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Improved Measurement of CP Violation in Neutral BDecays to \ccbar s (open access)

Improved Measurement of CP Violation in Neutral BDecays to \ccbar s

The authors present updated measurements of time-dependent CP asymmetries in fully-reconstructed neutral B decays to several CP eigenstates containing a charmonium meson. The measurements use a data sample of (383 {+-} 4) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II B factory. They determine sin2{beta} = 0.714 {+-} 0.032(stat) {+-} 0.018(syst) and |{lambda}| = 0.952 {+-} 0.022(stat) {+-} 0.017(syst).
Date: April 25, 2007
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Decay Amplitudes of B to (ccbar) K^* withan Angular Analysis, for (ccbar)=J/Psi,Psi(2S) and Chi_c1 (open access)

Measurement of Decay Amplitudes of B to (ccbar) K^* withan Angular Analysis, for (ccbar)=J/Psi,Psi(2S) and Chi_c1

The authors perform the first three-dimensional measurement of the amplitudes of B {yields} {psi}(2S)K* and B {yields} {chi}{sub c1}K* decays and update the previous measurement B {yields} J/{psi}K*. They use a data sample collected with the BABAR detector at the PEP-II storage ring, corresponding to 232 million B{bar B} pairs. The longitudinal polarization of decays involving a J{sup PC} = 1{sup ++} {chi}{sub c1} meson is found to be larger than that with a 1{sup --} J/{psi} or {psi}(2S) meson. No direct CP-violating charge asymmetry is observed.
Date: April 25, 2007
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Absolute Branching Fraction of D0 to K- pi+ (open access)

Measurement of the Absolute Branching Fraction of D0 to K- pi+

The authors measure the absolute branching fraction for D{sup 0} {yields} K{sup -} {pi}{sup +} using partial reconstruction of {bar B}{sup 0} {yields} D*{sup +}X{ell}{sup -}{bar {nu}}{sub {ell}} decays, in which only the charged lepton and the pion from the decay D*{sup +} {yields} D{sup 0}{pi}{sup +} are used. Based on a data sample of 230 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, they obtain {Beta}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = (4.007 {+-} 0.037 {+-} 0.070)%, where the first error is statistical and the second error is systematic.
Date: April 25, 2007
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
Object Type: Article
System: The UNT Digital Library
Fabrication and In Vitro Deployment of a Laser-Activated Shape Memory Polymer Vascular Stent (open access)

Fabrication and In Vitro Deployment of a Laser-Activated Shape Memory Polymer Vascular Stent

Vascular stents are small tubular scaffolds used in the treatment of arterial stenosis (narrowing of the vessel). Most vascular stents are metallic and are deployed either by balloon expansion or by self-expansion. A shape memory polymer (SMP) stent may enhance flexibility, compliance, and drug elution compared to its current metallic counterparts. The purpose of this study was to describe the fabrication of a laser-activated SMP stent and demonstrate photothermal expansion of the stent in an in vitro artery model. A novel SMP stent was fabricated from thermoplastic polyurethane. A solid SMP tube formed by dip coating a stainless steel pin was laser-etched to create the mesh pattern of the finished stent. The stent was crimped over a fiber-optic cylindrical light diffuser coupled to an infrared diode laser. Photothermal actuation of the stent was performed in a water-filled mock artery. At a physiological flow rate, the stent did not fully expand at the maximum laser power (8.6 W) due to convective cooling. However, under zero flow, simulating the technique of endovascular flow occlusion, complete laser actuation was achieved in the mock artery at a laser power of {approx}8 W. We have shown the design and fabrication of an SMP stent and …
Date: April 25, 2007
Creator: Baer, G. M.; Small, W., IV; Wilson, T. S.; Benett, W. J.; Matthews, D. L.; Hartman, J. et al.
Object Type: Article
System: The UNT Digital Library
On-Shell Methods in Perturbative QCD (open access)

On-Shell Methods in Perturbative QCD

We review on-shell methods for computing multi-parton scattering amplitudes in perturbative QCD, utilizing their unitarity and factorization properties. We focus on aspects which are useful for the construction of one-loop amplitudes needed for phenomenological studies at the Large Hadron Collider.
Date: April 25, 2007
Creator: Bern, Zvi; Dixon, Lance J. & Kosower, David A.
Object Type: Article
System: The UNT Digital Library
The Colony Courier-Leader (The Colony, Tex.), Vol. 26, No. 12, Ed. 1 Wednesday, April 25, 2007 (open access)

The Colony Courier-Leader (The Colony, Tex.), Vol. 26, No. 12, Ed. 1 Wednesday, April 25, 2007

Weekly newspaper from The Colony, Texas that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Bick, Jack & Crimmins, Blaine
Object Type: Newspaper
System: The Portal to Texas History
The Goldthwaite Eagle (Goldthwaite, Tex.), Vol. 112, No. 41, Ed. 1 Wednesday, April 25, 2007 (open access)

The Goldthwaite Eagle (Goldthwaite, Tex.), Vol. 112, No. 41, Ed. 1 Wednesday, April 25, 2007

Weekly newspaper from Goldthwaite, Texas that includes local, state, and national news along with extensive advertising.
Date: April 25, 2007
Creator: Bridges, Steven W.
Object Type: Newspaper
System: The Portal to Texas History
Perry Daily Journal (Perry, Okla.), Vol. 115, No. 81, Ed. 1 Wednesday, April 25, 2007 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 115, No. 81, Ed. 1 Wednesday, April 25, 2007

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, April 25, 2007 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, April 25, 2007

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 108, No. 334, Ed. 1 Wednesday, April 25, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 108, No. 334, Ed. 1 Wednesday, April 25, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Pair Creation at Large Inherent Angles (open access)

Pair Creation at Large Inherent Angles

In the next-generation linear colliders, the low-energy e{sup +}e{sup -} pairs created during the collision of high-energy e{sup +}e{sup -} beams would cause potential deleterious background problems to the detectors. At low collider energies, the pairs are made essentially by the incoherent process, where the pair is created by the interaction of beamstrahlung photons on the individual particles in the oncoming beam. This problem was first identified by Zolotarev, et al[1]. At energies where the beamstrahlung parameter {Upsilon} lies approximately in the range 0.6 {approx}< {Upsilon} {approx}< 100, pair creation from the beamstrahlung photons is dominated by a coherent process, first noted by Chen[2]. The seriousness of this pair creation problem lies in the transverse momenta that the pair particles carry when leaving the interaction point (IP) with large angles. One source of transverse momentum is from the kick by the field of the oncoming beam which results in an outcoming angle {theta} {proportional_to} 1/{radical}x, where x is the fractional energy of the particle relative to the initial beam particle energy[2,3]. As was shown in Ref. 131, there in fact exists an energy threshold for the coherent pairs, where x{sub th} {approx}> 1/2{Upsilon}. Thus within a tolerable exiting angle, there …
Date: April 25, 2007
Creator: Chen, P.; Tauchi, T. & Schroeder, D.V.
Object Type: Article
System: The UNT Digital Library
Gamma-ray Source Stacking Analysis at Low Galactic Latitude (open access)

Gamma-ray Source Stacking Analysis at Low Galactic Latitude

We studied the problematic of uncertainties in the diffuse gamma radiation apparent in stacking analysis of EGRET data at low Galactic latitudes. Subsequently, we co-added maps of counts, exposure and diffuse background, and residuals, in varying numbers for different sub-categories of putatively and known source populations (like PSRs). Finally we tested for gamma-ray excess emission in those maps and attempt to quantify the systematic biases in such approach. Such kind of an analysis will help the classification processes of sources and source populations in the GLAST era.
Date: April 25, 2007
Creator: Cillis, Analia N.; Reimer, Olaf & Torres, Diego F.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 149, Ed. 1 Wednesday, April 25, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 149, Ed. 1 Wednesday, April 25, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Localized Electron States Near a Metal-SemiconductorNanocontact (open access)

Localized Electron States Near a Metal-SemiconductorNanocontact

The electronic structure of nanowires in contact withmetallic electrodes of experimentally relevant sizes is calculated byincorporating the electrostatic polarization potential into the atomisticsingle particle Schrodinger equation. We show that the presence of anelectrode produces localized electron/hole states near the electrode, aphenomenon only exhibited in nanostructures and overlooked in the past.This phenomenon will have profound implications on electron transport insuch nanosystems. We calculate several electrode/nanowire geometries,with varying contact depths and nanowire radii. We demonstrate the changein the band gap of up to 0.5 eV in 3 nm diameter CdSe nanowires andcalculate the magnitude of the applied electric field necessary toovercome the localization.
Date: April 25, 2007
Creator: Demchenko, Denis O. & Wang, Lin-Wang
Object Type: Article
System: The UNT Digital Library
The Silsbee Bee (Silsbee, Tex.), Vol. [91], No. [17], Ed. 1 Wednesday, April 25, 2007 (open access)

The Silsbee Bee (Silsbee, Tex.), Vol. [91], No. [17], Ed. 1 Wednesday, April 25, 2007

Weekly newspaper from Silsbee, Texas that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Dickert, Gerry
Object Type: Newspaper
System: The Portal to Texas History
Critical Chemical-Mechanical Couplings that Define Permeability Modifications in Pressure-Sensitive Rock Fractures (open access)

Critical Chemical-Mechanical Couplings that Define Permeability Modifications in Pressure-Sensitive Rock Fractures

This work examined and quantified processes controlling changes in the transport characteristics of natural fractures, subjected to coupled thermal-mechanical-chemical (TMC) effects. Specifically, it examined the effects of mineral dissolution and precipitation mediated by mechanical effects, using laboratory through-flow experiments concurrently imaged by X-ray CT. These were conducted on natural and artificial fractures in cores using water as the permeant. Fluid and mineral mass balances are recorded and are correlated with in-sample saturation, porosity and fracture aperture maps, acquired in real-time by X-ray CT-imaging at a maximum spatial resolution of 15-50 microns per pixel. Post-test, the samples were resin-impregnated, thin-sectioned, and examined by microscopy to define the characteristics of dissolution and precipitation. The test-concurrent X-ray imaging, mass balances, and measurements of permeability, together with the post-test microscopy, were used to define dissolution/precipitation processes, and to constrain process-based models. These models define and quantify key processes of pressure solution, free-face dissolution, and shear-dilation, and the influence of temperature, stress level, and chemistry on the rate of dissolution, its distribution in space and time, and its influence on the mechanical and transport properties of the fracture.
Date: April 25, 2007
Creator: Elsworth, Derek; Grader, Abraham & Brantley, Susan
Object Type: Report
System: The UNT Digital Library
The Wylie News (Wylie, Tex.), Vol. 59, No. 49, Ed. 1 Wednesday, April 25, 2007 (open access)

The Wylie News (Wylie, Tex.), Vol. 59, No. 49, Ed. 1 Wednesday, April 25, 2007

Weekly newspaper from Wylie, Texas that includes local, state and national news along with advertising.
Date: April 25, 2007
Creator: Engbrock, Chad B.
Object Type: Newspaper
System: The Portal to Texas History
Financial Services Regulatory Relief: Implementation and Reintroduced Provisions in the 110th Congress (open access)

Financial Services Regulatory Relief: Implementation and Reintroduced Provisions in the 110th Congress

None
Date: April 25, 2007
Creator: Eubanks, Walter W.
Object Type: Report
System: The UNT Digital Library
Electrochemical Studies of Passive Film Stability on Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 Amorphous Metal in Seawater at 90oCElectrochemical Studies of Passive Film Stability on Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 Amorphous Metal in Seawater at 9 (open access)

Electrochemical Studies of Passive Film Stability on Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 Amorphous Metal in Seawater at 90oCElectrochemical Studies of Passive Film Stability on Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 Amorphous Metal in Seawater at 9

An iron-based amorphous metal, Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4} (SAM2X5), with very good corrosion resistance was developed. This material was prepared as a melt-spun ribbon, as well as gas atomized powder and a thermal-spray coating. During electrochemical testing in several environments, including seawater at 90 C, the passive film stability was found to be comparable to that of high-performance nickel-based alloys, and superior to that of stainless steels, based on electrochemical measurements of the passive film breakdown potential and general corrosion rates. This material also performed very well in standard salt fog tests. Chromium (Cr), molybdenum (Mo) and tungsten (W) provided corrosion resistance, and boron (B) enabled glass formation. The high boron content of this particular amorphous metal made it an effective neutron absorber, and suitable for criticality control applications. This material and its parent alloy maintained corrosion resistance up to the glass transition temperature, and remained in the amorphous state during exposure to relatively high neutron doses.
Date: April 25, 2007
Creator: Farmer, J C; Haslam, J; Day, S D; Lian, T; Saw, C K; Hailey, P D et al.
Object Type: Report
System: The UNT Digital Library
Electrochemical Studies of Passive Film Stability on Fe48Mo14Cr15Y2C15B Amorphous Metal in Seawater at 90oC and 5M CaCl2 at 105oC (open access)

Electrochemical Studies of Passive Film Stability on Fe48Mo14Cr15Y2C15B Amorphous Metal in Seawater at 90oC and 5M CaCl2 at 105oC

Several Fe-based amorphous metal formulations have been identified that appear to have corrosion resistance comparable to, or better than that of Ni-based Alloy C-22 (UNS N06022), based on measurements of breakdown potential and corrosion rate in seawater. Both chromium (Cr) and molybdenum (Mo) provide corrosion resistance, boron (B) enables glass formation, and rare earths such as yttrium (Y) lower critical cooling rate (CCR). Amorphous Fe{sub 48.0}Cr{sub 15.0}Mo{sub 14.0}B{sub 6.0}C{sub 15.0}Y{sub 2.0} (SAM1651) has a low critical cooling rate (CCR) of less than 80 Kelvin per second, due to the addition of yttrium. The low CCR enables it to be rendered as a completely amorphous material in practical materials processes. While the yttrium enables a low CCR to be achieved, it makes the material relatively difficult to atomize, due to increases in melt viscosity. Consequently, the powders produced thus far have had irregular shape, which had made pneumatic conveyance during thermal spray deposition difficult.
Date: April 25, 2007
Creator: Farmer, J. C.; Day, S. D.; Lian, T.; Saw, C. K.; Hailey, P. D.; Blue, C. A. et al.
Object Type: Report
System: The UNT Digital Library
Initial Report on the Development of a Monte Carlo-Markov Chain Joint Inversion Approach for Geothermal Exploration (open access)

Initial Report on the Development of a Monte Carlo-Markov Chain Joint Inversion Approach for Geothermal Exploration

Geothermal exploration and subsequent characterization of potential resources typically employ a variety of geophysical, geologic and geochemical techniques. However, since the data collected by each technique provide information directly on only one or a very limited set of the many physical parameters that characterize a geothermal system, no single method can be used to describe the system in its entirety. Presently, the usual approach to analyzing disparate data streams for geothermal applications is to invert (or forward model) each data set separately and then combine or compare the resulting models, for the most part in a more or less ad hoc manner. However, while each inversion may yield a model that fits the individual data set, the models are usually inconsistent with each other to some degree. This reflects uncertainties arising from the inevitable fact that geophysical and other exploration data in general are to some extent noisy, incomplete, and of limited sensitivity and resolution, and so yield non-unique results. The purpose of the project described here is to integrate the different model constraints provided by disparate geophysical, geological and geochemical data in a rigorous and consistent manner by formal joint inversion. The objective is to improve the fidelity of …
Date: April 25, 2007
Creator: Foxall, W; Ramirez, A; Carlson, S; Dyer, K & Sun, Y
Object Type: Report
System: The UNT Digital Library
Technical Equivalency Documentation for a Newly Aquired Alpha Spectroscopy System (open access)

Technical Equivalency Documentation for a Newly Aquired Alpha Spectroscopy System

The response of a recently acquired Canberra{trademark} Alpha Analyst 'Blue' system (Chamber Number's 173-208) used by the Hazards Control, Radiation Safety Section, WBC/Spectroscopy Team has been studied with respect to an existing Canberra system. The existing Canberra system consists of thirty Alpha Analyst dual chambers Model XXXX comprising a total of sixty detectors (Chambers Number's 101-124 and 137-172). The existing chambers were previously compared to an older system consisting of thirty-six Model 7401 alpha spectrometry chambers (Chamber Number's 1-36) Chambers 101-124 and 137-172 are DOELAP accredited. The older system was previously DOELAP accredited for the routine Alpha Spectroscopy program used in LLNL's in vitro bioassay program. The newly acquired Alpha Analyst system operates on a network with software that controls and performs analysis of the current Alpha Analyst system (Chamber Number's 101-124 and 137-172). This exact same software is used for the current system and the newly acquired system and is DOELAP accredited. This document compares results from the existing Alpha System with the newer Alpha Analyst system.
Date: April 25, 2007
Creator: Hickman, D P; Fisher, S K; Hann, P R & Hume, R
Object Type: Report
System: The UNT Digital Library
Chemical Bonding and Structural Information of Black Carbon Reference Materials and Individual Carbonaceous Atmospheric Aerosols (open access)

Chemical Bonding and Structural Information of Black Carbon Reference Materials and Individual Carbonaceous Atmospheric Aerosols

The carbon-to-oxygen ratios and graphitic nature of a rangeof black carbon standard reference materials (BC SRMs), high molecularmass humic-like substances (HULIS) and atmospheric particles are examinedusing scanning transmission X-ray microscopy (STXM) coupled with nearedge X-ray absorption fine structure (NEXAFS) spectroscopy. UsingSTXM/NEXAFS, individual particles with diameter>100 nm are studied,thus the diversity of atmospheric particles collected during a variety offield missions is assessed. Applying a semi-quantitative peak fittingmethod to the NEXAFS spectra enables a comparison of BC SRMs and HULIS toparticles originating from anthropogenic combustion and biomass burns,thus allowing determination of the suitability of these materials forrepresenting atmospheric particles. Anthropogenic combustion and biomassburn particles can be distinguished from one another using both chemicalbonding and structural ordering information. While anthropogeniccombustion particles are characterized by a high proportion ofaromatic-C, the presence of benzoquinone and are highly structurallyordered, biomass burn particles exhibit lower structural ordering, asmaller proportion of aromatic-C and contain a much higher proportion ofoxygenated functional groups.
Date: April 25, 2007
Creator: Hopkins, Rebecca J.; Tivanski, Alexei V.; Marten, Bryan D. & Gilles, Mary K.
Object Type: Article
System: The UNT Digital Library
Mannford Eagle (Mannford, Okla.), Vol. 25, No. 54, Ed. 1 Wednesday, April 25, 2007 (open access)

Mannford Eagle (Mannford, Okla.), Vol. 25, No. 54, Ed. 1 Wednesday, April 25, 2007

Weekly newspaper from Mannford, Oklahoma that includes local, state, and national news along with advertising.
Date: April 25, 2007
Creator: Hughes, Dustin
Object Type: Newspaper
System: The Gateway to Oklahoma History