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CFEST Coupled Flow, Energy & Solute Transport Version CFEST005 Theory Guide

Description: This document presents the mathematical theory implemented in the CFEST (Coupled Flow, Energy, and Solute Transport) simulator. The simulator is a three-dimensional finite element model that can be used for evaluating flow and solute mass transport. Although the theory for thermal transport is presented in this guide, it has not yet been fully implemented in the simulator. The flow module is capable of simulating both confined and unconfined aquifer systems, as well as constant and variable den… more
Date: November 1, 2005
Creator: Freedman, Vicky L.; Chen, Yousu & Gupta, Sumant K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Time-resolved soft-x-ray spectroscopy of a magnetic octupole transition in nickel-like xenon, cesium, and barium ions

Description: A microcalorimeter with event mode capability for time-resolved soft-x-ray spectroscopy, and a high-resolution flat-field EUV spectrometer have been employed at the Livermore EBIT-I electron beam ion trap for observations and wavelength measurements of M1, E2, and M3 decays of long-lived levels in the Ni-like ions Xe{sup 26+}, Cs{sup 27+}, and Ba{sup 28+}. Of particular interest is the lowest excited level, 3d{sup 9}4s {sup 3}D{sub 3}, which can only decay via a magnetic octupole (M3) transitio… more
Date: November 11, 2005
Creator: Trabert, E; Beiersdorfer, P; Brown, G V; Boyce, K; Kelley, R L; Kilbourne, C A et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electron Dynamics of Silicon Surface States: Second-Harmonic HoleBurning on Si(111)7x7

Description: The ultrafast dynamics of electronic excitations of the surface dangling bond states of Si(111) 7 x 7 has been investigated by second harmonic generation as a probe of transient spectral hole burning. Spectral holes induced by a 100 fs pump at {approx_equal} 1.5 eV and their decay are interpreted in terms of electronic dephasing times as short as 15 fs. This fast time scale together with the strong excitation-induced dephasing observed is interpreted in terms of carrier-carrier scattering. In a… more
Date: June 6, 2005
Creator: McGuire, John A.; Raschke, Markus B. & Shen, Yuen-Ron
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Recent Developments in Neutrino Science: A Whole Lot About Almost Nothing

Description: Results from Super-K, SNO, and KamLAND provide strong evidence that neutrinos undergo flavor-changing oscillations and therefore have non-zero mass. The {nu}-disappearance observations by KamLAND, assuming CPT conservation, point to matter enhanced (MSW) oscillations with large mixing angles as the solution to the solar neutrino problem--a result consistent with the MSW parameters recently defined by these experiments. This requires that the observed neutrino flavors (e, {mu}, and tau) are not … more
Date: August 22, 2005
Creator: Norman, E B
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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(Beta)-decay experiments and the unitarity of the CKM matrix

Description: The goal of this project was to perform very precise measurements of super-allowed Fermi {beta} decay in order to investigate a possible non-unitarity in the CKM matrix of the Standard Model of particle physics. Current data from 9 precisely measured {beta} decays indicated that the sum-of-squares of the first row of the CKM matrix differs from 1.0 at the 2.2{sigma} (or 98% confidence) level. If true, it would be the first firm indication of physics beyond the Standard Model--the model that has… more
Date: December 1, 2005
Creator: Garrett, P. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Search for H ---> b anti-b produced in association with W bosons in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: The authors present a search for the standard model Higgs boson decaying into b{bar b} and produced in association with W bosons in p{bar p} collisions at {radical}s = 1.96 TeV. This search uses 320 pb{sup -1} of the dataset accumulated by the upgraded Collider Detector at Fermilab. Events are selected that have a high-transverse momentum electron or muon, missing transverse energy, and two jets, at least one of which is consistent with the hadronization of a b quark. Both the number of events … more
Date: December 1, 2005
Creator: Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, Anthony A.; Akimoto, T.; Albrow, M.G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of the $\tau^- to 3h^- 2h^+ \nu_\tau$ Decay

Description: The branching fraction of the {tau}{sup -} {yields} 3h{sup -} 2h{sup +} {nu}{sub {tau}} decay (h = {pi}, K) is measured with the BABAR detector to be (8.56 {+-} 0.05 {+-} 0.42) x 10{sup -4}, where the first error is statistical and the second systematic. The observed structure of this decay is significantly different from the phase space prediction, with the {rho} resonance playing a strong role. The decay {tau}{sup -} {yields} f{sub 1}(1285){pi}{sup -}{nu}{sub {tau}}, with the f{sub 1}(1285) m… more
Date: May 4, 2005
Creator: Aubert, Bernard; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Consequences of Urban Stability Conditions for Computational Fluid Dynamics Simulations of Urban Dispersion

Description: The validity of omitting stability considerations when simulating transport and dispersion in the urban environment is explored using observations from the Joint URBAN 2003 field experiment and computational fluid dynamics simulations of that experiment. Four releases of sulfur hexafluoride, during two daytime and two nighttime intensive observing periods, are simulated using the building-resolving computational fluid dynamics model, FEM3MP to solve the Reynolds Averaged Navier-Stokes equations… more
Date: November 30, 2005
Creator: Lundquist, J K & Chan, S T
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Revisiting the U-238 thermal capture cross section and gamma-raymission probabilities from Np-239 decay

Description: The precise value of the thermal capture cross section of238U is uncertain, and evaluated cross sections from various sourcesdiffer by more than their assigned uncertainties. A number of theoriginal publications have been reviewed to assess the discrepant data,corrections were made for more recent standard cross sections andotherconstants, and one new measurement was analyzed. Due to the strongcorrelations in activation measurements, the gamma-ray emissionprobabilities from the beta decay of 23… more
Date: March 3, 2005
Creator: Trkov, A.; Molnar, G. L.; Revay, Z. S.; Mughabghab, S. F.; Firestone, R. B.; Pronyaev, V. G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of t anti-t production in tau jets channel at CDFII using neural networks

Description: CDF (Collider Detector at Fermilab) is a particle detector located at Fermi National Laboratories, near Chicago. it allows to study decay products of p{bar p} collisions at center-of-mass energy of 1.96 TeV. During its first period of data taking (RunI), CDF observed for the first time the top quark (1995). The current period of data taking (RunII) is devoted to precise measurements of top properties and to search for new physics. This thesis work is about the top decay channel named {tau} + je… more
Date: December 1, 2005
Creator: Amerio, Silvia
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Reconstructing Past Ocean Salinity ((delta)18Owater)

Description: Temperature and salinity are two of the key properties of ocean water masses. The distribution of these two independent but related characteristics reflects the interplay of incoming solar radiation (insolation) and the uneven distribution of heat loss and gain by the ocean, with that of precipitation, evaporation, and the freezing and melting of ice. Temperature and salinity to a large extent, determine the density of a parcel of water. Small differences in temperature and salinity can increas… more
Date: November 23, 2005
Creator: Guilderson, T. P. & Pak, D. K.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
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Naturalness and Higgs Decays in the MSSM with a Singlet

Description: The simplest extension of the supersymmetric standard model--the addition of one singlet superfield--can have a profound impact on the Higgs and its decays. We perform a general operator analysis of this scenario, focusing on the phenomenologically distinct scenarios that can arise, and not restricting the scope to the narrow framework of the NMSSM. We reexamine decays to four b quarks and four {tau}'s, finding that they are still generally viable, but at the edge of LEP limits. We find a broad… more
Date: November 21, 2005
Creator: Chang, Spencer; Fox, Patrick J. & Weiner, Neal
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simultaneous time and frequency resolved fluorescence microscopy of single molecules.

Description: Single molecule fluorophores were studied for the first time with a new confocal fluorescence microscope that allows the wavelength and emission time to be simultaneously measured with single molecule sensitivity. In this apparatus, the photons collected from the sample are imaged through a dispersive optical system onto a time and position sensitive detector. This detector records the wavelength and emission time of each detected photon relative to an excitation laser pulse. A histogram of man… more
Date: January 1, 2005
Creator: Hayden, Carl C.; Gradinaru, Claudiu C.; Chandler, David W. & Luong, A. Khai
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Di-boson production and SM SUSY Higgs searches at the Tevatron

Description: The discovery of the Higgs boson would be a major success for the Standard Model (SM) and would provide further insights into the electroweak symmetry breaking mechanism. This report contains the latest results from the D0 and CDF Tevatron experiments on searches for the SM Higgs produced from gluon fusion with H {yields} WW, and in association with a W boson. It also includes searches for a supersymmetric Higgs in the b{bar b} and {tau}{sup +}{tau}{sup -} decay channels. The study of di-boson … more
Date: July 1, 2005
Creator: Elvira, V. Daniel
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fitting the luminosity decay in the Tevatron

Description: This paper explores how to fit the decay of the luminosity in the Tevatron. The standard assumptions of a fixed-lifetime exponential decay are only appropriate for very short time intervals. A ''1/time'' functional form fits well, and is supported by analytical derivations. A more complex form, assuming a time-varying lifetime-like term, also produces good results. Changes in the luminosity can be factored into two phenomena: The luminosity burn-off rate, and the burn-off rate from non-luminosi… more
Date: May 1, 2005
Creator: McCrory, E.; Shiltsev, V.; Slaughter, A. J. & Xiao, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of the decay asymmetry parameter and CP violation parameter in the Lambda(c)+ ---> Lambda pi+ decay

Description: Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement of the weak decay-asymmetry parameter a{sub {Lambda}{sub c}} in {Lambda}{sub c}{sup +} {yields} {Lambda}{pi}{sup +} decay. Comparing particle with antiparticle decays, we obtain the first measurement of the CP violation parameter {Alpha} {triple_bond} a{sub {Lambda}{sub c}} + a{sub {ovr {Lambda}{sub c}}}/a{sub {Lambda}{sub c}} - a{sub {ovr {Lambda}{sub c}}}. We obtain a{sub {Lambda}{sub c}} = -0.78 {+-} 0.16 {… more
Date: September 1, 2005
Creator: Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Search for supersymmetric Higgs bosons in the di-tau decay mode in p anti-p collisions at s**(1/2) = 1.8-TeV

Description: A search for direct production of Higgs bosons in the di-tau decay mode is performed with 86.3 {+-} 3.5 pb{sup -1} of data collected with the Collider Detector at Fermilab during the 1994-1995 data taking period of the Tevatron. We search for events where one tau decays to an electron plus neutrinos and the other tau decays hadronically. We perform a counting experiment and set limits on the cross section for supersymmetric Higgs boson production where tan {beta} is large and m{sub A} is small.… more
Date: June 1, 2005
Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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National Renewable Energy Laboratory 2004 Research Review

Description: In-depth articles on several NREL technologies and advances, including: aligning quantum dots and related nanoscience and nanotechnology research; using NREL's Advanced Automotive Manikin (ADAM) to help test and design ancillary automotive systems; and harvesting ocean wind to generate electricity with deep-water wind turbines. Also covered are NREL news, research updates, and awards and honors received by the Laboratory.
Date: March 1, 2005
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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Relationship of Recombination Lifetime and Dark Current In Silicon p-n Junctions

Description: Measurement of recombination and minority-carrier lifetimes has become a central activity in photovoltaic technology. The primary measurement techniques for silicon technologies are based on photoconductive decay (PCD) and microwave reflectance (mPCD). The measurement of the correct recombination lifetime depends on the carriers being confined to a given spatial region of a diagnostic structure. The internal electric fields separate the charges, and the measured value does not represent the rea… more
Date: February 1, 2005
Creator: Ahrenkiel, R. K.; Metzger, W. K.; Page, M.; Reedy, R.; Luther, J. & Dashdorj, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Rare decay K+ ---> pi+ nu anti-nu at the next-to-next-to-leading order in QCD

Description: The authors calculate the complete next-to-next-to-leading order QCD correction of the charm quark contribution to the branching ratio for the rare decay K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} in the standard model. The inclusion of these {Omicron}({alpha}{sub s}) contributions leads to a significant reduction of the theoretical uncertainty from {+-} 10.1% down to {+-} 2.4% in the relevant parameter P{sub c}, implying the left over scale uncertainties in {Beta}(K{sup +} {yields} {pi}{sup +… more
Date: August 1, 2005
Creator: Buras, A. J.; Gorbahn, M.; Haisch, U. & Nierste, U.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Top physics results from CDF

Description: The top quark is by far the most massive fundamental particle observed so far, and the study of its properties is interesting for several reasons ranging from its possible special role in electroweak symmetry breaking to its sensitivity to physics beyond the Standard Model. They present recent top physics results from CDF based on 160-320 pb{sup -1} of p{bar p} collision data at {radical}s = 1.96 TeV. The t{bar t} cross section and the top mass have been measured in different decay channels and… more
Date: May 1, 2005
Creator: Gomez, Gervasio
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Measurement of the K0 charge radius and a CP violating asymmetry together with a search for CP violating e1 direct photon emission in the rare decay K(L) ---> pi+ pi- e+ e-

Description: Using the complete KTeV data set of 5241 candidate K{sub L} {yields} {pi}{sup +}{pi}{sup -}e{sup +}e{sup -} decays (including an estimated background of 204 {+-} 14 events), we have measured the coupling g{sub CR} = 0.163 {+-} 0.014 (stat) {+-} 0.023 (syst) of the CP conserving charge radius process and from it determined a K{sup 0} charge radius of <r{sub K{sup 0}}{sup 2}> = (-0.077 {+-} 0.007(stat) {+-} 0.011(syst))fm{sup 2}. We have also determined a first experimental upper limit of 0… more
Date: August 1, 2005
Creator: Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Bellavance, A.; Blucher, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Search for a strongly decaying neutral charmed pentaquark

Description: We present a search for a charmed pentaquark decaying strongly to D{sup (*)}-p. Finding no evidence for such a state, we set limits on the cross section times branching ratio relative to D*{sup -} and D{sup -} under particular assumptions about the production mechanism.
Date: June 1, 2005
Creator: Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of field decay and snapback effect on Tevatron dipole and quadrupole magnets

Description: Since the beginning of 2002 an intensive measurement program has been performed at the Fermilab Magnet Test Facility (MTF) to understand dynamic effects in Tevatron magnets. Based on the results of this program a new correction algorithm was proposed to compensate for the decay of the sextupole field during the dwell at injection and for the subsequent field ''snapback'' during the first few seconds of the energy ramp. Beam studies showed that the new correction algorithm works better than the … more
Date: May 1, 2005
Creator: Velev, G. V.; Ambrosio, G.; Annala, G.; Bauer, P.; Carcagno, R.; DiMarco, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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