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SIAM Workshop on Combinatorial Scientific Computing February 27-28, 2004 San Francisco, CA (open access)

SIAM Workshop on Combinatorial Scientific Computing February 27-28, 2004 San Francisco, CA

None
Date: October 4, 2004
Creator: /a, n
Object Type: Report
System: The UNT Digital Library
Greenidge Multi-Pollutant Control Project (Part 2) (open access)

Greenidge Multi-Pollutant Control Project (Part 2)

The digital full text of this report is divided into two parts. This part of the report contains five and a half of the twelve appendices of the report.
Date: October 18, 2008
Creator: 960446, See OSTI ID
Object Type: Report
System: The UNT Digital Library
Greenidge Multi-Pollutant Control Project (Part 3) (open access)

Greenidge Multi-Pollutant Control Project (Part 3)

None
Date: October 18, 2008
Creator: 960446, See OSTI ID Number
Object Type: Report
System: The UNT Digital Library
FFAG Accelerator Proton Driver for Neutrino Factory (open access)

FFAG Accelerator Proton Driver for Neutrino Factory

N/A
Date: October 1, 2005
Creator: A., Ruggiero
Object Type: Report
System: The UNT Digital Library
CRYSTALLIZATION IN MULTICOMPONENT GLASSES (open access)

CRYSTALLIZATION IN MULTICOMPONENT GLASSES

In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.
Date: October 8, 2009
Creator: AA, KRUGER & PR, HRMA
Object Type: Article
System: The UNT Digital Library
PROPOSAL FOR A SILICON VERTEX TRACKER (VTX) FOR THE PHENIX EXPERIMENT (open access)

PROPOSAL FOR A SILICON VERTEX TRACKER (VTX) FOR THE PHENIX EXPERIMENT

We propose the construction of a Silicon Vertex Tracker (VTX) for the PHENIX experiment at RHIC. The VTX will substantially enhance the physics capabilities of the PHENIX central arm spectrometers. Our prime motivation is to provide precision measurements of heavy-quark production (charm and beauty) in A+A, p(d)+A, and polarized p+p collisions. These are key measurements for the future RHIC program, both for the heavy ion program as it moves from the discovery phase towards detailed investigation of the properties of the dense nuclear medium created in heavy ion collisions, and for the exploration of the nucleon spin-structure functions. In addition, the VTX will also considerably improve other measurements with PHENIX. The main physics topics addressed by the VTX are: (1) Hot and dense strongly interacting matter--(a) Potential enhancement of charm production, (b) Open beauty production, (c) Flavor dependence of jet quenching and QCD energy loss, (d) Accurate charm reference for quarkonium, (e) Thermal dilepton radiation, (f) High p{sub T} phenomena with light flavors above 10-15 GeV/c in p{sub T}, and (g) Upsilon spectroscopy in the e{sup +}e{sup -} decay channel. (2) Gluon spin structure of the nucleon--(a) {Delta}G/G with charm, (b) {Delta}G/G with beauty, and (c) x dependence of {Delta}G/G …
Date: October 1, 2004
Creator: AKIBA,Y.
Object Type: Report
System: The UNT Digital Library
HYBRIDIZATION AND PRESSURE EFFECTS IN UTX COMPOUNDS (open access)

HYBRIDIZATION AND PRESSURE EFFECTS IN UTX COMPOUNDS

None
Date: October 1, 2001
Creator: ALSAMDI, A.; SECHOVSKY, V. & AL, ET
Object Type: Article
System: The UNT Digital Library
Development of An On-Line, Core Power Distribution Monitoring System (open access)

Development of An On-Line, Core Power Distribution Monitoring System

The objective of the proposed work was to develop a software package that can construct in three-dimensional core power distributions using the signals from constant temperature power sensors distributed in the reactor core. The software developed uses a mode-based state/parameter estmation technique that is particularly attractive when there are model uncertainties and/or large signal noise. The software yields the expected value of local power at the detector locations and points in between, as well as the probability distribution of the local power density
Date: October 2, 2007
Creator: ALdemir, Tunc; Miller, Don & Wang, Peng
Object Type: Report
System: The UNT Digital Library
SATURATED ZONE FLOW AND TRANSPORT MODEL ABSTRACTION (open access)

SATURATED ZONE FLOW AND TRANSPORT MODEL ABSTRACTION

The purpose of the saturated zone (SZ) flow and transport model abstraction task is to provide radionuclide-transport simulation results for use in the total system performance assessment (TSPA) for license application (LA) calculations. This task includes assessment of uncertainty in parameters that pertain to both groundwater flow and radionuclide transport in the models used for this purpose. This model report documents the following: (1) The SZ transport abstraction model, which consists of a set of radionuclide breakthrough curves at the accessible environment for use in the TSPA-LA simulations of radionuclide releases into the biosphere. These radionuclide breakthrough curves contain information on radionuclide-transport times through the SZ. (2) The SZ one-dimensional (I-D) transport model, which is incorporated in the TSPA-LA model to simulate the transport, decay, and ingrowth of radionuclide decay chains in the SZ. (3) The analysis of uncertainty in groundwater-flow and radionuclide-transport input parameters for the SZ transport abstraction model and the SZ 1-D transport model. (4) The analysis of the background concentration of alpha-emitting species in the groundwater of the SZ.
Date: October 27, 2004
Creator: ARNOLD, B.W.
Object Type: Report
System: The UNT Digital Library
THE FUTURE OF SPIN PHYSICS AT BNL. (open access)

THE FUTURE OF SPIN PHYSICS AT BNL.

The Relativistic Heavy Ion Collider (RHIC) at BNL is the world's only polarized proton-proton collider. Collisions at center-of-mass energies up to 500 GeV and beam polarizations approaching 70% (longitudinal or transverse) are provided to two experiments, STAR and PHENIX, at luminosities {ge} 10{sup 32}/cm{sup 2}/sec. Transverse polarized beam has also been provided to the BRAHMS experiment. Measurements that bear on the important question of the spin content of the nucleon are beginning to appear. Over the next 10 years, as the performance of polarized proton running at RHIC is further developed, the Spin Physics program at RHIC will provide definitive measurements of the contributions to the proton's spin of the gluon, the sea quarks and the orbital motion of the partons in the proton's wave function. We plan to extend the reach of our study of the role of spin in QCD with the development of ''eRHIC'', which will provide polarized e-p collisions to a new detector.
Date: October 2, 2006
Creator: ARONSON, S. & DESHPANDE, A.
Object Type: Article
System: The UNT Digital Library
Construction and Testing of a Low-power Cryostat for MARS (open access)

Construction and Testing of a Low-power Cryostat for MARS

A low-power cryostat was designed and built for the Multi-sensor Airborne Radiation Survey (MARS) project for the purpose of housing a close-packed high-purity germanium (HPGe) detector array of 14 HPGe detectors. The power consumption of the cold mass in the cryostat was measured to be 4.07(11) watts, sufficient for 5.5 days of continuous operation using only 8 liters of liquid nitrogen. Temperatures throughout the cryostat were measured by platinum resistance temperature detectors. These measurements were used to determine the emissivity of the copper used in the floating radiation shield and outer cryostat wall, which was constructed using chemically cleaned and passivated copper metal. Using a PNNL-developed passivation process, an emissivity of 2.5(3)% was achieved for copper.
Date: October 1, 2007
Creator: Aalseth, Craig E.; Caggiano, Joseph A.; Day, Anthony R.; Fast, James E. & Fuller, Erin S.
Object Type: Report
System: The UNT Digital Library
Search for Standard Model Higgs Bosons Produced in Association with W Bosons (open access)

Search for Standard Model Higgs Bosons Produced in Association with W Bosons

The authors report on the results of a search for standard model Higgs bosons produced in association with W bosons from p{bar p} collisions at {radical}s = 1.96 TeV. The search uses a data sample corresponding to approximately 1 fb{sup -1} of integrated luminosity. Events consistent with the W {yields} {ell}{nu} and H {yields} b{bar b} signature are selected by triggering on a high-p{sub T} electron or muon candidate and tagging one or two of the jet candidates as having originated from b quarks. A neural network filter rejects a fraction of tagged charm and light flavor jets, increasing the b-jet purity in the sample and thereby reducing the background to Higgs boson production. They observe no excess {ell}{nu}b{bar b} production beyond the background expectation, and they set 95% confidence level upper limits on the production cross section times branching fraction {sigma}(p{bar p} {yields} WH) {center_dot} Br(H {yields} b{bar b}) ranging from 3.9 to 1.3 pb, for specific Higgs boson mass hypotheses in the range 110 to 150 GeV/c{sup 2}, respectively.
Date: October 1, 2007
Creator: Aaltonen, T.
Object Type: Article
System: The UNT Digital Library
Measurements of the top-quark mass using charged particle tracking (open access)

Measurements of the top-quark mass using charged particle tracking

We present three measurements of the top-quark mass in the lepton plus jets channel with approximately 1.9 fb{sup -1} of integrated luminosity collected with the CDF II detector using quantities with minimal dependence on the jet energy scale. One measurement exploits the transverse decay length of b-tagged jets to determine a top-quark mass of 166.9{sub -8.5}{sup +9.5} (stat) {+-} 2.9 (syst) GeV/c{sup 2}, and another the transverse momentum of electrons and muons from W-boson decays to determine a top-quark mass of 173.5{sub -8.9}{sup +8.8} (stat) {+-} 3.8 (syst) GeV/c{sup 2}. These quantities are combined in a third, simultaneous mass measurement to determine a top-quark mass of 170.7 {+-} 6.3 (stat) {+-} 2.6 (syst) GeV/c{sup 2}.
Date: October 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Inclusive Isolated Prompt Photon Cross Section in ppbar Collisions at sqrt{s} = 1.96 TeV using the CDF Detector (open access)

Measurement of the Inclusive Isolated Prompt Photon Cross Section in ppbar Collisions at sqrt{s} = 1.96 TeV using the CDF Detector

A measurement of the cross section for the inclusive production of isolated photons by the CDF experiment at the Fermilab Tevatron collider is presented. The measurement covers the pseudorapidity region |{eta}{sup {gamma}}| < 1.0 and the transverse energy range E{sub T}{sup {gamma}} > 30 GeV and is based on 2.5 fb{sup -1} of integrated luminosity. The sample is almost a factor of seven larger than those used for recent published results and extends the E{sub T}{sup {gamma}} coverage by 100 GeV. The result agrees with next-to-leading order perturbative QCD calculations within uncertainties over the range 50 < E{sub T}{sup {gamma}} < 400 GeV, though the energy spectrum in the data shows a steeper slope at lower E{sub T}{sup {gamma}}.
Date: October 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Object Type: Article
System: The UNT Digital Library
Search for Anomalous Production of Events with Two Photons and Additional Energetic Objects at CDF (open access)

Search for Anomalous Production of Events with Two Photons and Additional Energetic Objects at CDF

The authors present results of a search for anomalous production of two photons together with an electron, muon, {tau} lepton, missing transverse energy, or jets using p{bar p} collision data from 1.1-2.0 fb{sup -1} of integrated luminosity collected by the Collider Detector at Fermilab (CDF). The event yields and kinematic distributions are examined for signs for new physics without favoring a specific model of new physics. The results are consistent with the standard model expectations. The search employs several new analysis techniques that significantly reduce instrumental backgrounds in channels with an electron and missing transverse energy.
Date: October 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Object Type: Article
System: The UNT Digital Library
Search for Supersymmetry with Gauge-Mediated Breaking in Diphoton Events with Missing Transverse Energy at CDF II (open access)

Search for Supersymmetry with Gauge-Mediated Breaking in Diphoton Events with Missing Transverse Energy at CDF II

The authors present the results of a search for supersymmetry with gauge-mediated breaking and {tilde {chi}}{sub 1}{sup 0} {yields} {gamma}{tilde G} in the {gamma}{gamma} + missing transverse energy final state. In 2.6 {+-} 0.2 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV recorded by the CDF II detector they observe no candidate events, consistent with a standard model background expectation of 1.4 {+-} 0.4 events. They set limits on the cross section at the 95% C.L. and place the world's best limit of 149 GeV/c{sup 2} on the {tilde {chi}}{sub 1}{sup 0} mass at {tau}{sub {tilde {chi}}{sub 1}{sup 0}} << 1 ns. They also exclude regions in the {tilde {chi}}{sub 1}{sup 0} mass-lifetime plane of {tau}{sub {tilde {chi}}{sub 1}{sup 0}} {approx}< 2 ns.
Date: October 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Object Type: Article
System: The UNT Digital Library
Search for High-Mass \boldmath$e^+e^-$ Resonances in \boldmath$p\bar{p}$ Collisions at \boldmath$\sqrt{s}=$1.96 TeV (open access)

Search for High-Mass \boldmath$e^+e^-$ Resonances in \boldmath$p\bar{p}$ Collisions at \boldmath$\sqrt{s}=$1.96 TeV

A search for high-mass resonances in the e{sup +}e{sup -} final state is presented based on {radical}s =1.96 TeV p{bar p} collision data from the CDF II detector at the Fermilab Tevatron from an integrated luminosity of 2.5 fb{sup -1}. The largest excess over the standard model prediction is at an e{sup +}e{sup -} invariant mass of 240 GeV/c{sup 2}. The probability of observing such an excess arising from fluctuations in the standard model anywhere in the mass range of 150-1,000 GeV/c{sup 2} is 0.6% (equivalent to 2.5 {sigma}). We set Bayesian upper limits on {sigma}(p{bar p} {yields} X) {center_dot} {Beta}(X {yields} e{sup +}e{sup -}) at the 95% credibility level, where X is a spin 1 or spin 2 particle, and we exclude the standard model coupling Z{prime} and the Randall-Sundrum graviton for {kappa}/{bar M}{sub Pl} = 0.1 with masses below 963 and 848 GeV/c{sup 2}, respectively.
Date: October 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
Evidence of WW+WZ production with lepton + jets final states in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Evidence of WW+WZ production with lepton + jets final states in p anti-p collisions at s**(1/2) = 1.96-TeV

We present the first evidence of WW+WZ production with lepton+jets final states at a hadron collider. The data correspond to 1.07 inverse femtobarns of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider in proton-antiproton collisions at sqrt(s)=1.96 TeV. The observed cross section for WW+WZ production is 20.2 +/- 4.5 pb, consistent with the SM prediction of 16.1 +/- 0.9 pb. The probability for background fluctuations to produce an excess equal to or larger than that observed is estimated to be 5.4e-6, corresponding to a significance of 4.4 standard deviations.
Date: October 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
Atmospheric Mercury Concentrations Near Salmon Falls Creek Reservoir - Phase 1 (open access)

Atmospheric Mercury Concentrations Near Salmon Falls Creek Reservoir - Phase 1

Elemental and reactive gaseous mercury (EGM/RGM) were measured in ambient air concentrations over a two-week period in July/August 2005 near Salmon Falls Creek Reservoir, a popular fishery located 50 km southwest of Twin Falls, Idaho. A fish consumption advisory for mercury was posted at the reservoir in 2002 by the Idaho Department of Health and Welfare. The air measurements were part of a multi-media (water, sediment, precipitation, air) study initiated by the Idaho Department of Environmental Quality and the U.S. Environmental Protection Agency (EPA) Region 10 to identify potential sources of mercury contamination to the reservoir. The sampling site is located about 150 km northeast of large gold mining operations in Nevada, which are known to emit large amounts of mercury to the atmosphere (est. 2,200 kg/y from EPA 2003 Toxic Release Inventory). The work was co-funded by the Idaho National Laboratory’s Community Assistance Program and has a secondary objective to better understand mercury inputs to the environment near the INL, which lies approximately 230 km to the northeast. Sampling results showed that both EGM and RGM concentrations were significantly elevated (~ 30 – 70%, P<0.05) compared to known regional background concentrations. Elevated short-term RGM concentrations (the primary form that …
Date: October 1, 2005
Creator: Abbott, M. L.
Object Type: Report
System: The UNT Digital Library
Environmental Sampling FY03 Annual Report - Understanding the Movement of Mercury on the INEEL (open access)

Environmental Sampling FY03 Annual Report - Understanding the Movement of Mercury on the INEEL

Environmental mercury measurements were started in Fy-01 at the Idaho National Engineering Laboratory (INEEL) to monitor downwind impacts from on-going waste treatment operations at the Idaho Nuclear Technology and Engineering Center (INTEC) and to improve our scientific understanding of mercury fate and transport in this region. This document provides a summary of the sampling done in FY04. Continuous total gaseous mercury (TGM) measurements were made using a Tekran Model 2537A mercury vapor analyzer during October 2002 and from February through July 2003. The equipment was deployed in a self-contained field trailer at the Experimental Field Station (EFS) four kilometers downwind (northeast) of INTEC. Mercury surface-to-air flux measurements were made in October 2002 and from February through May 2003 to better understand the fate of the estimated 1500 kg of mercury emitted from 36 years of calciner operations at INTEC and to improve our scientific understanding of mercury environmental cycling in this region. Flux was measured using an INEEL-designed dynamic flux chamber system with a Tekran automated dual sampling (TADS) unit. Diel flux was positively correlated with solar radiation (r = 0.65), air temperature (r = 0.64), and wind speed (r = 0.38), and a general linear model for flux prediction …
Date: October 1, 2003
Creator: Abbott, Michael L.
Object Type: Report
System: The UNT Digital Library
The Dynamic Response of Thick-Liquid Shielding in Z-IFE Reactors (open access)

The Dynamic Response of Thick-Liquid Shielding in Z-IFE Reactors

A major concern in the design of thick-liquid protected inertial fusion reactors of all types is the dynamic response of the shielding liquid to the pulsed explosions. Induced liquid motion can stress and damage solid chamber structures such as the firstwall. In a z-pinch based inertial fusion (Z-IFE) reactor this issue becomes particularly critical due to the relatively large proposed target yields of several GJ. In this paper we summarize an analysis of the liquid response taking into account ablation of target facing surfaces, pocket venting, and neutron isochoric heating. The impact of varying several reactor parameters is also discussed.
Date: October 5, 2005
Creator: Abbott, R P
Object Type: Article
System: The UNT Digital Library
A Fusion Chamber for the 2002 Robust Point Design (open access)

A Fusion Chamber for the 2002 Robust Point Design

A top-level overview of the mechanical design for the 2002 Robust Point Design (RPD-2002) fusion chamber is introduced. It is based on the HYLIFE-II design and includes modifications to the liquid pocket configuration and first structural wall (FSW), facilitates periodic maintenance or replacement of internal components, and is compliant with all other RPD-2002 parameters. This work has been carried out by constructing a parametric computer model capable of being updated as future changes become necessary.
Date: October 1, 2003
Creator: Abbott, R P
Object Type: Article
System: The UNT Digital Library
Effects of Light Scalar Mesons in eta -&gt; 3pi decay (open access)

Effects of Light Scalar Mesons in eta -&gt; 3pi decay

We study the role of a possible nonet of light scalar mesons in the still interesting [eta] -&gt; 3[p]i decay process, with the primary motivation of learning more about the scalars themselves. The framework is a conventional non-linear chiral Lagrangian of pseudoscalars and vectors extended to include the scalars. The parameters involving the scalars were previously obtained to fit the s-wave [pi][pi] and [pi] K scatterings in the region up to about 1 GeV as well as the strong decay [eta]' --&gt; [eta][pi][pi]. At first, one might expect a large enhancement from diagrams including a light [sigma] (560). However there is an amusing cancellation mechanism which prevents this from occurring. In the simplest model there is an enhancement of about 13 per cent in the [eta] -&gt; 3[pi] decay rate due to the scalars. In a more complicated model which includes derivative type symmetry breakers, the cancellation is modified and the scalars contribute about 30 percent of the total decay rate (although the total is not significantly changed). The vectors do not contribute much. Our model produces a reasonable estimate for the related a{sub 0}(980) - f{sub 0}(980) mixing strength, which has been a topic of current debate. Promising directions …
Date: October 1, 2002
Creator: Abdel-Rehim, Abdou; Black, Deirdre; Fariborz, Amir H. & Schechter, Joseph
Object Type: Article
System: The UNT Digital Library