The ArgoNeuT experiment (open access)

The ArgoNeuT experiment

ArgoNeuT is a Liquid Argon Time Projection Chamber neutrino experiment that recently completed its physics run in the NuMI beamline at Fermilab. Along with research and design for future LArTPCs, the experiments goals include performing a number of neutrino and anti-neutrino cross section measurements. Also, ArgoNeuT hopes to further the understanding of the nuclear physics involved in neutrino scattering by characterizing the low energy protons created in such interactions.
Date: January 1, 2010
Creator: Spitz, J. & U., /Yale
System: The UNT Digital Library
D0 results on diphoton direct production and double parton interactions in photon + 3 jet events (open access)

D0 results on diphoton direct production and double parton interactions in photon + 3 jet events

We report the measurement of differential diphoton direct production cross sections and a study of photon + 3-jet events with double parton (DP) interactions, based on data taken with the D0 experiment at the Fermilab Tevatron proton-antiproton collider. We measure single differential cross sections as a function of the diphoton mass, the transverse momentum of the diphoton system, the azimuthal angle between the photons, and the polar scattering angle of the photons. In addition, we measure double differential cross sections considering the last three kinematic variables in three diphoton mass bins. The results are compared with different perturbative QCD predictions and event generators. We have used a sample of photon + 3-jet events collected by the D0 experiment with an integrated luminosity of about 1 fb{sup -1} to determine the fraction of events with double parton scattering (f{sub DP}) in a single p{bar p} collision at {radical}s = 1.96 TeV. The DP fraction and effective cross section ({sigma}{sub eff}), a process-independent scale parameter related to the parton density inside the nucleon, are measured in three intervals of the second (ordered in p{sub T}) jet transverse momentum p{sub T}{sup jet2} within the range 15 < p{sub T}{sup jet} < 30 GeV. …
Date: January 1, 2010
Creator: Sawyer, Lee & U., /Louisiana Tech.
System: The UNT Digital Library
B baryon production and decays and B hadron lifetimes (open access)

B baryon production and decays and B hadron lifetimes

In this paper we review the most recent results concerning B Baryons at CDF and D0, including the observation and the study of the properties of the {Omega}{sub b}{sup -}, {Xi}{sub b}{sup -} and {Sigma}{sub b}{sup {+-}(*)}, the observation of new {Lambda}{sub b}{sup 0} decay modes, and a new measurement of the lifetime of the b hadrons in decays with a J/{Psi}. The {Omega}{sub b}{sup -} baryon is observed through the decay chain {Omega}{sub b}{sup -} {yields} J/{Psi}{Omega}{sup -}, where J/{Psi} {yields} {mu}{sup +}{mu}{sup -}, {Omega}{sup -} {yields} {Lambda}K{sup -}, and {Lambda} {yields} pK{sup -}, using 4.2 fb{sup -1} of data. The {Omega}{sub b}{sup -} mass is measured to be 6054.4 {+-} 6.8(stat.) {+-} 0.9(syst.) MeV/c{sup 2}, and the lifetime 1.13{sub -0.40}{sup +0.53}(stat.) {+-} 0.02(syst.) ps. For the {Xi}{sub b}{sup -} the mass is measured 5790.9 {+-} 2.6(stat.) {+-} 0.8(syst.) MeV/c{sup 2} and the lifetime 1.56{sub -0.25}{sup +0.27}(stat.) {+-} 0.02(syst.) ps. A new accurate measurement of the properties of the resonances {Sigma}{sub b}{sup +}, {Sigma}{sub b}{sup -}, {Sigma}*{sub b}{sup +}, and {Sigma}*{sub b}{sup -} has been performed in 6 fb{sup -1} of data, and the masses have been determined, m({Sigma}{sub b}{sup +}) = 5811.2{sub -0.8}{sup +0.9}(stat.) {+-} 1.7(syst.), m({Sigma}{sub b}{sup …
Date: January 1, 2010
Creator: Donati, S.
System: The UNT Digital Library
Surface characterizatin of palladium-alumina sorbents for high-temperature capture of mercury and arsenic from fuel gas (open access)

Surface characterizatin of palladium-alumina sorbents for high-temperature capture of mercury and arsenic from fuel gas

Coal gasification with subsequent cleanup of the resulting fuel gas is a way to reduce the impact of mercury and arsenic in the environment during power generation and on downstream catalytic processes in chemical production, The interactions of mercury and arsenic with PdlAl2D3 model thin film sorbents and PdlAh03 powders have been studied to determine the relative affinities of palladium for mercury and arsenic, and how they are affected by temperature and the presence of hydrogen sulfide in the fuel gas. The implications of the results on strategies for capturing the toxic metals using a sorbent bed are discussed.
Date: January 1, 2010
Creator: Baltrus, J. P.; Granite, E. J.; Pennline, H. W.; Stanko, D.; Hamilton, H.; Rowsell, L. et al.
System: The UNT Digital Library
Measuring the flavor asymmetry in the sea quarks of the proton (open access)

Measuring the flavor asymmetry in the sea quarks of the proton

The proton is a composite object made of fundamental, strongly-interacting quarks. Many of the features of the proton can be described by a simple picture based on three valence quarks bound by the exchange of gluons. However, protons are much more complex objects with the vast majority of their mass dynamically generated by Quantum Chromodynamics (QCD). This mass manifests itself through a 'sea' of gluons and quark-antiquark pairs. By measuring Drell-Yan scattering, the Fermilab E-906/SeaQuest experiment will study the sea quark distribution in the proton and, in particular, the unusually large asymmetry between anti-up and anti-down quarks measured by earlier Drell-Yan experiments. This asymmetry cannot simply be generated through pair creation, but rather indicates an underlying, fundamental antiquark component in the proton. Using the same technique, E-906/SeaQuest will also investigate the differences between the antiquark distributions of the free proton and a proton bound in a nucleus. Nuclear binding is expected to modify the quark distributions and it has long been known that the overall quark distributions are different (the EMC effect). Surprisingly, present data suggests that the antiquark distributions and hence the sea distributions are not modified. To accomplish these goals, the experiment will used a 120 GeV proton …
Date: January 1, 2010
Creator: Reimer, Paul E.
System: The UNT Digital Library
The QCD Phase Diagram: Large Nc, Quarkyonic Matter and the Triple Point (open access)

The QCD Phase Diagram: Large Nc, Quarkyonic Matter and the Triple Point

I discuss the phase diagram of QCD in the large N_c limit. Quarkyonic Matter is described. The properties of QCD matter as measured in the abundance of produced particles are shown to be consistent with this phase diagram. A possible triple point of Hadronic Mater, Deconfined Matter and Quarkyonic matter is shown to explain various behaviors of ratios of particles abundances seen in CERN fixed target experiments.
Date: January 31, 2010
Creator: McLerran, L.
System: The UNT Digital Library
Pediatric Healthcare Response to Pandemic (H1N1) 2009 Influenza Stakeholder Meeting - Summary of Proceedings (open access)

Pediatric Healthcare Response to Pandemic (H1N1) 2009 Influenza Stakeholder Meeting - Summary of Proceedings

The goal of the meeting was to bring together subject matter experts to develop tools and resources for use by the pediatric healthcare community in response to 2009 (H1N1) pandemic influenza activity during the 2009 influenza season.
Date: January 1, 2010
Creator: CHE, HCTT
System: The UNT Digital Library
Planning Guide for Vaccinating Pediatric Patients Against H1N1 Influenza in Private Healthcare Settings (open access)

Planning Guide for Vaccinating Pediatric Patients Against H1N1 Influenza in Private Healthcare Settings

The purpose of this document is to provide guidance for planning and conducting 2009 H1N1 Influenza vaccination of pediatric patients in private healthcare settings.
Date: January 1, 2010
Creator: CHE, HCTT
System: The UNT Digital Library
Latest results from the MINOS experiment (open access)

Latest results from the MINOS experiment

The MINOS experiment utilizes the NuMI neutrino beam to study the phenomenon of neutrino oscillations. Muon neutrinos are sent over a baseline of 735 km, with a detector near the production point at Fermilab and one at the Soudan underground laboratory in northern Minnesota. By observing the {nu}{sub {mu}} disappearance characteristic of oscillations, MINOS can measure the oscillation parameters. MINOS has previously made the best measurement of the atmospheric-regime mass splitting to date. New results are presented in which the data-set is doubled. Further analysis improvements, and the inclusion of additional event samples, further improve the sensitivity to the oscillation parameters. The mixing angle {theta}{sub 13} is currently not measured to differ from zero. By searching for {nu}{sub e} appearance in the {nu}{sub {mu}} beam, MINOS is able to set new limits on the value of {theta}{sub 13}. An observation of the neutral current interaction rate at the far detector allows limits to be placed on the existence of sterile neutrinos. From September 2009 to March 2010, MINOS has taken data with a dedicated {bar {nu}}{sub {mu}} beam, allowing the first direct precision measurement of the antineutrino oscillation parameters in the atmospheric regime.
Date: January 1, 2010
Creator: Evans, Justin & London, /University Coll.
System: The UNT Digital Library
Standard model high mass Higgs search at CDF (open access)

Standard model high mass Higgs search at CDF

The CDF collaboration has analyzed almost 6 f b{sup -1} of data collected at the Tevatron Collider at {radical}{ovr s} = 1.96 TeV to search for Standard Model Higgs boson through the decay into W{sup +}W{sup -}*. Starting from events with two leptons, advanced analysis techniques are applied to better discriminate signal from background. The Higgs sensitivity is maximized combining together analysis that exploit different event topologies. No significant excess over the expected background is observed and data is used to set a limit in units of Standard Model expectations. The limit plays a fundamental role in the Higgs search excluding the existence of this particle with mass between 158 and 175 GeV/c{sup 2} when combined with D0, the other Tevatron experiment.
Date: January 1, 2010
Creator: Lucchesi, Donatella
System: The UNT Digital Library
Measurement of Interfacial Area Production and Permeability within Porous Media (open access)

Measurement of Interfacial Area Production and Permeability within Porous Media

An understanding of the pore-level interactions that affect multi-phase flow in porous media is important in many subsurface engineering applications, including enhanced oil recovery, remediation of dense non-aqueous liquid contaminated sites, and geologic CO2 sequestration. Standard models of two-phase flow in porous media have been shown to have several shortcomings, which might partially be overcome using a recently developed model based on thermodynamic principles that includes interfacial area as an additional parameter. A few static experimental studies have been previously performed, which allowed the determination of static parameters of the model, but no information exists concerning the interfacial area dynamic parameters. A new experimental porous flow cell that was constructed using stereolithography for two-phase gas-liquid flow studies was used in conjunction with an in-house analysis code to provide information on dynamic evolution of both fluid phases and gas-liquid interfaces. In this paper, we give a brief introduction to the new generalized model of two-phase flow model and describe how the stereolithography flow cell experimental setup was used to obtain the dynamic parameters for the interfacial area numerical model. In particular, the methods used to determine the interfacial area permeability and production terms are shown.
Date: January 1, 2010
Creator: Crandall, Dustin; Ahmadi, Goodarz & Smith, Duane H.
System: The UNT Digital Library
Heat Pipe Embedded AlSiC Plates for High Conductivity - Low CTE Heat Spreaders (open access)

Heat Pipe Embedded AlSiC Plates for High Conductivity - Low CTE Heat Spreaders

Heat pipe embedded aluminum silicon carbide (AlSiC) plates are innovative heat spreaders that provide high thermal conductivity and low coefficient of thermal expansion (CTE). Since heat pipes are two phase devices, they demonstrate effective thermal conductivities ranging between 50,000 and 200,000 W/m-K, depending on the heat pipe length. Installing heat pipes into an AlSiC plate dramatically increases the plate’s effective thermal conductivity. AlSiC plates alone have a thermal conductivity of roughly 200 W/m-K and a CTE ranging from 7-12 ppm/ deg C, similar to that of silicon. An equivalent sized heat pipe embedded AlSiC plate has effective thermal conductivity ranging from 400 to 500 W/m-K and retains the CTE of AlSiC.
Date: January 7, 2010
Creator: Johnson, Matthew; Weyant, J.; Garner, S. & Occhionero, M.
System: The UNT Digital Library
Minimum bias and underlying event studies at CDF (open access)

Minimum bias and underlying event studies at CDF

Soft, non-perturbative, interactions are poorly understood from the theoretical point of view even though they form a large part of the hadronic cross section at the energies now available. We review the CDF studies on minimum-bias ad underlying event in p{bar p} collisions at 2 TeV. After proposing an operative definition of 'underlying event', we present part of a systematic set of measurements carried out by the CDF Collaboration with the goal to provide data to test and improve the QCD models of hadron collisions. Different analysis strategies of the underlying event and possible event topologies are discussed. Part of the CDF minimum-bias results are also presented: in this sample, that represent the full inelastic cross-section, we can test simultaneously our knowledge of all the components that concur to form hadronic interactions. Comparisons with MonteCarlo simulations are always shown along with the data. These measurements will also contribute to more precise estimates of the soft QCD background of high-p{sub T} observables.
Date: January 1, 2010
Creator: Moggi, Niccolo & /INFN, Bologna
System: The UNT Digital Library
Search for new physics in the dijet mass spectrum and dijet ratio in p p collisions at s**(1/2) = 7-TeV (open access)

Search for new physics in the dijet mass spectrum and dijet ratio in p p collisions at s**(1/2) = 7-TeV

A search for new Physics is performed with inclusive dijet final states in pp collisions, using data corresponding to an integrated luminosity of 120 {+-} 13 nb{sup -1} collected by the CMS experiment at LHC. Generic upper limits at the 95% confidence level (CL) are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% CL: string resonances, with mass less than 1.67 TeV, excited quarks, with mass less than 0.59 TeV and axigluons and colorons with mass less than 0.52 TeV. A search for quark compositeness in the form of quark contact interactions is conducted using the dijet centrality ratio, which quantifies the angular distribution of the dijets. The measurement is found to agree with the predictions of the Standard Model and the statistical analysis of the data provides a lower limit on the energy scale of quark contact interactions of 1.9 TeV at the 95% confidence level. The above results extend previously published limits on these models.
Date: January 1, 2010
Creator: Kousouris, Konstantinos
System: The UNT Digital Library
Measurement of W and Z properties at the Tevatron (open access)

Measurement of W and Z properties at the Tevatron

The very large sample of proton-antiproton data collected at the Tevatron at {radical}s = 1.96 TeV, allows the two full purpose experiment CDF and D0 to study in detail the properties of W and Z bosons and to exploit them to study high-energy interactions. The very large samples of vector bosons allow also accurate measurement of S.M. parameters which help constrain models of new physics. Last but not least, the W mass, related to the EWSB sector, can help in the long lasting search for the Higgs particle.
Date: January 1, 2010
Creator: Chiarelli, Giorgio
System: The UNT Digital Library
Summary report of working group 5: Beam and radiation generation, monitoring, and control (open access)

Summary report of working group 5: Beam and radiation generation, monitoring, and control

This paper summarizes the activities and presentations of Working Group 5 of the Advanced Accelerator Concepts Workshop held at Annapolis, Maryland in June 2010. Working Group 5 touched on a broad range of topics in the fields of beam and radiation generation and their monitoring and control. These topics were not comprehensively covered in this Workshop, but rather the Working Group concentrated on specific new developments and recent investigations. The Working Group divided its sessions into four broad categories: cathodes and electron guns, radiation generation, beam diagnostics, and beam control and dynamics. This summary is divided into the same structure.
Date: January 1, 2010
Creator: Church, Mike & Kim, Ki-Yong
System: The UNT Digital Library
Measurement of the top quark mass at D0 (open access)

Measurement of the top quark mass at D0

The most recent measurements of the mass of the quark top at D0 are reviewed. The analysis methods include the direct measurement by Matrix Element and Weighting method and the indirect measurement from t{bar t} production cross section. They have been applied on different experimental signatures, all including at least one electron or muon. Measurements include from 1 to 3.6 fb{sup -1} of D0 data. The most recent combination of mass measurements from D0 and from CDF are also quoted.
Date: January 1, 2010
Creator: Petrillo, Gianluca
System: The UNT Digital Library
Terrestrial biogeochemical feedbacks in the climate system: from past to future (open access)

Terrestrial biogeochemical feedbacks in the climate system: from past to future

The terrestrial biosphere plays a major role in the regulation of atmospheric composition, and hence climate, through multiple interlinked biogeochemical cycles (BGC). Ice-core and other palaeoenvironmental records show a fast response of vegetation cover and exchanges with the atmosphere to past climate change, although the phasing of these responses reflects spatial patterning and complex interactions between individual biospheric feedbacks. Modern observations show a similar responsiveness of terrestrial biogeochemical cycles to anthropogenically-forced climate changes and air pollution, with equally complex feedbacks. For future conditions, although carbon cycle-climate interactions have been a major focus, other BGC feedbacks could be as important in modulating climate changes. The additional radiative forcing from terrestrial BGC feedbacks other than those conventionally attributed to the carbon cycle is in the range of 0.6 to 1.6 Wm{sup -2}; all taken together we estimate a possible maximum of around 3 Wm{sup -2} towards the end of the 21st century. There are large uncertainties associated with these estimates but, given that the majority of BGC feedbacks result in a positive forcing because of the fundamental link between metabolic stimulation and increasing temperature, improved quantification of these feedbacks and their incorporation in earth system models is necessary in order to develop …
Date: January 5, 2010
Creator: Arneth, A.; Harrison, S. P.; Zaehle, S.; Tsigaridis, K.; Menon, S.; Bartlein, P. J. et al.
System: The UNT Digital Library
Precision measurements of the top quark mass and width with the D0 detector (open access)

Precision measurements of the top quark mass and width with the D0 detector

Since the discovery of the top quark in 1995 at the Fermliab Tevatron Collider, top quark properties have been measured with ever higher precision. In this article, recent measurements of the top quark mass and its width using up to 3.6 fb{sup -1} of D0 data are summarized. Different techniques and final states have been examined and no deviations within these measurements have been observed. In addition to the direct measurements, a measurement of the top quark mass from its production cross section and a measurement of the top-antitop quark mass difference are discussed. With a mass of 173.3 {+-} 1.1 GeV, the top quark is the heaviest of all known fundamental particles. Due to the high mass, its Yukawa coupling is close to unity suggesting that it may play a special role in electroweak symmetry breaking. Precise measurements of both, the W boson and the top quark mass, constrain the mass of the yet unobserved Higgs boson and allow to restrict certain extensions of the Standard Model. At the Tevatron collider with a center-of-mass energy of 1.96 TeV, 85% of the top quark pairs are produced in quark-antiquark annihilation; 15% originate from gluon fusion. Top quarks are predicted to …
Date: January 1, 2010
Creator: Grohsjean, Alexander & /IRFU, SPP, Saclay
System: The UNT Digital Library
The Neutral kaon mixing parameter B(K) from unquenched mixed-action lattice QCD (open access)

The Neutral kaon mixing parameter B(K) from unquenched mixed-action lattice QCD

We calculate the neutral kaon mixing parameter B{sub K} in unquenched lattice QCD using asqtad-improved staggered sea quarks and domain-wall valence quarks. We use the '2+1' flavor gauge configurations generated by the MILC Collaboration, and simulate with multiple valence and sea quark masses at two lattice spacings of a {approx} 0.12 fm and a {approx} 0.09 fm. We match the lattice determination of B{sub K} to the continuum value using the nonperturbative method of Rome-Southampton, and extrapolate B{sub K} to the continuum and physical quark masses using mixed action chiral perturbation theory. The 'mixed-action' method enables us to control all sources of systematic uncertainty and therefore to precisely determine B{sub K}; we find a value of B{sub K}{sup {ovr MS},NDR} (2 GeV) = 0.527(6)(21), where the first error is statistical and the second is systematic.
Date: January 1, 2010
Creator: Christopher Aubin, Jack Laiho, Ruth S. Van de Water
System: The UNT Digital Library
Thermal single-well injection-withdrawal tracer tests for determining fracture-matrix heat transfer area (open access)

Thermal single-well injection-withdrawal tracer tests for determining fracture-matrix heat transfer area

Single-well injection-withdrawal (SWIW) tracer tests involve injection of traced fluid and subsequent tracer recovery from the same well, usually with some quiescent time between the injection and withdrawal periods. SWIW are insensitive to variations in advective processes that arise from formation heterogeneities, because upon withdrawal, fluid parcels tend to retrace the paths taken during injection. However, SWIW are sensitive to diffusive processes, such as diffusive exchange of conservative or reactive solutes between fractures and rock matrix. This paper focuses on SWIW tests in which temperature itself is used as a tracer. Numerical simulations demonstrate the sensitivity of temperature returns to fracture-matrix interaction. We consider thermal SWIW response to the two primary reservoir improvements targeted with stimulation, (1) making additional fractures accessible to injected fluids, and (2) increasing the aperture and permeability of pre-existing fractures. It is found that temperature returns in SWIW tests are insensitive to (2), while providing a strong signal of more rapid temperature recovery during the withdrawal phase for (1).
Date: January 15, 2010
Creator: Pruess, K. & Doughty, C.
System: The UNT Digital Library
Higgs searches at the Tevatron (open access)

Higgs searches at the Tevatron

We present the latest results on searches for the standard and beyond-the-standard model Higgs bosons in proton-antiproton collisions at {radical}s = 1.96 TeV by the CDF and D0 experiments at the Fermilab Tevatron. No significant excess is observed above the expected background, and the cross section limits for the Higgs bosons are calculated. It is noticed that the standard model Higgs boson in the mass range 163-166 GeV/c{sup 2} is excluded at the 95% C.L.
Date: January 1, 2010
Creator: Yamamoto, Kazuhiro & U., /Osaka City
System: The UNT Digital Library
Pandemic Influenza Pediatric Office Plan Template (open access)

Pandemic Influenza Pediatric Office Plan Template

This is a planning tool developed by pediatric stakeholders that is intended to assist pediatric medical offices that have no pandemic influenza plan in place, but may experience an increase in patient calls/visits or workload due to pandemic influenza.
Date: January 1, 2010
Creator: CHE, HCTT
System: The UNT Digital Library
$W/Z$ + jets results from CDF (open access)

$W/Z$ + jets results from CDF

The CDF Collaboration has a comprehensive program of studying the production of vector bosons, W and Z, in association with energetic jets. Excellent understanding of the standard model W/Z+jets and W/Z+c,b-jets processes is of paramount importance for the top quark physics and for the Higgs boson and many new physics searches. We review the latest CDF results on Z-boson production in association with inclusive and b-quark jets, study of the p{sub T} balance in Z+jet events, and a measurement of the W+charm production cross section. The results are based on 4-5 fb{sup -1} of data and compared to various Monte Carlo and next-to-leading order perturbative QCD predictions.
Date: January 1, 2010
Creator: Camarda, Stefano
System: The UNT Digital Library