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Plasma Lens for Super Neutrino Beam at BNL and Other Applications (open access)

Plasma Lens for Super Neutrino Beam at BNL and Other Applications

N/A
Date: November 1, 2005
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Analysis and Design of Cold Helium Gas Warm Up for the 2K Experiment (open access)

Analysis and Design of Cold Helium Gas Warm Up for the 2K Experiment

N/A
Date: November 1, 2005
Creator: A., Sidi-Yekhlef; Stohlman, O. & Krupczak, J.
Object Type: Report
System: The UNT Digital Library
Onset and Saturation of Ion Heating by Odd-parity Rotating-magnetic-fields in a Field-reversed Configuration (open access)

Onset and Saturation of Ion Heating by Odd-parity Rotating-magnetic-fields in a Field-reversed Configuration

Heating of figure-8 ions by odd-parity rotating magnetic fields (RMFο) applied to an elongated field-reversed configuration (FRC) is investigated. The largest energy gain occurs at resonances (s ≡ ω(sub)R⁄ω) of the RMFο frequency, ω(sub)R, with the figure-8 orbital frequency, ω, and is proportional to s^2 for s – even resonances and to s for s – odd resonances. The threshold for the transition from regular to stochastic orbits explains both the onset and saturation of heating. The FRC magnetic geometry lowers the threshold for heating below that in the tokamak by an order of magnitude.
Date: November 1, 2005
Creator: A.S. Landsman, S.A. Cohen, A.H. Glasser
Object Type: Article
System: The UNT Digital Library
Quantitative Analysis of Microstructure in Polysiloxanes Using High Resolution Si29 NMR Spectroscopy: Investigation of Lot Variability in the LVM97 and HVM97 PDMS/PDPS Copolymers (open access)

Quantitative Analysis of Microstructure in Polysiloxanes Using High Resolution Si29 NMR Spectroscopy: Investigation of Lot Variability in the LVM97 and HVM97 PDMS/PDPS Copolymers

The quantitative analysis of microstructure and sequence distribution in polysiloxane copolymers using high-resolution solution {sup 29}Si NMR is reported. Copolymers containing dimethylsiloxane (DMS) and diphenysiloxane (DPS) monomer units prepared with either high vinyl content (HVM) or low vinyl content (LVM) were analyzed. The average run length (R{sub exp}), the number average sequence length (l{sub A}, l{sub B}), along with the various linkage probabilities (p{sub AA}, p{sub AB}, p{sub BA}, and p{sub BB}) were determined for different production lots of the LVM97 and HVM97 samples to address the lot variability of microstructure in these materials.
Date: November 1, 2002
Creator: ALAM, TODD M.
Object Type: Report
System: The UNT Digital Library
Spectroscopic Detection of Pathogens (open access)

Spectroscopic Detection of Pathogens

The goal of this LDRD Research project was to provide a preliminary examination of the use of infrared spectroscopy as a tool to detect the changes in cell cultures upon activation by an infectious agent. Due to a late arrival of funding, only 5 months were available to transfer and setup equipment at UTTM,develop cell culture lines, test methods of in-situ activation and collect kinetic data from activated cells. Using attenuated total reflectance (ATR) as a sampling method, live cell cultures were examined prior to and after activation. Spectroscopic data were collected from cells immediately after activation in situ and, in many cases for five successive hours. Additional data were collected from cells activated within a test tube (pre-activated), in both transmission mode as well as in ATR mode. Changes in the infrared data were apparent in the transmission data collected from the pre-activated cells as well in some of the pre-activated ATR data. Changes in the in-situ activated spectral data were only occasionally present due to (1) the limited time cells were studied and (2) incomplete activation. Comparison of preliminary data to infrared bands reported in the literature suggests the primary changes seen are due an increase in ribonucleic …
Date: November 1, 2000
Creator: ALAM,M. KATHLEEN; TIMLIN,JERILYN A.; MARTIN,LAURA E.; HJELLE,DRIAN; LYONS,RICK & GARRISON,KRISTIN
Object Type: Report
System: The UNT Digital Library
QUIET DIRECT SIMULATION OF PLASMAS (open access)

QUIET DIRECT SIMULATION OF PLASMAS

None
Date: November 1, 2001
Creator: ALBRIGHT, B. J.; DAUGHTON, W. & AL, ET
Object Type: Article
System: The UNT Digital Library
Status of the DOE/Sandia Blade Manufacturing Program (open access)

Status of the DOE/Sandia Blade Manufacturing Program

None
Date: November 1, 2000
Creator: ASHWILL,THOMAS D.
Object Type: Article
System: The UNT Digital Library
EXACT SOLUTION OF HEAT CONDUCTION IN A TWO-DOMAIN COMPOSITE CYLINDER WITH AN ORTHOTROPIC OUTER LAYER. (open access)

EXACT SOLUTION OF HEAT CONDUCTION IN A TWO-DOMAIN COMPOSITE CYLINDER WITH AN ORTHOTROPIC OUTER LAYER.

The transient exact solution of heat conduction in a two-domain composite cylinder is developed using the separation of variables technique. The inner cylinder is isotropic and the outer cylindrical layer is orthotropic. Temperature solutions are obtained for boundary conditions of the first and second kinds at the outer surface of the orthotropic layer. These solutions are applied to heat flow calorimeters modeling assuming that there is heat generation due to nuclear reactions in the inner cylinder. Heat flow calorimeter simulations are carried out assuming that the inner cylinder is filled with plutonium oxide powder. The first objective in these simulations is to predict the onset of thermal equilibrium of the calorimeter with its environment. Two types of boundary conditions at the outer surface of the orthotropic layer are used to predict thermal equilibrium. The procedure developed to carry out these simulations can be used as a guideline for the design of calorimeters. Another important application of these solutions is on the estimation of thermophysical properties of orthotropic cylinders. The thermal conductivities in the vertical, radial and circumferential directions of the orthotropic outer layer can be estimated using this exact solution and experimental data. Simultaneous estimation of the volumetric heat capacity …
Date: November 1, 2000
Creator: AVILES-RAMOS, C. & RUDY, C.
Object Type: Article
System: The UNT Digital Library
Measurement of the cross section for W-boson production in association with jets in ppbar collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of the cross section for W-boson production in association with jets in ppbar collisions at s**(1/2) = 1.96-TeV

We present a measurement of the cross section for W-boson production in association with jets in p{bar p} collisions at {radical}s = 1.96 TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb{sup -1} collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W + {ge} n-jet sample (n = 1-4) we measure {sigma}(p{bar p} {yields} W + {ge} n-jet) x {Beta}(W {yields} e{nu}) with respect to the transverse energy E{sub T} of the nth-highest E{sub T} jet above 20 GeV, for a restricted W {yields} e{nu} decay phase space. The cross sections, corrected for all detector effects, can be directly compared to particle level W + jet(s) predictions. We present here comparisons to leading order and next-to-leading order predictions.
Date: November 1, 2007
Creator: Aaltonen, T.
Object Type: Article
System: The UNT Digital Library
Measurement of correlated b-bbar production in p-pbar collisions at s**(1/2) = 1960 GeV (open access)

Measurement of correlated b-bbar production in p-pbar collisions at s**(1/2) = 1960 GeV

We present a measurement of the correlated b{bar b} production cross section. The data used in this analysis were taken with the upgraded CDF detector (CDF II) at the Fermilab Tevatron collider, and correspond to an integrated luminosity of 742 pb{sup -1}. We utilize muon pairs with invariant mass 5 {le} m{sub {mu}{mu}} {le} 80 GeV/c{sup 2} produced by b{bar b} double semileptonic decays. For muons with p{sub T} {ge} 3 GeV/c and |{eta}| {le} 0.7, that are produced by b and {bar b} quarks with p{sub T} {ge} 2 GeV/c and |y| {le} 1.3, we measure {sigma}{sub b{yields}{mu},{bar b}{yields}{mu}} = 1549 {+-} 133 pb. We compare this result with theoretical predictions and previous measurements. We also report the measurement of {sigma}{sub c{yields}{mu},{bar c}{yields}{mu}}, a by-product of the study of the background to b{bar b} production.
Date: November 1, 2007
Creator: Aaltonen, T.; Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G. et al.
Object Type: Article
System: The UNT Digital Library
Inclusive Search for Squark and Gluino Production in p anti-p Collisions at s**(1/2) = 1.96-TeV (open access)

Inclusive Search for Squark and Gluino Production in p anti-p Collisions at s**(1/2) = 1.96-TeV

We report on a search for inclusive production of squarks and gluinos in p{bar p} collisions at {radical}s = 1.96 TeV, in events with large missing transverse energy and multiple jets of hadrons in the final state. The study uses a CDF Run II data sample corresponding to 2 fb-1 of integrated luminosity. The data are in good agreement with the standard model predictions, giving no evidence for any squark or gluino component. In an R-parity conserving minimal supergravity scenario with A{sub 0} = 0, mu < 0 and tan beta = 5, 95% C.L. upper limits on the production cross sections in the range between 0.1 pb and 1 pb are obtained, depending on the squark and gluino masses considered. For gluino masses below 280 GeV/c2, arbitrarily large squark masses are excluded at the 95%C.L., while for mass degenerate gluinos and squarks, masses below 392 GeV/c2 are excluded at the 95% C.L.
Date: November 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 chargino-neutralino production in p anti-p collisions at 1.96-TeV with high-p(T) leptons (open access)

Search for chargino-neutralino production in p anti-p collisions at 1.96-TeV with high-p(T) leptons

The authors present a search for the associated production of charginos and neutralinos in p{bar p} collisions at {radical}s = 1.96 TeV. The data were collected at the Collider Detector at Fermilab (CDF II) and correspond to integrated luminosities between 0.7 and 1.0 fb{sup -1}. They look for final states with one high-p{sub T} electron or muon, and two additional leptons. The results are consistent with the standard model expectations, and they set limits on the cross section as a function of the chargino mass in three different supersymmetric scenarios. For a specific MSSM scenario with no slepton mixing they set a 95% C.L. limit at 151 GeV/c{sup 2}.
Date: November 1, 2007
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
Measurement of the k(T) Distribution of Particles in Jets Produced in p anti-p Collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of the k(T) Distribution of Particles in Jets Produced in p anti-p Collisions at s**(1/2) = 1.96-TeV

We present a measurement of the transverse momentum with respect to the jet axis (k{sub T}) of particles in jets produced in p{bar p} collisions at {radical}s = 1.96 TeV. Results are obtained for charged particles within a cone of opening angle 0.5 radians around the jet axis in events with dijet invariant masses between 66 and 737 GeV/c{sup 2}. The experimental data are compared to theoretical predictions obtained for fragmentation partons within the framework of resummed perturbative QCD using the modified leading log and next-to-modified leading log approximations. The comparison shows that trends in data are successfully described by the theoretical predictions, indicating that the perturbative QCD stage of jet fragmentation is dominant in shaping basic jet characteristics.
Date: November 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of W-Boson Helicity Fractions in Top-Quark Decays Using costheta* (open access)

Measurement of W-Boson Helicity Fractions in Top-Quark Decays Using costheta*

None
Date: November 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the WW+WZ Production Cross Section Using the Lepton+Jets Final State at CDF II (open access)

Measurement of the WW+WZ Production Cross Section Using the Lepton+Jets Final State at CDF II

We report two complementary measurements of the diboson (WW + WZ) cross section in the final state consisting of an electron or muon, missing transverse energy, and jets, performed using p{bar p} collision data at {radical}s = 1.96 TeV collected by the Collider Detector at Fermilab. The first method uses the dijet invariant mass distribution while the second method uses more of the kinematic information in the event through matrix-element calculations of the signal and background processes and has a higher sensitivity. The result from the second method has a signal significance of 5.4{sigma} and is the first observation of WW + WZ production using this signature. Combining the results from both methods gives {sigma}{sub WW+WZ} = 16.0 {+-} 3.3 pb, in agreement with the standard model prediction.
Date: November 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
First measurement of the production of a W boson in association with a single charm quark in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

First measurement of the production of a W boson in association with a single charm quark in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors present the first measurement of the production cross section of a W boson with a single charm quark (c) in p{bar p} collisions at {radical}s = 1.96 TeV, using soft muon tagging of c jets. In a data sample of {approx} 1.8 fb{sup -1}, recorded with the CDF II detector at the Fermilab Tevatron, they select events with W + 1 or 2 jets. They use the charge correlation between the W and the muon from the semileptonic decay of a charm hadron to extract the We signal. They measure {sigma}{sub Wc} (p{sub Tc} > 20 GeV/c, |{eta}{sub c}| < 1.5) x BR(W {yields} {ell}{nu}) = 9.8 {+-} 3.2 pb, in agreement with theoretical expectations.
Date: November 1, 2007
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 inclusive jet cross-sections in Z/gamma*(---> e+ e-) + jets production in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of inclusive jet cross-sections in Z/gamma*(---> e+ e-) + jets production in p anti-p collisions at s**(1/2) = 1.96-TeV

Inclusive jet cross sections in Z/{gamma}* events, with Z/{gamma}* decaying into an electron-positron pair, are measured as a function of jet transverse momentum and jet multiplicity in p{bar p} collisions at {radical}s - 1.96 TeV with the upgraded Collider Detector at Fermilab in Run II, based on an integrated luminosity of 1.7 fb{sup -1}. The measurements cover the rapidity region |y{sup jet}| < 2.1 and the transverse momentum range p{sub T}{sup jet} > 30 GeV/c. Next-to-leading order perturbative QCD predictions are in good agreement with the measured cross sections.
Date: November 1, 2007
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
A search for high-mass resonances decaying to dimuons at CDF (open access)

A search for high-mass resonances decaying to dimuons at CDF

None
Date: November 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
Search for New Color-Octet Vector Particle Decaying to ttbar in ppbar Collisions at $\sqrt{s}=1.96$ TeV (open access)

Search for New Color-Octet Vector Particle Decaying to ttbar in ppbar Collisions at $\sqrt{s}=1.96$ TeV

We present the result of a search for a massive color-octet vector particle, (e.g. a massive gluon) decaying to a pair of top quarks in proton-antiproton collisions with a center-of-mass energy of 1.96 TeV. This search is based on 1.9 fb{sup -1} of data collected using the CDF detector during Run II of the Tevatron at Fermilab. We study t{bar t} events in the lepton+jets channel with at least one b-tagged jet. A massive gluon is characterized by its mass, decay width, and the strength of its coupling to quarks. These parameters are determined according to the observed invariant mass distribution of top quark pairs. We set limits on the massive gluon coupling strength for masses between 400 and 800 GeV/c{sup 2} and width-to-mass ratios between 0.05 and 0.50. The coupling strength of the hypothetical massive gluon to quarks is consistent with zero within the explored parameter space.
Date: November 1, 2009
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Alvarez Gonzalez, B.; Phys., /Cantabria Inst. of et al.
Object Type: Article
System: The UNT Digital Library
A Search for the Higgs Boson Using Neural Networks in Events with Missing Energy and \boldit{b}-quark Jets in $p\bar p$ Collisions at $\sqrt{s}=1.96$ TeV (open access)

A Search for the Higgs Boson Using Neural Networks in Events with Missing Energy and \boldit{b}-quark Jets in $p\bar p$ Collisions at $\sqrt{s}=1.96$ TeV

We report on a search for the standard model Higgs boson produced in association with a W or Z boson in p{bar p} collisions at {radical}s = 1.96 TeV recorded by the CDF II experiment at the Tevatron in a data sample corresponding to an integrated luminosity of 2.1 fb{sup -1}. We consider events which have no identified charged leptons, an imbalance in transverse momentum, and two or three jets where at least one jet is consistent with originating from the decay of a b hadron. We find good agreement between data and predictions. We place 95% confidence level upper limits on the production cross section for several Higgs boson masses ranging from 110 GeV/c{sup 2} to 150 GeV/c{sup 2}. For a mass of 115 GeV/c{sup 2} the observed (expected) limit is 6.9 (5.6) times the standard model prediction.
Date: November 1, 2009
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Alvarez Gonzalez, B.; Phys., /Cantabria Inst. of et al.
Object Type: Article
System: The UNT Digital Library
Integrating automatic differentiation with object-oriented toolkits for high-performance scientific computing. (open access)

Integrating automatic differentiation with object-oriented toolkits for high-performance scientific computing.

Often the most robust and efficient algorithms for the solution of large-scale problems involving nonlinear PDEs and optimization require the computation of derivative quantities. We examine the use of automatic differentiation (AD) to provide code for computing first and second derivatives in conjunction with two parallel numerical toolkits, the Portable, Extensible Toolkit for Scientific Computing (PETSc) and the Toolkit for Advanced Optimization (TAO). We discuss how the use of mathematical abstractions for vectors and matrices in these libraries facilitates the use of AD to automatically generate derivative codes and present performance data demonstrating the suitability of this approach.
Date: November 1, 2000
Creator: Abate, J.; Benson, S.; Grignon, L.; Hovland, P.; McInnes, L. & Norris, B.
Object Type: Article
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
Model-independent measurement of the W boson helicity in top quark decays at D0 (open access)

Model-independent measurement of the W boson helicity in top quark decays at D0

We present the first model-independent measurement of the helicity of W bosons produced in top quark decays, based on a 1 fb{sup -1} sample of candidate t{bar t} events in the dilepton and lepton plus jets channels collected by the D0 detector at the Fermilab Tevatron p{bar p} Collider. We reconstruct the angle {theta}* between the momenta of the down-type fermion and the top quark in the W boson rest frame for each top quark decay. A fit of the resulting cos {theta}* distribution finds that the fraction of longitudinal W bosons f{sub 0} = 0.390 {+-} 0.177 (stat.) {+-} 0.104 (syst.) and the fraction of right-handed W bosons f{sub +} = 0.171 {+-} 0.102 (stat.) {+-} 0.058 (syst.), which is consistent at the 27% C.L. with the standard model.
Date: November 1, 2007
Creator: Abazov, V. M.
Object Type: Article
System: The UNT Digital Library
Search for sneutrino particles in e+mu final states in ppbar collisions at sqrt(s)=1.96 TeV (open access)

Search for sneutrino particles in e+mu final states in ppbar collisions at sqrt(s)=1.96 TeV

We report a search for R-parity violating production and decay of sneutrino particles in the e{mu} final state with 1.04 {+-} 0.06 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron Collider in 2002-2006. Good agreement between the data and the standard model prediction is observed. With no evidence for new physics, we set limits on the R-parity violating couplings {lambda}{prime}{sub 311} and {lambda}{sub 312} as a function of sneutrino mass.
Date: November 1, 2007
Creator: Abazov, V. M.
Object Type: Article
System: The UNT Digital Library