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A Measurement of the Spatial Distribution of Diffuse TeV Gamma Ray Emission from the Galactic Plane with Milagro (open access)

A Measurement of the Spatial Distribution of Diffuse TeV Gamma Ray Emission from the Galactic Plane with Milagro

Diffuse {gamma}-ray emission produced by the interaction of cosmic-ray particles with matter and radiation in the Galaxy can be used to probe the distribution of cosmic rays and their sources in different regions of the Galaxy. With its large field of view and long observation time, the Milagro Gamma Ray Observatory is an ideal instrument for surveying large regions of the Northern Hemisphere sky and for detecting diffuse {gamma}-ray emission at very high energies. Here, the spatial distribution and the flux of the diffuse {gamma}-ray emission in the TeV energy range with a median energy of 15 TeV for Galactic longitudes between 30{sup o} and 110{sup o} and between 136{sup o} and 216{sup o} and for Galactic latitudes between -10{sup o} and 10{sup o} are determined. The measured fluxes are consistent with predictions of the GALPROP model everywhere except for the Cygnus region (l {element_of} [65{sup o}, 85{sup o}]). For the Cygnus region, the flux is twice the predicted value. This excess can be explained by the presence of active cosmic ray sources accelerating hadrons which interact with the local dense interstellar medium and produce gamma rays through pion decay.
Date: May 14, 2008
Creator: Abdo, A. A.; Allen, B.; Aune, T.; Berley, D.; Blaufuss, E.; Casanova, S. et al.
Object Type: Article
System: The UNT Digital Library
HCCI Combustion: Analysis and Experiments (open access)

HCCI Combustion: Analysis and Experiments

Homogeneous charge compression ignition (HCCI) is a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low NOx and particulate matter emissions. This paper describes the HCCI research activities being currently pursued at Lawrence Livermore National Laboratory and at the University of California Berkeley. Current activities include analysis as well as experimental work. On analysis, we have developed two powerful tools: a single zone model and a multi-zone model. The single zone model has proven very successful in predicting start of combustion and providing reasonable estimates for peak cylinder pressure, indicated efficiency and NOX emissions. This model is being applied to develop detailed engine performance maps and control strategies, and to analyze the problem of engine startability. The multi-zone model is capable of very accurate predictions of the combustion process, including HC and CO emissions. The multi-zone model h as applicability to the optimization of combustion chamber geometry and operating conditions to achieve controlled combustion at high efficiency and low emissions. On experimental work, we have done a thorough evaluation of operating conditions in a 4-cylinder Volkswagen TDI engine. The engine has been operated over a wide range of conditions by adjusting the …
Date: May 14, 2001
Creator: Aceves, Salvador M.; Flowers, Daniel L.; Martinez-Frias, Joel; Smith, J. Ray; Dibble, Robert; Au, Michael et al.
Object Type: Article
System: The UNT Digital Library
U.S.-European Union Relations and the 2007 Summit (open access)

U.S.-European Union Relations and the 2007 Summit

This report evaluates the results of the annual U.S.-EU summit on April 30, 2007, in Washington, DC.
Date: May 14, 2007
Creator: Ahearn, Raymond; Archick, Kristin & Belkin, Paul
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 28, No. 18, Ed. 1 Thursday, May 14, 2009 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 28, No. 18, Ed. 1 Thursday, May 14, 2009

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: May 14, 2009
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 106, No. 38, Ed. 1 Friday, May 14, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 38, Ed. 1 Friday, May 14, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: May 14, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Branching Fractions and CP-Violating Asymmetries in Radiative B Decays to eta K gamma (open access)

Branching Fractions and CP-Violating Asymmetries in Radiative B Decays to eta K gamma

The authors present measurements of the CP-violation parameters S and C for the radiative decay B{sup 0} {yields} {eta}K{sub S}{sup 0}{gamma}; for B {yields} {eta}K{gamma} they also measure the branching fractions and for B{sup +} {yields} {eta}K{sup +}{gamma} the time-integrated charge asymmetry {Alpha}{sub ch}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The results are S = -0.18{sub -0.46}{sup +0.49} {+-} 0.12, C = -0.32{sub -0.39}{sup +0.40} {+-} 0.07, {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = (7.1{sub -2.0}{sup +2.1} {+-} 0.4) x 10{sup -6}, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = (7.7 {+-} 1.0 {+-} 0.4) x 10{sup -6}, and {Alpha}{sub ch} = (-9.0{sub -9.8}{sup +10.4} {+-} 1.4) x 10{sup -2}. The first error quoted is statistical and the second systematic.
Date: May 14, 2008
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Observation of B+ to b_1+K0 and Search for B-meson Decays to b_10K0 and b_1pi0 (open access)

Observation of B+ to b_1+K0 and Search for B-meson Decays to b_10K0 and b_1pi0

We present the results of searches for decays of B mesons to final states with a b{sub 1} meson and a neutral pion or kaon. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The results for the branching fractions are, in units of 10{sup -6}, {Beta}(B{sup +} {yields} b{sub 1}{sup +}K{sup 0}) = 9.6 {+-} 1.7 {+-} 0.9, {Beta}(B{sup 0} {yields} b{sub 1}{sup 0}K{sup 0}) = 5.1 {+-} 1.8 {+-} 0.5 (< 7.8), {Beta}(B{sup +} {yields} b{sub 1}{sup +} {pi}{sup 0}) = 1.8 {+-} 0.9 {+-} 0.2 (<3.3), and {Beta}(B{sup 0} {yields} b{sub 1}{sup 0}{pi}{sup 0}) = 0.4 {+-} 0.8 {+-} 0.2 (<1.9), with the assumption that {Beta}(b{sub 1} {yields} {omega}{pi}) = 1. They also measure the charge asymmetry {Alpha}{sub ch} (B{sup +} {yields} b{sub 1}{sup +}K{sup 0}) = -0.03 {+-} 0.15 {+-} 0.02. The first error quoted is statistical, the second systematic, and the upper limits in parentheses indicate the 90% confidence level.
Date: May 14, 2008
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Effect of angular momentum on Valence-Quark Helicity Distributions (open access)

Effect of angular momentum on Valence-Quark Helicity Distributions

None
Date: May 14, 2007
Creator: Avakian, Harut; Brodsky, Stanley J.; Deur, Alexandre & Yuan, Feng
Object Type: Article
System: The UNT Digital Library
Q1Report for CADWR Project: Desalination Using Carbon NAnotube Membranes (open access)

Q1Report for CADWR Project: Desalination Using Carbon NAnotube Membranes

In this research and development project, LLNL will leverage the process for fabrication of the membranes developed by our internally funded effort (LLNL Laboratory Directed Research and Development). LLNL will then employ chemical manipulations to modify charge at the ends of the nanotubes and make the membranes more selective to either positive or negative ions through a combination of size and charge selectivity. LLNL's goal is to demonstrate ion exclusion while preserving high permeabilities and low energy use. Success of this research and development project may warrant further developments in the fabrication of membranes.
Date: May 14, 2008
Creator: Bakajin, O
Object Type: Report
System: The UNT Digital Library
Thermal and Chemical Analyses of Silicone Polymers for Component Engineering Lifetime Assessments (open access)

Thermal and Chemical Analyses of Silicone Polymers for Component Engineering Lifetime Assessments

Accurate predictions of a polymer component's functional lifetime at best arc tenuous when one has only relatively short term chemical or mechanical property data to extrapolate. We have analyzed a series of silica-filled siloxanes to determine the chemical and microstructural signatures of aging, and we are incorporating these data into rational methodologies for assessing a component's lifetime measured against as-designed engineering properties. We are monitoring changes in mechanical properties, crystallization kinetics, cross-link density changes, and motional dynamics with a variety of analysis methods: Modulated DSC, Dynamic Mechanical Analysis, and Solid-state Nuclear Magnetic Resonance. Previous work has shown that the addition of phenyl side groups to polydimethylsiloxane (PDMS) polymer chains reduces the rate and extent of crystallization of the co-polymer compared to that of pure PDMS. Crystallization has been observed in copolymer systems up to 6.5 mol % phenyl composition by DSC and up to 8 mol % phenyl by XRD. The PDMS-PDPS-silica composite materials studied here are silica reinforced random block copolymers consisting of dimethyl and diphenyl monomer units with 11.2 mol. % polydiphenylsiloxane. Based on this previous work, it is not expected that this material would exhibit crystallization in the polymer network; however, these silicones do, in fact, exhibit …
Date: May 14, 2002
Creator: Balazs, B & Maxwell, R S
Object Type: Article
System: The UNT Digital Library
Strategic Petroleum Reserve (open access)

Strategic Petroleum Reserve

None
Date: May 14, 2002
Creator: Bamberger, Robert L.
Object Type: Report
System: The UNT Digital Library
Gaining analytical control of parton showers (open access)

Gaining analytical control of parton showers

None
Date: May 14, 2007
Creator: Bauer, Christian W. & Tackmann, Frank J.
Object Type: Article
System: The UNT Digital Library
Addendum to the 200 West Area Dust Mitigation Strategies: Treatment of the Dust Source Area (open access)

Addendum to the 200 West Area Dust Mitigation Strategies: Treatment of the Dust Source Area

This document describes the source area for the blowing dust encountered in the southwest portion of the 200 West Area. Strategies for short-term stabilization of the entire source area, short-term stabilization of a portion of the source area based on levels of respirable dust, and long-term stabilization of the entire source area are provided. An separate evaluation of aerosolized water as a means of reducing airborne dust is also provided.
Date: May 14, 2001
Creator: Becker, James M. & Sackschewsky, Michael R.
Object Type: Report
System: The UNT Digital Library
Gasoline Prices: Legislation in the 110th Congress (open access)

Gasoline Prices: Legislation in the 110th Congress

This report gives information related to the high prices of Gasoline and legislation in the 110th Congress.
Date: May 14, 2008
Creator: Behrens, Carl E. & Glover, Carol
Object Type: Report
System: The UNT Digital Library
Exact seismic velocities for VTI and HTI media and extendedThomsen Formulas for stronger anisotropies (open access)

Exact seismic velocities for VTI and HTI media and extendedThomsen Formulas for stronger anisotropies

I explore a different type of approximation to the exactanisotropic wave velocities as a function of incidence angle invertically transversely isotropic (VTI) media. This method extends theThomsen weak anisotropy approach to stronger anisotropy withoutsignificantly affecting the simplicity of the formulas. One importantimprovement is that the peak of the quasi-SV-wave speed vsv(theta) islocated at the correct incidence angle theta= theta max, rather thanalways being at the position theta = 45o, which universally holds forThomsen's approximation although max theta = 45o is actually nevercorrect for any VTI anisotropic medium. The magnitudes of all the wavespeeds are also more closely approximated for all values of the incidenceangle. Furthermore, the value of theta max (which is needed in the newformulas) can be deduced from the same data that are typically used inthe weak anisotropy data analysis. The two examples presented are basedon systems having vertical fractures. The first set of model fractureshas their axes of symmetry randomly oriented in the horizontal plane.Such a system is then isotropic in the horizontal plane and, therefore,exhibits vertical transverse isotropic (VTI) symmetry. The second set offractures also has axes of symmetry in the horizontal plane, but it isassumed these axes are aligned so that the system exhibits horizontaltransverse …
Date: May 14, 2007
Creator: Berryman, J.G.
Object Type: Article
System: The UNT Digital Library
Seismic waves in rocks with fluids and fractures (open access)

Seismic waves in rocks with fluids and fractures

Seismic wave propagation through the earth is often stronglyaffected by the presence of fractures. When these fractures are filledwith fluids (oil, gas, water, CO2, etc.), the type and state of the fluid(liquid or gas) can make a large difference in the response of theseismic waves. This paper summarizes recent work on methods ofdeconstructing the effects of fractures, and any fluids within thesefractures, on seismic wave propagation as observed in reflection seismicdata. One method explored here is Thomsen's weak anisotropy approximationfor wave moveout (since fractures often induce elastic anisotropy due tononuniform crack-orientation statistics). Another method makes use ofsome very convenient fracture parameters introduced previously thatpermit a relatively simple deconstruction of the elastic and wavepropagation behavior in terms of a small number of fracture parameters(whenever this is appropriate, as is certainly the case for small crackdensities). Then, the quantitative effects of fluids on thesecrack-influence parameters are shown to be directly related to Skempton scoefficient B of undrained poroelasticity (where B typically ranges from0 to 1). In particular, the rigorous result obtained for the low crackdensity limit is that the crack-influence parameters are multiplied by afactor (1 ? B) for undrained systems. It is also shown how fractureanisotropy affects Rayleigh wave speed, and …
Date: May 14, 2007
Creator: Berryman, J.G.
Object Type: Article
System: The UNT Digital Library
Homeland Security: Intelligence Support (open access)

Homeland Security: Intelligence Support

Legislation establishing a Department of Homeland Security includes provisions for an information analysis element within the new department. This report examines the information analysis function and the sharing of information among federal agencies but does not address provisions in the proposed legislation governing the sharing of intelligence with state and local officials.
Date: May 14, 2003
Creator: Best, Richard A., Jr.
Object Type: Report
System: The UNT Digital Library
CP Violation in B Decays (open access)

CP Violation in B Decays

None
Date: May 14, 2007
Creator: Biasini, M. & U., /Perugia
Object Type: Article
System: The UNT Digital Library
The United Arab Emirates Nuclear Program and Proposed U.S. Nuclear Cooperation (open access)

The United Arab Emirates Nuclear Program and Proposed U.S. Nuclear Cooperation

This report provides background information on the UAE nuclear program, reviews developments to date, analyzes proposed nuclear cooperation with the United States, and discusses relevant legislative proposals and options.
Date: May 14, 2009
Creator: Blanchard, Christopher M. & Kerr, Paul K.
Object Type: Report
System: The UNT Digital Library
PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ON SPIN PHYSICS AT RHIC IN YEAR-1 AND BEYOND. (open access)

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ON SPIN PHYSICS AT RHIC IN YEAR-1 AND BEYOND.

The much anticipated RHIC spin physics program will commence this fall when the first physics run with colliding beams of polarized protons is expected. More specifically, the planned year-1 RHIC-Spin measurements are (1) the double-spin asymmetry A{sub LL}{sup {pi}} in production of pions by collisions of longitudinally polarized protons (in order to obtain first information on the proton's spin-dependent gluon density, {Delta}g); (2) the transverse single-spin asymmetry A{sub N}{sup {pi}} for pion production. These two reactions provided part of the motivation for our workshop. On the first day there were informative talks on the specific plans of STAR (by Rakness) and PHENIX (by Goto) for the polarized run of Year-1. Some of the theoretical questions related to the double-spin asymmetry A{sub LL}{sup {pi}} were discussed on the first day by Vogelsang and Kretzer, which centered mostly around the questions of how well the unpolarized fragmentation functions are known, the need for next-to-leading order calculations, and on how sensitive the asymmetry is to the possible {Delta}g distributions. Vetterli presented HERMES measurements of fragmentation functions, which overlap in Q{sup 2} with the future lower-p{sub T} measurements at RHIC.
Date: May 14, 2001
Creator: Bland, L.; Boer, D.; Saito, N. & Vogelsang, W.
Object Type: Report
System: The UNT Digital Library
Homeland Security: Establishment and Implementation of Northern Command (open access)

Homeland Security: Establishment and Implementation of Northern Command

Report on the Department of Defense's (DoD) establishment of U.S. Northern Command (NORTHCOM) advancements in fighting terrorism, as well as the issues of NORTHCOM's relationship with other agencies within the DoD.
Date: May 14, 2003
Creator: Bolkcom, Christopher; DeSerisy, Lloyd & Kapp, Lawrence
Object Type: Report
System: The UNT Digital Library
Pulling of 3 mm diameter AlSb rods by micro-pulling down method (open access)

Pulling of 3 mm diameter AlSb rods by micro-pulling down method

We designed and supplied special crucibles for AlSb material. Thermal insulation and limitation of Sb losses were our first work. The protection of the growth environment was also one of our priority to avoid any pollution of the Fibercryst {mu}PD facility. When this work was achieved, the next step was the calibration of the heating power for these new crucibles. Then, it was the definition of single crystal growth conditions that oriented our research. Following our proposal, many growths attempts were performed. We started from Al & Sb pure powder or from LBNL AlSb crystal as expected. We used different crucibles and different seeds.
Date: May 14, 2009
Creator: Bourret-Courchesne, Edith & Perrodin, Didier
Object Type: Report
System: The UNT Digital Library
Homeland Security: The Department of Defense's Role (open access)

Homeland Security: The Department of Defense's Role

This report addresses the Department of Defense's role of Homeland Security.
Date: May 14, 2003
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
Iraq: U.S. Military Operations (open access)

Iraq: U.S. Military Operations

None
Date: May 14, 2003
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library