2007
Creator: McAuley, Davis
Object Type: Newspaper
System: The Portal to Texas History
Congressional Salaries and Allowances (open access)

Congressional Salaries and Allowances

This report provides basic information on congressional salaries and allowances. The report briefly summarizes the current salary of Members of Congress, limits on their outside earned income and honoraria, and applicable health insurance and retirement benefits. The report also provides information on allowances available to Representatives and Senators. Lastly, this report lists the salaries of congressional officers and officials and committee staff.
Date: August 30, 2007
Creator: Brudnick, Ida A.
Object Type: Report
System: The UNT Digital Library
Andean Counterdrug Initiative (ACI) and Related Funding Programs: FY2007 Assistance (open access)

Andean Counterdrug Initiative (ACI) and Related Funding Programs: FY2007 Assistance

This report is about the Andean Counterdrug Initiative (ACI) and related Funding Programs in the fiscal year 2007.
Date: August 30, 2007
Creator: Veillete, Connie
Object Type: Report
System: The UNT Digital Library
Federal Credit Reform: Implementation Of the Changed Budgetary Treatment of Direct Loans and Loan Guarantees (open access)

Federal Credit Reform: Implementation Of the Changed Budgetary Treatment of Direct Loans and Loan Guarantees

None
Date: August 30, 2007
Creator: Bickley, James M.
Object Type: Report
System: The UNT Digital Library
National Emergency Powers (open access)

National Emergency Powers

None
Date: August 30, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 37, No. 35, Ed. 1 Thursday, August 30, 2007 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 37, No. 35, Ed. 1 Thursday, August 30, 2007

Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with extensive advertising.
Date: August 30, 2007
Creator: Judson, Mary Henkel
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Fort Worth, Tex.), Vol. 31, No. 144, Ed. 1 Thursday, August 30, 2007 (open access)

Greensheet (Fort Worth, Tex.), Vol. 31, No. 144, Ed. 1 Thursday, August 30, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 30, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Albany News (Albany, Tex.), Vol. 132, No. 14, Ed. 1 Thursday, August 30, 2007 (open access)

The Albany News (Albany, Tex.), Vol. 132, No. 14, Ed. 1 Thursday, August 30, 2007

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: August 30, 2007
Creator: Lucas, Melinda L.
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Fort Worth, Tex.), Vol. 31, No. 145, Ed. 1 Thursday, August 30, 2007 (open access)

Greensheet (Fort Worth, Tex.), Vol. 31, No. 145, Ed. 1 Thursday, August 30, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 30, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 31, No. 143, Ed. 1 Thursday, August 30, 2007 (open access)

The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 31, No. 143, Ed. 1 Thursday, August 30, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 30, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History