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Plasma Micro-Stability Analysis for the RHIC Electron Beam Cooler (open access)

Plasma Micro-Stability Analysis for the RHIC Electron Beam Cooler

N/A
Date: January 1, 2004
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Cancellation of the Chromatic Effects with proper Field Profile (open access)

Cancellation of the Chromatic Effects with proper Field Profile

N/A
Date: April 1, 2004
Creator: A., Ruggiero
Object Type: Report
System: The UNT Digital Library
Feasibility Study of a 1.5-GeV Proton FFAG in the AGS Tunnel (open access)

Feasibility Study of a 1.5-GeV Proton FFAG in the AGS Tunnel

N/A
Date: June 1, 2004
Creator: A., Ruggiero
Object Type: Report
System: The UNT Digital Library
Using GIS to Identify Remediation Areas in Landfills (open access)

Using GIS to Identify Remediation Areas in Landfills

This paper reports the use of GIS mapping software—ArcMap and ArcInfo Workstation—by the Idaho National Engineering and Environmental Laboratory (INEEL) as a non-intrusive method of locating and characterizing radioactive waste in a 97-acre landfill to aid in planning cleanup efforts. The fine-scale techniques and methods used offer potential application for other burial sites for which hazards indicate a non-intrusive approach. By converting many boxes of paper shipping records in multiple formats into a relational database linked to spatial data, the INEEL has related the paper history to our current GIS technologies and spatial data layers. The wide breadth of GIS techniques and tools quickly display areas in need of remediation as well as evaluate methods of remediation for specific areas as the site characterization is better understood and early assumptions are refined.
Date: August 1, 2004
Creator: A.Tedrow, Linda
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
WasteWater Treatment And Heavy Metals Removal In The A-01 Constructed Wetland 2003 Report (open access)

WasteWater Treatment And Heavy Metals Removal In The A-01 Constructed Wetland 2003 Report

The A-01 wetland treatment system (WTS) was designed to remove metals from the effluent at the A-01 NPDES outfall. The purpose of research conducted during 2003 was to evaluate (1) the ability of the A-01 wetland treatment system to remediate waste water, (2) retention of the removed contaminants in wetland sediment, and (3) the potential remobilization of these contaminants from the sediment into the water column. Surface water and sediment samples were collected and analyzed in this study.
Date: August 1, 2004
Creator: ANNA, KNOX
Object Type: Report
System: The UNT Digital Library
Power Technologies Data Book 2003 Edition (open access)

Power Technologies Data Book 2003 Edition

The 2003 edition of this report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts and comparisons, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, conversion factors, and selected congressional questions and answers.
Date: June 1, 2004
Creator: Aabakken, J.
Object Type: Report
System: The UNT Digital Library
The Nonlinear cosmological matter power spectrum with massive neutrinos. 1. The Halo model (open access)

The Nonlinear cosmological matter power spectrum with massive neutrinos. 1. The Halo model

Measurements of the linear power spectrum of galaxies have placed tight constraints on neutrino masses. We extend the framework of the halo model of cosmological nonlinear matter clustering to include the effect of massive neutrino infall into cold dark matter (CDM) halos. The magnitude of the effect of neutrino clustering for three degenerate mass neutrinos with m{sub v{sub 1}} = 0.9 eV is of order {approx}1%, within the potential sensitivity of upcoming weak lensing surveys. In order to use these measurements to further constrain--or eventually detect--neutrino masses, accurate theoretical predictions of the nonlinear power spectrum in the presence of massive neutrinos will be needed, likely only possible through high-resolution multiple particle (neutrino, CDM and baryon) simulations.
Date: November 1, 2004
Creator: Abazajian, Kevork; Alamos, /Los; Switzer, Eric R.; U., /Princeton; Dodelson, Scott; /Fermilab /Chicago U., Astron. Astrophys. Ctr. et al.
Object Type: Article
System: The UNT Digital Library
First measurement of sigma (p anti-p ---> Z) . Br (Z ---> tau tau) at s**(1/2) = 1.96- TeV (open access)

First measurement of sigma (p anti-p ---> Z) . Br (Z ---> tau tau) at s**(1/2) = 1.96- TeV

The authors present a measurement of the cross section for Z production times the branching fraction to {tau} leptons, {sigma} {center_dot} Br(Z {yields} {tau}{sup +}{tau}{sup -}), in p{bar p} collisions at {radical}s = 1.96 TeV in the channel in which one {tau} decays into {mu}{nu}{sub {mu}}{nu}{sub {tau}}, and the other into hadrons + {nu}{sub {tau}} or e{nu}{sub e}{nu}{sub {tau}}. The data sample corresponds to an integrated luminosity of 226 pb{sup -1} collected with the D0 detector at the Fermilab Tevatron collider. The final sample contains 2008 candidate events with an estimated background of 55%. From this they obtain {sigma} {center_dot} Br(Z {yields} {tau}{sup +}{tau}{sup -}) = 237 {+-} 15(stat) {+-} 18(sys) {+-} 15(lum) pb, in agreement with the standard model prediction.
Date: December 1, 2004
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
A Search for anomalous heavy-flavor quark production in association with W bosons (open access)

A Search for anomalous heavy-flavor quark production in association with W bosons

None
Date: November 1, 2004
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
Search for first-generation scalar leptoquarks in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for first-generation scalar leptoquarks in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors report on a search for pair production of first-generation scalar leptoquarks (LQ) in p{bar p} collisions at {radical}s = 1.96 TeV using an integrated luminosity of 252 pb{sup -1} collected at the Fermilab Tevatron collider by the D0 detector. They observe no evidence for LQ production in the topologies arising from LQ{ovr LQ} {yields} eqeq and LQ{ovr LQ} {yields} eqvq, and derive 95% C.L. lower limits on the LQ mass as a function of {beta}, where {beta} is the branching fraction for LQ {yields} eq. The limits are 241 and 218 GeV/c{sup 2} for {beta} = 1 and 0.5, respectively. These results are combined with those obtained by D0 at {radical}s = 1.8 TeV, which increases these LQ mass limits to 256 and 234 GeV/c{sup 2}.
Date: December 1, 2004
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
A Novel High-Heat Transfer Low-NO{sub x} Natural Gas Combustion System. Final Technical Report (open access)

A Novel High-Heat Transfer Low-NO{sub x} Natural Gas Combustion System. Final Technical Report

A novel high-heat transfer low NO(sub x) natural gas combustion system. The objectives of this program are to research, develop, test, and commercialize a novel high-heat transfer low-NO{sub x} natural gas combustion system for oxygen-, oxygen-enriched air, and air-fired furnaces. This technology will improve the process efficiency (productivity and product quality) and the energy efficiency of high-temperature industrial furnaces by at least 20%. GTI's high-heat transfer burner has applications in high-temperature air, oxygen-enriched air, and oxygen furnaces used in the glass, metals, cement, and other industries. Development work in this program is focused on using this burner to improve the energy efficiency and productivity of glass melting furnaces that are major industrial energy consumers. The following specific project objectives are defined to provide a means of achieving the overall project objectives. (1) Identify topics to be covered, problems requiring attention, equipment to be used in the program, and test plans to be followed in Phase II and Phase III. (2) Use existing codes to develop models of gas combustion and soot nucleation and growth as well as a thermodynamic and parametric description of furnace heat transfer issues. (3) Conduct a parametric study to confirm the increase in process and energy …
Date: January 1, 2004
Creator: Abbasi, H.
Object Type: Report
System: The UNT Digital Library
Colloid-Facilitated Plutonium Transport in Saturated Alluvium (open access)

Colloid-Facilitated Plutonium Transport in Saturated Alluvium

Natural groundwater colloids have been recognized as possible agents for enhancing the subsurface transport of strongly-sorbing radionuclides. To evaluate this mechanism, packed-bed column experiments were conducted comparing the simultaneous transport of dissolved plutonium (Pu), Pu sorbed onto natural colloids, 190-nm and 500-nm diameter fluorescent CML microspheres, and tritiated water in saturated alluvium. Experiments were conducted in two columns having slightly different porosities at two flow rates, resulting in average linear velocities (v{sub z}) of 0.6 to 3.65 cm/hr in one column and 0.57 to 2.85 cm/hr in the other. In all experiments, Pu associated with natural colloids transported through alluvium essentially unretarded, while dissolved Pu was entirely retained. These results were consistent with the strong sorption of Pu to alluvium and the negligible desorption from natural colloids, observed in separate batch experiments, over time scales exceeding those of the column experiments. Breakthroughs of natural colloids preceded tritiated water in all experiments, indicating a slightly smaller effective pore volume for the colloids. The enhancement of colloids transport over tritiated water decreased with v{sub z}, implying {approx} 40% enhancement at v{sub z} = 0. The 500-nm CML microspheres were significantly attenuated in the column experiments compared to the 190-nm microspheres, which exhibited …
Date: June 1, 2004
Creator: Abdel-Fattah, A.; Reimus, P.; Ware, S. & Haga, M.
Object Type: Report
System: The UNT Digital Library
Migration and Entrapment of DNAPLs in Heterogeneous Systems: Impact of Waste and Porous Medium Composition (open access)

Migration and Entrapment of DNAPLs in Heterogeneous Systems: Impact of Waste and Porous Medium Composition

Previously funded EMSP research efforts were directed towards the quantification of dense non-aqueous phase liquid (DNAPL) migration and entrapment behavior in physically and chemically heterogeneous systems. This research demonstrated that chemical heterogeneities can have a significant influence on DNAPL fate and persistence. Previous work, however, was limited to examination of the behavior of pure DNAPLs in systems with simple and well-defined aqueous and solid surface chemistry. The subsurface chemical environments at many DOE sites, however, are generally more complex than these idealized systems, due to the release of complex mixtures of wastes and more complex physical and chemical heterogeneity. The research undertaken in this project seeks to build upon our previous research experience and expertise to explore the influence of waste and porous media composition on DNAPL migration and entrapment in the saturated zone. DNAPL mixtures and soils typical of those found across the DOE complex are being used in these studies. Many of the experimental procedures and protocols used herein are based upon those developed under previous EMSP funding. This past work also provides the conceptual framework for characterizing and interpreting experimental results, mathematical model development, and inverse modeling protocols.
Date: June 1, 2004
Creator: Abriola, Linda M. & Demond, Avery H.
Object Type: Report
System: The UNT Digital Library
A Detailed Chemical Kinetic Analysis of Low Temperature Non-Sooting Diesel Combustion (open access)

A Detailed Chemical Kinetic Analysis of Low Temperature Non-Sooting Diesel Combustion

We have developed a model of the diesel fuel injection process for application to analysis of low temperature non-sooting combustion. The model uses a simplified mixing correlation and detailed chemical kinetics, and analyzes a parcel of fuel as it moves along the fuel jet, from injection into evaporation and ignition. The model predicts chemical composition and soot precursors, and is applied at conditions that result in low temperature non-sooting combustion. Production of soot precursors is the first step toward production of soot, and modeling precursor production is expected to give insight into the overall evolution of soot inside the engine. The results of the analysis show that the model has been successful in describing many of the observed characteristics of low temperature combustion. The model predicts results that are qualitatively similar to those obtained for soot formation experiments at conditions in which the EGR rate is increased from zero to very high values as the fueling rate is kept constant. The model also describes the two paths to achieve non-sooting combustion. The first is smokeless rich combustion and the second is modulated kinetics (MK). The importance of the temperature after ignition and the equivalence ratio at the time of ignition …
Date: October 1, 2004
Creator: Aceves, S M & Flowers, D L
Object Type: Article
System: The UNT Digital Library
Measurement of the cross section for prompt diphoton production in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of the cross section for prompt diphoton production in p anti-p collisions at s**(1/2) = 1.96-TeV

None
Date: December 1, 2004
Creator: Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the J/psi meson and b-hadron production cross sections in p anti-p collisions at s(NN)**(1/2) = 1960-GeV (open access)

Measurement of the J/psi meson and b-hadron production cross sections in p anti-p collisions at s(NN)**(1/2) = 1960-GeV

We present a new measurement of the inclusive and differential production cross sections of J/{psi} mesons and b-hadrons in proton-antiproton collisions at {radical}s = 1960 GeV. The data correspond to an integrated luminosity of 39.7 pb{sup -1} collected by the CDF Run II detector. We find the integrated cross section for inclusive J/{psi} production for all transverse momenta from 0 to 20 GeV/c in the rapidity range |y| < 0.6 to be 4.08 {+-} 0.02(stat){sub -0.33}{sup +0.36}(syst) {mu}b. We separate the fraction of J/{psi} events from the decay of the long-lived b-hadrons using the lifetime distribution in all events with p{sub T} (J/{psi}) > 1.25 GeV/c. We find the total cross section for b-hadrons, including both hadrons and anti-hadrons, decaying to J/{psi} with transverse momenta greater than 1.25 GeV/c in the rapidity range |y(J/{psi})| < 0.6, is 0.330 {+-} 0.005(stat){sub -0.033}{sup +0.036}(syst) {mu}b. Using a Monte Carlo simulation of the decay kinematics of b-hadrons to all final states containing a J/{psi}, we extract the first measurement of the total single b-hadron cross section down to zero transverse momentum at {radical}s = 1960 GeV. We find the total single b-hadron cross section integrated over all transverse momenta for b-hadrons in the …
Date: December 1, 2004
Creator: Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type: Article
System: The UNT Digital Library
Search for anomalous kinematics in t anti-t dilepton events at CDF II (open access)

Search for anomalous kinematics in t anti-t dilepton events at CDF II

None
Date: December 1, 2004
Creator: Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of charged particle multiplicities in gluon and quark jets in proton anti-proton collisions at s**(1/2) = 1.8-TeV (open access)

Measurement of charged particle multiplicities in gluon and quark jets in proton anti-proton collisions at s**(1/2) = 1.8-TeV

The authors report the first model independent measurement of charged particle multiplicities in quark and gluon jets, N{sub q} and N{sub g}, produced at the Tevatron in p{bar p} collisions with center-of-mass energy 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies 41 and 53 GeV by counting charged particle tracks in cones with opening angle of {theta}{sub c} = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = E{sub jet}{theta}{sub c} varies in the range from 12 GeV to 25 GeV. At Q = 19 GeV, the ratio of multiplicities r = N{sub g}/N{sub q} is found to be 1.64 {+-} 0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with re-summed perturbative QCD calculations.
Date: July 1, 2004
Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the W boson polarization in top decay at CDF at s**(1/2) = 1.8-TeV (open access)

Measurement of the W boson polarization in top decay at CDF at s**(1/2) = 1.8-TeV

The polarization of the W boson in t {yields} Wb decay is unambiguously predicted by the Standard Model of electroweak interactions and is a powerful test of our understanding of the tbW vertex. We measure this polarization from the invariant mass of the b quark from t {yields} Wb and the lepton from W {yields} {ell}{nu} whose momenta measure the W decay angle and direction of motion, respectively. In this paper we present a measurement of the decay rate (f{sub V + A}) of the W produced from the decay of the top quark in the hypothesis of V + A structure of the tWb vertex. We find no evidence for the non-standard V + A vertex and set a limit on f{sub V + A} < 0.80 at 95% confidence level. By combining this result with a complementary observable in the same data, we assign a limit on f{sub V + A} < 0.61 at 95% CL. This corresponds to a constraint on the right-handed helicity component of the W polarization of f{sub +} < 0.18 at 95% CL. This limit is the first significant direct constraint on f{sub V + A} in top decay.
Date: November 1, 2004
Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type: Article
System: The UNT Digital Library
Measurements of bottom anti-bottom azimuthal production correlations in proton - anti-proton collisions at s**(1/2) = 1.8-TeV (open access)

Measurements of bottom anti-bottom azimuthal production correlations in proton - anti-proton collisions at s**(1/2) = 1.8-TeV

The authors have measured the azimuthal angular correlation of b{bar b} production, using 86.5 pb{sup -1} of data collected by Collider Detector at Fermilab (CDF) in p{bar p} collisions at {radical}s = 1.8 TeV during 1994-1995. In high-energy p{bar p} collisions, such as at the Tevatron, b{bar b} production can be schematically categorized into three mechanisms. The leading-order (LO) process is ''flavor creation'', where both b and {bar b} quarks substantially participate in the hard scattering and result in a distinct back-to-back signal in final state. The ''flavor excitation'' and the ''gluon splitting'' processes, which appear at next-leading-order (NLO), are known to make a comparable contribution to total b{bar b} cross section, while providing very different opening angle distributions from the LO process. An azimuthal opening angle between bottom and anti-bottom, {Delta}{phi}, has been used for the correlation measurement to probe the interaction creating b{bar b} pairs. The {Delta}{phi} distribution has been obtained from two different methods. one method measures the {Delta}{phi} between bottom hadrons using events with two reconstructed secondary vertex tags. The other method uses b{bar b} {yields} (J/{psi}X)({ell}X') events, where the charged lepton ({ell}) is an electron (e) or a muon ({mu}), to measure {Delta}{phi} between bottom …
Date: December 1, 2004
Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type: Article
System: The UNT Digital Library
{phi} meson production in Au + Au and p + p collisions at {radical}s{sub NN}=200 GeV (open access)

{phi} meson production in Au + Au and p + p collisions at {radical}s{sub NN}=200 GeV

We report the STAR measurement of {psi} meson production in Au + Au and p + p collisions at {radical}s{sub NN} = 200 GeV. Using the event mixing technique, the {psi} spectra and yields are obtained at midrapidity for five centrality bins in Au+Au collisions and for non-singly-diffractive p+p collisions. It is found that the {psi} transverse momentum distributions from Au+Au collisions are better fitted with a single-exponential while the p+p spectrum is better described by a double-exponential distribution. The measured nuclear modification factors indicate that {psi} production in central Au+Au collisions is suppressed relative to peripheral collisions when scaled by the number of binary collisions (<N{sub bin}>). The systematics of <p{sub T}> versus centrality and the constant {psi}/K{sup -} ratio versus beam species, centrality, and collision energy rule out kaon coalescence as the dominant mechanism for {psi} production.
Date: June 1, 2004
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Object Type: Article
System: The UNT Digital Library
Tracing Geothermal Fluids (open access)

Tracing Geothermal Fluids

Geothermal water must be injected back into the reservoir after it has been used for power production. Injection is critical in maximizing the power production and lifetime of the reservoir. To use injectate effectively the direction and velocity of the injected water must be known or inferred. This information can be obtained by using chemical tracers to track the subsurface flow paths of the injected fluid. Tracers are chemical compounds that are added to the water as it is injected back into the reservoir. The hot production water is monitored for the presence of this tracer using the most sensitive analytic methods that are economically feasible. The amount and concentration pattern of the tracer revealed by this monitoring can be used to evaluate how effective the injection strategy is. However, the tracers must have properties that suite the environment that they will be used in. This requires careful consideration and testing of the tracer properties. In previous and parallel investigations we have developed tracers that are suitable from tracing liquid water. In this investigation, we developed tracers that can be used for steam and mixed water/steam environments. This work will improve the efficiency of injection management in geothermal fields, lowering …
Date: March 1, 2004
Creator: Adams, Michael C. & Nash, Greg
Object Type: Report
System: The UNT Digital Library
The 'Road Warrior' for the CDF Online Silicon Vertix Tracker (open access)

The 'Road Warrior' for the CDF Online Silicon Vertix Tracker

None
Date: December 1, 2004
Creator: Adelman, J.; Annovi, A.; Bardi, A.; Belforte, S.; Carosi, R.; Catastini, P. et al.
Object Type: Article
System: The UNT Digital Library