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Longitudinal double-spin asymmetry and cross section for inclusivejet production in polarized proton collisions at sqrt(s) = 200 GeV (open access)

Longitudinal double-spin asymmetry and cross section for inclusivejet production in polarized proton collisions at sqrt(s) = 200 GeV

We report a measurement of the longitudinal double-spinasymmetry A_LL and the differential cross section for inclusivemidrapidity jet production in polarized proton collisions at sqrt(s)=200GeV. The cross section data cover transverse momenta 5<pT<50GeV/c and agree with next-to-leading order perturbative QCD evaluations.The A_LL data cover 5<pT<17 GeV/c and disfavor at 98 percentC.L. maximal positive gluon polarization in the polarizednucleon.
Date: August 10, 2006
Creator: Abelev, B. I.; Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Object Type: Article
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 32, Ed. 1 Thursday, August 10, 2006 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 32, Ed. 1 Thursday, August 10, 2006

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: August 10, 2006
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
The Relation Between Accretion Rate And Jet Power in X-Ray Luminous Elliptical Galaxies (open access)

The Relation Between Accretion Rate And Jet Power in X-Ray Luminous Elliptical Galaxies

Using Chandra X-ray observations of nine nearby, X-ray luminous elliptical galaxies with good optical velocity dispersion measurements, we show that a tight correlation exists between the Bondi accretion rates calculated from the observed gas temperature and density profiles and estimated black hole masses, and the power emerging from these systems in relativistic jets. The jet powers, which are inferred from the energies and timescales required to inflate cavities observed in the surrounding X-ray emitting gas, can be related to the accretion rates using a power law model of the form log (P{sub Bondi}/10{sup 43} erg s{sup -1}) = A + B log (P{sub jet}/10{sup 43} erg s{sup -1}), with A = 0.62 {+-} 0.15 and B = 0.77 {+-} 0.18. Our results show that a significant fraction of the energy associated with the rest mass of material entering the Bondi accretion radius (2.4{sub -0.7}{sup +1.0} per cent, for P{sub jet} = 10{sup 43} erg s{sup -1}) eventually emerges in the relativistic jets. Our results have significant implications for studies of accretion, jet formation and galaxy formation. The observed tight correlation suggests that the Bondi formulae provide a reasonable description of the accretion process in these systems, despite the likely presence …
Date: March 10, 2006
Creator: Allen, Steven W.; Dunn, R. J. H.; Fabian, A. C.; Taylor, G. B. & Reynolds, C. S.
Object Type: Report
System: The UNT Digital Library
Environmental Monitoring Plan (open access)

Environmental Monitoring Plan

Environmental monitoring personnel from Lawrence Livermore National Laboratory (LLNL) prepared this ''Environmental Monitoring Plan'' (EMP) to meet the requirements in the U.S. Department of Energy (DOE) ''Environmental Regulatory Guide for Radiological Effluent Monitoring and Environmental Surveillance'' (DOE 1991) and applicable portions of DOE Orders 5400.1 and 5400.5 (see WSS B93 and B94 in Appendix B). ''Environmental Regulatory Guide for Radiological Effluent Monitoring and Environmental Surveillance'' is followed as a best management practice; under Work Smart Standards, LLNL complies with portions of DOE Orders 5400.1 and 5400.5 as shown in Appendix B. This document is a revision of the May 1999 EMP (Tate et al. 1999) and is current as of March 1, 2002. LLNL is one of the nation's premier applied-science national security laboratories. Its primary mission is to ensure that the nation's nuclear weapons remain safe, secure, and reliable, and to prevent the spread and use of nuclear weapons worldwide. LLNL's programs in advanced technologies, energy, environment, biosciences, and basic science apply LLNL's unique capabilities and enhance the competencies needed for this national security mission. LLNL's mission also involves working with industrial and academic partners to increase national competitiveness and improve science education. LLNL's mission is dynamic and has …
Date: January 10, 2006
Creator: Althouse, P. E.; Biermann, A.; Brigdon, S. L.; Brown, R. A.; Campbell, C. G.; Christofferson, E. et al.
Object Type: Report
System: The UNT Digital Library
Smoothing of ultrathin silver films by transition metalseeding (open access)

Smoothing of ultrathin silver films by transition metalseeding

The nucleation and coalescence of silver islands on coated glass was investigated by in-situ measurements of the sheet resistance. Sub-monolayer amounts of transition metals (Nb, Ti, Ni, Cr, Zr, Ta, and Mo) were deposited prior to the deposition of silver. It was found that some, but not all, of the transition metals lead to coalescence of silver at nominally thinner films with smoother topology. The smoothing effect of the transition metal at sub-monolayer thickness can be explained by a thermodynamic model of surface energies.
Date: February 10, 2006
Creator: Anders, Andre; Byon, Eungsun; Kim, Dong-Ho; Fukuda, Kentaro & Lim,Sunnie H.N.
Object Type: Article
System: The UNT Digital Library
Enabling Science and Technology Computation Directorate 2005 Annual Report (open access)

Enabling Science and Technology Computation Directorate 2005 Annual Report

None
Date: March 10, 2006
Creator: Anderson, S R; Zosel, M E & Miller, M C
Object Type: Report
System: The UNT Digital Library
Cleanup Verification Package for the 618-8 Burial Ground (open access)

Cleanup Verification Package for the 618-8 Burial Ground

This cleanup verification package documents completion of remedial action for the 618-8 Burial Ground, also referred to as the Solid Waste Burial Ground No. 8, 318-8, and the Early Solid Waste Burial Ground. During its period of operation, the 618-8 site is speculated to have been used to bury uranium-contaminated waste derived from fuel manufacturing, and construction debris from the remodeling of the 313 Building.
Date: August 10, 2006
Creator: Appel, M. J.
Object Type: Report
System: The UNT Digital Library
Power Corrections in Charmless Nonleptonic B Decays: Annihilationis Factorizable and Real (open access)

Power Corrections in Charmless Nonleptonic B Decays: Annihilationis Factorizable and Real

We classify {Lambda}{sub QCD}/m{sub b} power corrections to nonleptonic B {yields} M{sub 1}M{sub 2} decays, where M{sub 1,2} are charmless non-isosinglet mesons. Using recent developments in soft-collinear effective theory, we prove that the leading contributions to annihilation amplitudes of order {alpha}{sub s}(m{sub b}) {Lambda}{sub QCD}/m{sub b} are real. The leading annihilation amplitudes depend on twist-2 and the twist-3 three parton distributions. A complex nonperturbative parameter from annihilation first appears at {Omega}[{alpha}{sub s}{sup 2}({radical}{Lambda}m{sub b}){Lambda}{sub QCD}/m{sub b}]. 'Chirally enhanced' contributions are also factorizable and real at lowest order. Thus, incalculable strong phases are suppressed in annihilation amplitudes, unless the {alpha}{sub s}({radical}{Lambda}m{sub b}) expansion breaks down. Modeling the distribution functions, we find that (11 {+-} 9)% and (15 {+-} 11)% of the absolute values of the measured {bar B}{sup 0} {yields} K{sup -}{pi}{sup +} and B{sup -} {yields} K{sup -}K{sup 0} penguin amplitudes come from annihilation. This is consistent with the expected size of power corrections.
Date: October 10, 2006
Creator: Arnesen, Christian M.; Ligeti, Zoltan; Rothstein, Ira Z. & Stewart, Iain W.
Object Type: Article
System: The UNT Digital Library
Discovering Chiral Higgsinos at the LHC (open access)

Discovering Chiral Higgsinos at the LHC

The concept of chirality is extended to the Minimal Supersymmetric Standard Model (MSSM) and the {micro} term is forbidden by a gauged U(1){prime} symmetry. R-parity automatically emerges after symmetry breaking, suppressing proton decay and protecting the LSP. Exotics charged under the SM pose a challenge to traditional SU(5) unification, but unification is still implemented in deconstructed GUTs. Because of the multitude of additional states to the MSSM, the Z{prime} has a large width, and the SM background, neglected in previous theoretical studies, becomes important for Z{prime} discovery. As a result, the LHC reach is reduced from 3.2 TeV, for a Z{prime} with SM decays, to 1.5 TeV, when additional decay channels are included. This model also predicts possibly long-lived colored and electroweak exotics.
Date: November 10, 2006
Creator: Arvanitaki, Asimina & /Stanford U., ITP /SLAC
Object Type: Report
System: The UNT Digital Library

Renewable Energy: Poised to Realize Long-Term Potential

None
Date: June 10, 2006
Creator: Arvizu, D.
Object Type: Presentation
System: The UNT Digital Library
Documentation of Naval Reactors Papers and Presentations for the Space Technology and International Forum (STAIF) 2006 (open access)

Documentation of Naval Reactors Papers and Presentations for the Space Technology and International Forum (STAIF) 2006

None
Date: April 10, 2006
Creator: Ashcroft, JM
Object Type: Report
System: The UNT Digital Library
MODIFIED BOROHYDRIDES FOR REVERSIBLE HYDROGEN STORAGE (open access)

MODIFIED BOROHYDRIDES FOR REVERSIBLE HYDROGEN STORAGE

This paper reports the results in the effort to destabilize lithium borohydride for reversible hydrogen storage. A number of metals, metal hydrides, metal chlorides and complex hydrides were selected and evaluated as the destabilization agents for reducing dehydriding temperature and generating dehydriding-rehydriding reversibility. It is found that some additives are effective. The Raman spectroscopic analysis shows the change of B-H binding nature.
Date: May 10, 2006
Creator: Au, Ming
Object Type: Article
System: The UNT Digital Library
Branching Fraction Limits for B0 Decays to eta' eta, eta' pi0 and eta pi0 (open access)

Branching Fraction Limits for B0 Decays to eta' eta, eta' pi0 and eta pi0

We describe searches for decays to two-body charmless final states {eta}'{eta}, {eta}'{pi}{sup 0} and {eta}{pi}{sup 0} of B{sup 0} mesons produced in e{sup +}e{sup -} annihilation. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 232 million produced B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup 0} {yields} {eta}'{eta}) = 0.2{sub -0.5}{sup +0.7} {+-} 0.4 (&lt; 1.7), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.6{sub -0.4}{sup +0.5} {+-} 0.1 (&lt; 1.3), and {Beta}(B{sup 0} {yields} {eta}'{pi}{sup 0}) = 0.8{sub -0.6}{sup +0.8} {+-} 0.1 (&lt; 2.1). The first error quoted is statistical and the second systematic.
Date: March 10, 2006
Creator: Aubert, B.
Object Type: Report
System: The UNT Digital Library
Measurement of B0bar -> D(*)0 K(*)0bar BranchingFractions (open access)

Measurement of B0bar -> D(*)0 K(*)0bar BranchingFractions

The authors present a study of the decays {bar B}{sup 0} {yields} D{sup (*)0}{bar K}{sup (*)0} using a sample of 226 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. They report evidence for the decay of B{sup 0} and {bar B}{sup 0} mesons to the D*{sup 0}K{sub S}{sup 0} final state with an average branching fraction {Beta}({bar B}{sup 0} {yields} D*{sup 0} {bar K}{sup 0}) {triple_bond} {Beta}({bar B}{sup 0} {yields} D*{sup 0} {bar K}{sup 0}) + {Beta}(B{sup 0} {yields} D*{sup 0}K{sup 0})/2 = (3.6 {+-} 1.2 {+-} 0.3) x 10{sup -5}.
Date: April 10, 2006
Creator: Aubert, B.
Object Type: Report
System: The UNT Digital Library
Measurement of the B- -> D0K*- Branching Fraction (open access)

Measurement of the B- -> D0K*- Branching Fraction

From a sample of 232 million {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II B Factory in 1999-2004, they measure the B{sup -} {yields} D{sup 0} K*{sup -}(892) decay branching fraction using events where the K*{sup -} is reconstructed in the K{sub S}{sup 0}{pi}{sup -} mode and the D{sup 0} in the K{sup -}{pi}{sup +}, K{sup -}{pi}{sup +}{pi}{sup 0}, and K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -} channels: {Beta}(B{sup -} {yields} D{sup 0}K*{sup -}(892)) = (5.29 {+-} 0.30 (stat) {+-} 0.34 (syst)) x 10{sup -4}.
Date: April 10, 2006
Creator: Aubert, B.
Object Type: Report
System: The UNT Digital Library
Search for the Decay B^0 -> a^\pm_1 \rho^\mp (open access)

Search for the Decay B^0 -> a^\pm_1 \rho^\mp

The authors present a search for the rare B-meson decay B{sup 0} {yields} {alpha}{sub 1}{sup {+-}}{rho}{sup {-+}} with {alpha}{sub 1}{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup {+-}}. We use (110 {+-} 1.2) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEp-II asymmetric-energy B Factory at SLAC. They obtain an upper limit of 30 x 10{sup -6} (90% C.L.) for the branching fraction product {Beta}(B{sup 0} {yields} {alpha}{sub 1}{sup {+-}}{rho}{sup {-+}}) {Beta}({alpha}{sub 1}{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup {+-}}), where they assume that the {alpha}{sub 1}{sup {+-}} decays exclusively to {rho}{sup 0}{pi}{sup {+-}}.
Date: May 10, 2006
Creator: Aubert, B.
Object Type: Report
System: The UNT Digital Library
Search for the Decay $\tau^- \rightarrow 3\pi^- 2\pi^+2\pi^0 \nu_\tau$ (open access)

Search for the Decay $\tau^- \rightarrow 3\pi^- 2\pi^+2\pi^0 \nu_\tau$

A search for the decay of the {tau} lepton to five charged and two neutral pions is performed using data collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider. The analysis uses 232 fb{sup -1} of data at center-of-mass energies on or near the {Upsilon}(4S) resonance. We observe 10 events with an expected background of 6.5{sub -1.4}{sup +2.0} events. In the absence of a signal, we set the limit on the branching ratio {Beta}({tau}{sup -} {yields} 3{pi}{sup -}2{pi}{sup +}2{pi}{sup 0}{nu}{sub {tau}}) &lt; 3.4 x 10{sup -6} at the 90% confidence level. This is a significant improvement over the previously established limit. In addition, we search for the decay mode {tau}{sup -} {yields} 2{omega}{pi}{sup -}{nu}{sub {tau}}. We observe 1 event with an expected background of 0.4{sub -0.4}{sup +1.0} events and calculate the upper limit {Beta}({tau}{sup -} {yields} 2{omega}{pi}{sup -}{nu}{sub {tau}}) &lt; 5.4 x 10{sup -7} at the 90% confidence level. This is the first upper limit for this mode.
Date: April 10, 2006
Creator: Aubert, B.
Object Type: Report
System: The UNT Digital Library
2006 Annual Report Summer Research Institute Interfacial and Condensed Phase Chemical Physics (open access)

2006 Annual Report Summer Research Institute Interfacial and Condensed Phase Chemical Physics

The Pacific Northwest National Laboratory (PNNL) hosted its third annual Summer Research Institute in Interfacial and Condensed Phase Chemical Physics from May through September 2006. During this period, twenty PNNL scientists hosted twenty-seven scientists from twenty-five different universities. Of the twenty-seven participants, one was a graduating senior; twenty-one were graduate students; one was a postdoctoral fellow; and four were university faculty members.
Date: November 10, 2006
Creator: Avery, Nikki B. & Barlow, Stephan E.
Object Type: Report
System: The UNT Digital Library

U.S. and Russian Cooperation on the Russian Federal Information System (FIS)

None
Date: April 10, 2006
Creator: Babcock, Rusty
Object Type: Presentation
System: The UNT Digital Library
Optimization of Beam Injection into the First Accelerating Module at TTF With Cavity Dipole Mode Signals (open access)

Optimization of Beam Injection into the First Accelerating Module at TTF With Cavity Dipole Mode Signals

The TESLA Test Facility (TTF) is a user facility for intense VUV-FEL light. The facility is densely equipped with diagnostics, essential in obtaining the necessary beam parameters, in particular the low emittance. However there is no dedicated component for alignment of the beam in the accelerating modules, each containing eight superconducting cavities. Large beam offsets can lead to an increase of the beam emittance. The centering of the beam in these modules is therefore important, mostly at the low energy end. A misalignment of the first TTF module with respect to the gun axis has already been observed using cavity dipole modes. This paper presents the experimental results of the optimization of the beam injection into the first module, based on the monitoring of dipole modes through the couplers installed for wakefield damping. For this we use a spectrum analyzer together with a multiplexer. By scanning the beam position and tilt with two pairs of steerers, we can find the trajectory which minimizes the dipole modes amplitude. The impact of the beam steering in the module on the beam is discussed. A time domain setup is also being presented.
Date: April 10, 2006
Creator: Baboi, N.; Kreps, G.; Schlarb, H.; Wendt, M.; Frisch, J.; McCormick, D. et al.
Object Type: Article
System: The UNT Digital Library
Diffusion through Carbon Nanotube Semipermeable membranes (open access)

Diffusion through Carbon Nanotube Semipermeable membranes

None
Date: February 10, 2006
Creator: Bakajin, O
Object Type: Report
System: The UNT Digital Library
Resistive Wall Wake Effect of a Grooved Vacuum Chamber (open access)

Resistive Wall Wake Effect of a Grooved Vacuum Chamber

We investigate the enhancement of the resistive wall impedance of a round, metallic beam pipe with longitudinal grooves.
Date: February 10, 2006
Creator: Bane, K. L. F. & Stupakov, G.
Object Type: Article
System: The UNT Digital Library
The Role of Demand Response in Default Service Pricing (open access)

The Role of Demand Response in Default Service Pricing

Dynamic retail electricity pricing, especially real-time pricing (RTP), has been widely heralded as a panacea for providing much-needed demand response in electricity markets. However, in designing default service for competitive retail markets, demand response often appears to be an afterthought. But that may be changing as states that initiated customer choice in the past 5-7 years reach an important juncture in retail market design. Most states with retail choice established an initial transitional period, during which utilities were required to offer a default or ''standard offer'' generation service, often at a capped or otherwise administratively-determined rate. Many retail choice states have reached, or are nearing, the end of their transitional period and several states have adopted an RTP-type default service for large commercial and industrial (C&amp;I) customers. Are these initiatives motivated by the desire to induce greater demand response, or is RTP being called upon to serve a different role in competitive markets? Surprisingly, we found that in most cases, the primary reason for adopting RTP as the default service was not to encourage demand response, but rather to advance policy objectives related to the development of competitive retail markets. However, we also find that, if efforts are made in …
Date: March 10, 2006
Creator: Barbose, Galen; Goldman, Chuck & Neenan, Bernie
Object Type: Article
System: The UNT Digital Library
Supporting Photovoltaics in Market-Rate Residential NewConstruction: A Summary of Programmatic Experience to Date and LessonsLearned (open access)

Supporting Photovoltaics in Market-Rate Residential NewConstruction: A Summary of Programmatic Experience to Date and LessonsLearned

As a market segment for solar photovoltaic (PV) adoption, new homes have a number of attractive attributes. Homebuyers can easily roll the cost of the PV system into their tax-deductible home mortgage and, with rebates and other financial incentives, potentially achieve an immediate net-positive cash flow from the investment. New homes are amenable to building-integrated photovoltaics (BIPV), which are less susceptible to aesthetic concerns than traditional, rack-mounted systems. The performance of PV systems can be optimized on new homes by taking roof orientation and shading into account when designing the home. Perhaps most importantly, subdivisions with PV systems installed on a large number of homes offer potential cost savings from volume purchases of modules and inverters and from scale economies in system design and installation. Finally, the ability of builders to install PV as a standard feature on multiple homes in new subdivisions offers an opportunity to circumvent the high transaction costs and information-related market barriers typically confronted when each individual homeowner must make a decision about installing PV. Builders may benefit in several ways from incorporating PV into new homes. Builders may gain greater market differentiation, enhanced media exposure, and less community or political opposition to development projects. Additionally, …
Date: February 10, 2006
Creator: Barbose, Galen; Wiser, Ryan & Bolinger, Mark
Object Type: Report
System: The UNT Digital Library