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Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling - Is Single Pass Cooling Possible? (open access)

Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling - Is Single Pass Cooling Possible?

N/A
Date: April 1, 2008
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Search for Heavy, Long-Lived Neutralinos that Decay to Photons at CDF II Using Photon Timing (open access)

Search for Heavy, Long-Lived Neutralinos that Decay to Photons at CDF II Using Photon Timing

The authors present the results of the first hadron collider search for heavy, long-lived neutralinos that decay via {tilde {chi}}{sub 1}{sup 0} {yields} {gamma}{tilde G} in gauge-mediated supersymmetry breaking models. Using an integrated luminosity of 570 {+-} 34 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, they select {gamma}+jet+missing transverse energy candidate events based on the arrival time of a high-energy photon at the electromagnetic calorimeter as measured with a timing system that was recently installed on the CDF II detector. They find 2 events, consistent with the background estimate of 1.3 {+-} 0.7 events. While the search strategy does not rely on model-specific dynamics, they set cross section limits and place the world-best 95% C.L. lower limit on the {tilde {chi}}{sub 1}{sup 0} mass of 101 GeV/c{sup 2} at {tau}{sub {tilde {chi}}{sub 1}{sup 0}} = 5 ns.
Date: April 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Search for the Rare Decays B^+ -> mu^+ mu^- K^+, B^0 -> mu^+ mu^- K^*0(892), and B^0_s -> mu^+ mu^- phi at CDF (open access)

Search for the Rare Decays B^+ -> mu^+ mu^- K^+, B^0 -> mu^+ mu^- K^*0(892), and B^0_s -> mu^+ mu^- phi at CDF

The authors search for b {yields} s{mu}{sup +}{mu}{sup -} transitions in B meson (B{sup +}, B{sup 0}, or B{sub s}{sup 0}) decays with 924 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. They find excesses with significances of 4.5, 2.9, and 2.4 standard deviations in the B{sup +} {yields} {mu}{sup +}{mu}{sup -}K{sup +}, B{sup 0} {yields} {mu}{sup +}{mu}{sup -}K*(892){sup 0}, and B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}{phi} decay modes, respectively. Using B {yields} J/{psi}h (h - K{sup +}, K*(892){sup 0}, {phi}) decays as normalization channels, they report branching fractions for the previously observed B{sup +} and B{sup 0} decays as normalization channels, they report branching fractions for the previously observed B{sup +} and B{sup 0} decays, {Beta}(B{sup +} {yields} {mu}{sup +}{mu}{sup -}K{sup +}) = (0.59 {+-} 0.15 {+-} 0.04) x 10{sup -6}, and {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}K*(892){sup 0}) = (0.81 {+-} 0.30 {+-} 0.10) x 10{sup -6}, where the first uncertainty is statistical, and the second is systematic. These measurements are consistent with the world average results, and are competitive with the best available measurements. They set an upper limit on the relative branching …
Date: April 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the forward-backward charge asymmetry and extraction of $sin^2Theta^{eff}_W$ in $p\bar{p} \to Z/\gamma^{*}+X \to e^+e^-+X$ events produced at $\sqrt{s}=1.96$ TeV (open access)

Measurement of the forward-backward charge asymmetry and extraction of $sin^2Theta^{eff}_W$ in $p\bar{p} \to Z/\gamma^{*}+X \to e^+e^-+X$ events produced at $\sqrt{s}=1.96$ TeV

We present a measurement of the forward-backward charge asymmetry (A{sub FB}) in p{bar p} {yields} Z/{gamma}* + X {yields} e{sup +}e{sup -} + X events at a center-of-mass energy of 1.96 TeV using 1.1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider. A{sub FB} is measured as a function of the invariant mass of the electron-positron pair, and found to be consistent with the standard model prediction. We use the A{sub FB} measurement to extract the effective weak mixing angle sin{sup 2} {theta}{sub W}{sup eff} = 0.2327 {+-} 0.0018 (stat.) {+-} 0.0006 (syst.).
Date: April 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the polarization of the $\Upsilon(1S)$ and $\Upsilon(2S)$ states in $p\bar{p}$ collisions at $\sqrt{s}=$1.96 TeV (open access)

Measurement of the polarization of the $\Upsilon(1S)$ and $\Upsilon(2S)$ states in $p\bar{p}$ collisions at $\sqrt{s}=$1.96 TeV

We present a study of the polarization of the {Upsilon}(1S) and {Upsilon}(2S) states using a 1.3 fb{sup -1} data sample collected by the D0 experiment in 2002-2006 during Run II of the Fermilab Tevatron Collider. We measure the polarization parameter {alpha} = ({sigma}{sub T} - 2{sigma}{sub L})/({sigma}{sub T} + 2{sigma}{sub L}), where {sigma}{sub T} and {sigma}{sub L} are the transversely and longitudinally polarized components of the production cross section, as a function of the transverse momentum (p{sub T}{sup {Upsilon}}) for the {Upsilon}(1S) and {Upsilon}(2S). Significant p{sub T}{sup {Upsilon}}-dependent longitudinal polarization is observed for the {Upsilon}(1S). A comparison with theoretical models is presented.
Date: April 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Anode Sheath Switching in a Carbon Nanotube Arc Plasma (open access)

Anode Sheath Switching in a Carbon Nanotube Arc Plasma

The anode ablation rate is investigated as a function of anode diameter for a carbon nanotube arc plasma. It is found that anomalously high ablation occurs for small anode diameters. This result is explained by the formation of a positive anode sheath. The increased ablation rate due to this positive anode sheath could imply greater production rate for carbon nanotubes.
Date: April 8, 2008
Creator: Abe Fetterman, Yevgeny Raitses, and Michael Keidar
Object Type: Report
System: The UNT Digital Library
Correlation and Prediction of Partition Coefficients from the Gas Phase and from Water to Alkan-1-ols (open access)

Correlation and Prediction of Partition Coefficients from the Gas Phase and from Water to Alkan-1-ols

Article discussing correlation and prediction of partition coefficients from the gas phase and from water to alkan-1-ols.
Date: April 22, 2008
Creator: Abraham, M. H. (Michael H.); Nasezadeh, Asadollah & Acree, William E. (William Eugene)
Object Type: Article
System: The UNT Digital Library

Ensemble: 2008-04-05 – African Cultural Festival

Access: Use of this item is restricted to the UNT Community
Concert presented at the UNT College of Music Concert Hall.
Date: April 5, 2008
Creator: Afrikania Cultural Troupe of Ghana, West Africa
Object Type: Sound
System: The UNT Digital Library
European Union–U.S. Trade and Investment Relations: Key Issues (open access)

European Union–U.S. Trade and Investment Relations: Key Issues

None
Date: April 8, 2008
Creator: Aheam, Raymond J.; Fischer, John W.; Goldfarb, Charles B.; Hanrahan, Charles E.; Eubanks, Walter W. & Rubin, Janice E.
Object Type: Report
System: The UNT Digital Library
Ultrabright Laser-based MeV-class Light Source (open access)

Ultrabright Laser-based MeV-class Light Source

We report first light from a novel, new source of 10-ps 0.776-MeV gamma-ray pulses known as T-REX (Thomson-Radiated Extreme X-rays). The MeV-class radiation produced by TREX is unique in the world with respect to its brightness, spectral purity, tunability, pulse duration and laser-like beam character. With T-REX, one can use photons to efficiently probe and excite the isotope-dependent resonant structure of atomic nucleus. This ability will be enabling to an entirely new class of isotope-specific, high resolution imaging and detection capabilities.
Date: April 2, 2008
Creator: Albert, F.; Anderson, G.; Anderson, S.; Bayramian, A.; Berry, B.; Betts, S. et al.
Object Type: Article
System: The UNT Digital Library
Model-Independent Analysis of Tri-bimaximal Mixing: A Softly-Broken Hidden or an Accidental Symmetry? (open access)

Model-Independent Analysis of Tri-bimaximal Mixing: A Softly-Broken Hidden or an Accidental Symmetry?

To address the issue of whether tri-bimaximal mixing (TBM) is a softly-broken hidden or an accidental symmetry, we adopt a model-independent analysis in which we perturb a neutrino mass matrix leading to TBM in the most general way but leave the three texture zeros of the diagonal charged lepton mass matrix unperturbed. We compare predictions for the perturbed neutrino TBM parameters with those obtained from typical SO(10) grand unified theories with a variety of flavor symmetries. Whereas SO(10) GUTs almost always predict a normal mass hierarchy for the light neutrinos, TBM has a priori no preference for neutrino masses. We find, in particular for the latter, that the value of |U{sub e3}| is very sensitive to the neutrino mass scale and ordering. Observation of |U{sub e3}|{sup 2} > 0.001 to 0.01 within the next few years would be incompatible with softly-broken TBM and a normal mass hierarchy and would suggest that the apparent TBM symmetry is an accidental symmetry instead. No such conclusions can be drawn for the inverted and quasi-degenerate hierarchy spectra.
Date: April 1, 2008
Creator: Albright, Carl H. & Rodejohann, Werner
Object Type: Article
System: The UNT Digital Library
Environmental Exemptions for the Navy's Mid-Frequency Active Sonar Training Program (open access)

Environmental Exemptions for the Navy's Mid-Frequency Active Sonar Training Program

This report discusses laws related to the protection of marine mammals when using mid-frequency active sonar including the Marine Mammal Protection Act (MMPA), the Endangered Species Act (ESA), the National Environmental Policy Act (NEPA), and the Coastal Zone Management Act (CZMA). The report discusses each of the laws generally, and then reviews the litigation surrounding the Navy's compliance with these laws in the context of using the sonar for training purposes off California's coast.
Date: April 15, 2008
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 14, Ed. 1 Thursday, April 3, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 14, Ed. 1 Thursday, April 3, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: April 3, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 15, Ed. 1 Thursday, April 10, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 15, Ed. 1 Thursday, April 10, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: April 10, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 16, Ed. 1 Thursday, April 17, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 16, Ed. 1 Thursday, April 17, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: April 17, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 17, Ed. 1 Thursday, April 24, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 17, Ed. 1 Thursday, April 24, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: April 24, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Isolation of Discrete Nanoparticle-DNA Conjugates for Plasmonic Applications (open access)

Isolation of Discrete Nanoparticle-DNA Conjugates for Plasmonic Applications

Discrete DNA-gold nanoparticle conjugates with DNA lengths as short as 15 bases for both 5 nm and 20 nm gold particles have been purified by anion-exchange HPLC. Conjugates comprising short DNA (<40 bases) and large gold particles (>_ 20 nm) are difficult to purify by other means, and are potential substrates for plasmon coupling experiments. Conjugate purity is demonstrated by hybridizing complementary conjugates to form discrete structures, which are visualized by TEM.
Date: April 11, 2008
Creator: Alivisatos, Paul; Claridge, Shelley A.; Liang, Huiyang W.; Basu, Sourav Roger; Frechet, Jean M.J. & Alivisatos, A. Paul
Object Type: Article
System: The UNT Digital Library
An interaction-based access control model (IBAC) for collaborative services (open access)

An interaction-based access control model (IBAC) for collaborative services

A collaboration is a collection of services that work together to achieve a common goal. Although collaborations help when tackling difficult problems, they lead to security issues. First, a collaboration is often performed by services that are drawn from different security domains. Second, a service interacts with multiple peer services during the collaboration. These interactions are not isolated from one another--e.g., data may flow through a sequence of different services. As a result, a service is exposed to multiple peer services in varying degrees, leading to different security threats. We identify the types of interactions that can be present in collaborations, and discuss the security threats due to each type. We propose a model for representing the collaboration context so that a service can be made aware of the existing interactions. We provide an access control model for a service participating in a collaboration. We couple our access control model with a policy model, so that the access requirements from collaborations can be expressed and evaluated.
Date: April 1, 2008
Creator: Altunay, Mine; Byrd, Gregory T.; Brown, Doug E. & Dean, Ralph A.
Object Type: Article
System: The UNT Digital Library
Time-periodic solutions of the Benjamin-Ono equation (open access)

Time-periodic solutions of the Benjamin-Ono equation

We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump …
Date: April 1, 2008
Creator: Ambrose , D.M. & Wilkening, Jon
Object Type: Article
System: The UNT Digital Library
Guide to Individuals Seated on the House Dais (open access)

Guide to Individuals Seated on the House Dais

This report provides information about the Guide to Individuals Seated on the House Dais. The house of representatives meets in the capitol in the house chamber.
Date: April 24, 2008
Creator: Amer, Mildred
Object Type: Report
System: The UNT Digital Library
House and Senate Chaplains (open access)

House and Senate Chaplains

None
Date: April 25, 2008
Creator: Amer, Mildred
Object Type: Report
System: The UNT Digital Library
The Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11 (open access)

The Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11

this report provides information about the Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11.
Date: April 11, 2008
Creator: Amy, Belsaco
Object Type: Report
System: The UNT Digital Library
Health Physics Enrollments and Degrees Survey, 2007 Data (open access)

Health Physics Enrollments and Degrees Survey, 2007 Data

The survey includes degrees granted between September 1, 2006 and August 31, 2007. Enrollment information refers to the fall term 2007. Twenty-nine academic programs were included in the survey universe, and 28 of the 29 responded. The report includes data by degree level including citizenship, gender, and race/ethnicity plus enrollments of junior and senior undergraduate students and graduate students.
Date: April 1, 2008
Creator: Analysis and Evaluation, Science Education Programs
Object Type: Report
System: The UNT Digital Library
Fluorine for Hydrogen Exchange in the Hydrofluorobenzene Derivatives C6HxF(6-x), where x = 2, 3, 4 and 5 by Monomeric [1,2,4-(Me3C)3C5H2]2CeH; The Solid State Isomerization of [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,5-C6HF4) to [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,6-C6HF4) (open access)

Fluorine for Hydrogen Exchange in the Hydrofluorobenzene Derivatives C6HxF(6-x), where x = 2, 3, 4 and 5 by Monomeric [1,2,4-(Me3C)3C5H2]2CeH; The Solid State Isomerization of [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,5-C6HF4) to [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,6-C6HF4)

The reaction between monomeric bis(1,2,4-tri-t-butylcyclopentadienyl)cerium hydride, Cp&#39;2CeH, and several hydrofluorobenzene derivatives is described. The aryl derivatives that are the primary products, Cp&#39;2Ce(C6H5-xFx) where x = 1,2,3,4, are thermally stable enough to be isolated in only two cases, since all of them decompose at different rates to Cp&#39;2CeF and a fluorobenzyne; the latter is trapped by either solvent when C6D6 is used or by a Cp&#39;H ring when C6D12 is the solvent. The trapped products are identified by GCMS analysis after hydrolysis. The aryl derivatives are generated cleanly by reaction of the metallacycle, Cp&#39;((Me3C)2C5H2C(Me2)CH2)Ce, with a hydrofluorobenzene and the resulting arylcerium products, in each case, are identified by their 1H and 19F NMR spectra at 20oC. The stereochemical principle that evolves from these studies is that the thermodynamic isomer is the one in which the CeC bond is flanked by two ortho-CF bonds. This orientation is suggested to arise from the negative charge that is localized on the ipso-carbon atom due to Co(delta+)-Fo(delta-) polarization. The preferred regioisomer is determined by thermodynamic rather than kinetic effects; this is illustrated by the quantitative, irreversible solid-state conversion at 25oC over two months of Cp&#39;2Ce(2,3,4,5-C6HF4) to Cp&#39;2Ce(2,3,4,6-C6HF4), an isomerization that involves a CeC(ipso) for C(ortho)F …
Date: April 21, 2008
Creator: Andersen, Richard; Werkema, Evan L. & Andersen, Richard A.
Object Type: Article
System: The UNT Digital Library