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Electron-lens test stand instrumentation progress (open access)

Electron-lens test stand instrumentation progress

N/A
Date: October 1, 2012
Creator: A., Miller T.; Aronson, J.; Gassner, D.M.; Gu, X.; Pikin, A. & Thieberger, P.
Object Type: Article
System: The UNT Digital Library
Measurement of the Mass Difference Between Top and Anti-top Quarks at CDF (open access)

Measurement of the Mass Difference Between Top and Anti-top Quarks at CDF

None
Date: October 1, 2012
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Object Type: Article
System: The UNT Digital Library
Top Quark Mass Measurement in the Lepton + Jets Channel Using a Matrix Element Method and \textit{in situ} Jet Energy Calibration (open access)

Top Quark Mass Measurement in the Lepton + Jets Channel Using a Matrix Element Method and \textit{in situ} Jet Energy Calibration

A precision measurement of the top quark mass m{sub t} is obtained using a sample of t{bar t} events from p{bar p} collisions at the Fermilab Tevatron with the CDF II detector. Selected events require an electron or muon, large missing transverse energy, and exactly four high-energy jets, at least one of which is tagged as coming from a b quark. A likelihood is calculated using a matrix element method with quasi-Monte Carlo integration taking into account finite detector resolution and jet mass effects. The event likelihood is a function of m{sub t} and a parameter {Delta}{sub JES} used to calibrate the jet energy scale in situ. Using a total of 1087 events, a value of m{sub t} = 173.0 {+-} 1.2 GeV/c{sup 2} is measured.
Date: October 1, 2010
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Alvarez Gonzalez, B.; Phys., /Cantabria Inst. of; Amerio, S.; /INFN, Padua et al.
Object Type: Article
System: The UNT Digital Library
Precise study of the $Z/\gamma^*$ boson transverse momentum distribution in $p\bar{p}$ collisions using a novel technique (open access)

Precise study of the $Z/\gamma^*$ boson transverse momentum distribution in $p\bar{p}$ collisions using a novel technique

Using 7.3 fb{sup -1} of p{bar p} collisions collected by the D0 detector at the Fermilab Tevatron, we measure the distribution of the variable {phi}*{sub {eta}}, which probes the same physical effects as the Z/{gamma}* boson transverse momentum, but is less susceptible to the effects of experimental resolution and efficiency. A QCD prediction is found to describe the general features of the {phi}*{sub {eta}} distribution, but is unable to describe its detailed shape or dependence on boson rapidity. A prediction that includes a broadening of transverse momentum for small values of the parton momentum fraction is strongly disfavored.
Date: October 1, 2010
Creator: Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; U., /Oklahoma; Abolins, Maris A.; U., /Michigan State et al.
Object Type: Article
System: The UNT Digital Library
A measurement of the ratio of inclusive cross sections $\sigma(p\bar{p}\rightarrow Z+b{\rm\, jet})/ \sigma(p\bar{p}\rightarrow Z+{\rm jet})$ at $\sqrt{s}=1.96$ TeV (open access)

A measurement of the ratio of inclusive cross sections $\sigma(p\bar{p}\rightarrow Z+b{\rm\, jet})/ \sigma(p\bar{p}\rightarrow Z+{\rm jet})$ at $\sqrt{s}=1.96$ TeV

The ratio of the cross section for p{bar p} interactions producing a Z boson and at least one b quark jet to the inclusive Z+jet cross section is measured using 4.2 fb{sup -1} of p{bar p} collisions collected with the D0 detector at the Fermilab Tevatron collider at {radical}s = 1.96 TeV. The Z {yields} {ell}{sup +}{ell}{sup -} candidate events with at least one b jet are discriminated from Z+ charm and light jet(s) events by a novel technique that exploits the properties of the tracks associated to the jet. The measured ratio is 0.0193 {+-} 0.0027 for events having a jet with transverse momentum p{sub T} > 20 GeV and pseudorapidity |{eta}| {le} 2.5, which is the most precise to date and is consistent with theoretical predictions.
Date: October 1, 2010
Creator: Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; U., /Oklahoma; Acharya, Bannanje Sripath; Inst., /Tata et al.
Object Type: Article
System: The UNT Digital Library
Search for single vector-like quarks in $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV (open access)

Search for single vector-like quarks in $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV

We present a search for hypothetical vector-like quarks in p{bar p} collisions at {radical}s = 1.96 TeV. The data were collected by the D0 detector at the Fermilab Tevatron Collider and correspond to an integrated luminosity of 5.4 fb{sup -1}. We select events with a final state composed of a W or Z boson and a jet consistent with a heavy object decay. We observe no significant excess in comparison to the background prediction and set limits on production cross sections for vector-like quarks decaying to W+jet and Z+jet. Assuming a vector-like quark to standard model quark coupling parameter {tilde {kappa}}{sub qQ} of unity, we exclude vector-like quarks with mass below 693 GeV for decays to W+jet and mass below 449 GeV for decays to Z+jet. These are the most stringent mass limits for electroweak single vector-like quark production at hadron colliders.
Date: October 1, 2010
Creator: Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; U., /Oklahoma; Acharya, Bannanje Sripath; Inst., /Tata et al.
Object Type: Article
System: The UNT Digital Library
A Multi-Factor Analysis of Sustainable Agricultural Residue Removal Potential (open access)

A Multi-Factor Analysis of Sustainable Agricultural Residue Removal Potential

Agricultural residues have significant potential as a near term source of cellulosic biomass for bioenergy production, but sustainable removal of agricultural residues requires consideration of the critical roles that residues play in the agronomic system. Previous work has developed an integrated model to evaluate sustainable agricultural residue removal potential considering soil erosion, soil organic carbon, greenhouse gas emission, and long-term yield impacts of residue removal practices. The integrated model couples the environmental process models WEPS, RUSLE2, SCI, and DAYCENT. This study uses the integrated model to investigate the impact of interval removal practices in Boone County, Iowa, US. Residue removal of 4.5 Mg/ha was performed annually, bi-annually, and tri-annually and were compared to no residue removal. The study is performed at the soil type scale using a national soil survey database assuming a continuous corn rotation with reduced tillage. Results are aggregated across soil types to provide county level estimates of soil organic carbon changes and individual soil type soil organic matter content if interval residue removal were implemented. Results show interval residue removal is possible while improving soil organic matter. Implementation of interval removal practices provide greater increases in soil organic matter while still providing substantial residue for bioenergy …
Date: October 1, 2012
Creator: Abodeely, Jared; Muth, David; Adler, Paul; Campbell, Eleanor & Bryden, Kenneth Mark
Object Type: Article
System: The UNT Digital Library
PDF uncertainties at large x and gauge boson production (open access)

PDF uncertainties at large x and gauge boson production

I discuss how global QCD fits of parton distribution functions can make the somewhat separated fields of high-energy particle physics and lower energy hadronic and nuclear physics interact to the benefit of both. In particular, I will argue that large rapidity gauge boson production at the Tevatron and the LHC has the highest short-term potential to constrain the theoretical nuclear corrections to DIS data on deuteron targets necessary for up/down flavor separation. This in turn can considerably reduce the PDF uncertainty on cross section calculations of heavy mass particles such as W' and Z' bosons.
Date: October 1, 2012
Creator: Accardi, Alberto
Object Type: Article
System: The UNT Digital Library
Simulation information regarding Sandia National Laboratories%3CU%2B2019%3E trinity capability improvement metric. (open access)

Simulation information regarding Sandia National Laboratories%3CU%2B2019%3E trinity capability improvement metric.

Sandia National Laboratories, Los Alamos National Laboratory, and Lawrence Livermore National Laboratory each selected a representative simulation code to be used as a performance benchmark for the Trinity Capability Improvement Metric. Sandia selected SIERRA Low Mach Module: Nalu, which is a uid dynamics code that solves many variable-density, acoustically incompressible problems of interest spanning from laminar to turbulent ow regimes, since it is fairly representative of implicit codes that have been developed under ASC. The simulations for this metric were performed on the Cielo Cray XE6 platform during dedicated application time and the chosen case utilized 131,072 Cielo cores to perform a canonical turbulent open jet simulation within an approximately 9-billion-elementunstructured- hexahedral computational mesh. This report will document some of the results from these simulations as well as provide instructions to perform these simulations for comparison.
Date: October 1, 2013
Creator: Agelastos, Anthony Michael & Lin, Paul T.
Object Type: Report
System: The UNT Digital Library
Fully Differential Monte-Carlo Generator Dedicated to TMDs and Bessel-Weighted Asymmetries (open access)

Fully Differential Monte-Carlo Generator Dedicated to TMDs and Bessel-Weighted Asymmetries

We present studies of double longitudinal spin asymmetries in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator, which includes quark intrinsic transverse momentum within the generalized parton model based on the fully differential cross section for the process. Additionally, we apply Bessel-weighting to the simulated events to extract transverse momentum dependent parton distribution functions and also discuss possible uncertainties due to kinematic correlation effects.
Date: October 1, 2013
Creator: Aghasyan, Mher M. & Avakian, Harut A.
Object Type: Article
System: The UNT Digital Library
Ship Effect Neutron Measurements And Impacts On Low-Background Experiments (open access)

Ship Effect Neutron Measurements And Impacts On Low-Background Experiments

The primary particles entering the upper atmosphere as cosmic rays create showers in the atmosphere that include a broad spectrum of secondary neutrons, muons and protons. These cosmic-ray secondaries interact with materials at the surface of the Earth, yielding prompt backgrounds in radiation detection systems, as well as inducing long-lived activities through spallation events, dominated by the higher-energy neutron secondaries. For historical reasons, the multiple neutrons produced in spallation cascade events are referred to as “ship effect” neutrons. Quantifying the background from cosmic ray induced activities is important to low-background experiments, such as neutrino-less double beta decay. Since direct measurements of the effects of shielding on the cosmic-ray neutron spectrum are not available, Monte Carlo modeling is used to compute such effects. However, there are large uncertainties (orders of magnitude) in the possible cross-section libraries and the cosmic-ray neutron spectrum for the energy range needed in such calculations. The measurements reported here were initiated to validate results from Monte Carlo models through experimental measurements in order to provide some confidence in the model results. The results indicate that the models provide the correct trends of neutron production with increasing density, but there is substantial disagreement between the model and experimental …
Date: October 1, 2013
Creator: Aguayo Navarrete, Estanislao; Kouzes, Richard T. & Siciliano, Edward R.
Object Type: Report
System: The UNT Digital Library
Measurement of $\nu_\mu$-Induced Charged-Current Neutral Pion Production Cross Sections on Mineral Oil at $E_\nu\in0.5-2.0$ GeV (open access)

Measurement of $\nu_\mu$-Induced Charged-Current Neutral Pion Production Cross Sections on Mineral Oil at $E_\nu\in0.5-2.0$ GeV

MiniBooNE reports the first absolute cross sections for neutral current single {pi}{sup 0} production on CH{sub 2} induced by neutrino and antineutrino interactions measured from the largest sets of NC {pi}{sup 0} events collected to date. The principal result consists of differential cross sections measured as functions of {pi}{sup 0} momentum and {pi}{sup 0} angle averaged over the neutrino flux at MiniBooNE. We find total cross sections of (4.76 {+-} 0.05{sub stat} {+-} 0.76{sub sys}) x 10{sup -40} cm{sup 2}/nucleon at a mean energy of E{sub {nu}} = 808 MeV and (1.48 {+-} 0.05{sub stat} {+-} 0.23{sub sys}) x 10{sup -40} cm{sup 2}/nucleon at a mean energy of E{sub {nu}} = 664 MeV for {nu}{sub {mu}} and {bar {nu}}{sub {mu}} induced production, respectively. In addition, we have included measurements of the neutrino and antineutrino total cross sections for incoherent exclusive NC 1{pi}{sup 0} production corrected for the effects of final state interactions to compare to prior results.
Date: October 1, 2010
Creator: Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Brice, S. J.; Brown, B. C.; Bugel, L. et al.
Object Type: Article
System: The UNT Digital Library

Modeling and Optimization of Commercial Buildings and Stationary Fuel Cell Systems

This presentation describes the Distributed Generation Building Energy Assessment Tool (DG-BEAT) developed by the National Renewable Energy Laboratory and the University of California Irvine. DG-BEAT is designed to allow stakeholders to assess the economics of installing stationary fuel cell systems in a variety of building types in the United States.
Date: October 1, 2013
Creator: Ainscough, C.; McLarty, D.; Sullivan, R. & Brouwer, J.
Object Type: Presentation
System: The UNT Digital Library
A low-threshold analysis of CDMS shallow-site data (open access)

A low-threshold analysis of CDMS shallow-site data

Data taken during the final shallow-site run of the first tower of the Cryogenic Dark Matter Search (CDMS II) detectors have been reanalyzed with improved sensitivity to small energy depositions. Four {approx}224 g germanium and two {approx}105 g silicon detectors were operated at the Stanford Underground Facility (SUF) between December 2001 and June 2002, yielding 118 live days of raw exposure. Three of the germanium and both silicon detectors were analyzed with a new low-threshold technique, making it possible to lower the germanium and silicon analysis thresholds down to the actual trigger thresholds of {approx}1 keV and {approx}2 keV, respectively. Limits on the spin-independent cross section for weakly interacting massive particles (WIMPs) to elastically scatter from nuclei based on these data exclude interesting parameter space for WIMPs with masses below 9 GeV/c{sup 2}. Under standard halo assumptions, these data partially exclude parameter space favored by interpretations of the DAMA/LIBRA and CoGeNT experiments data as WIMP signals, and exclude new parameter space for WIMP masses between 3 GeV/c{sup 2} and 4 GeV/c{sup 2}.
Date: October 1, 2010
Creator: Akerib, D. S.; Attisha, M. J.; Baudis, L.; Bauer, D. A.; Bolozdynya, A. I.; Brink, P. L. et al.
Object Type: Article
System: The UNT Digital Library
Economic Analysis of a Brackish Water Photovoltaic-Operated (BWRO-PV) Desalination System: Preprint (open access)

Economic Analysis of a Brackish Water Photovoltaic-Operated (BWRO-PV) Desalination System: Preprint

The photovoltaic (PV)-powered reverse-osmosis (RO) desalination system is considered one of the most promising technologies in producing fresh water from both brackish and sea water, especially for small systems located in remote areas. We analyze the economic viability of a small PV-operated RO system with a capacity of 5 m3/day used to desalinate brackish water of 4000 ppm total dissolve solids, which is proposed to be installed in a remote area of the Babylon governorate in the middle of Iraq; this area possesses excellent insolation throughout the year. Our analysis predicts very good economic and environmental benefits of using this system. The lowest cost of fresh water achieved from using this system is US $3.98/ m3, which is very reasonable compared with the water cost reported by small-sized desalination plants installed in rural areas in other parts of the world. Our analysis shows that using this small system will prevent the release annually of 8,170 kg of CO2, 20.2 kg of CO, 2.23 kg of CH, 1.52 kg of particulate matter, 16.41 kg of SO2, and 180 kg of NOx.
Date: October 1, 2010
Creator: Al-Karaghouli, A. & Kazmerski, L. L.
Object Type: Article
System: The UNT Digital Library
Measure Guideline: Basement Insulation Basics (open access)

Measure Guideline: Basement Insulation Basics

This guideline is intended to describe good practices for insulating basements in new and existing homes, and is intended to be a practical resources for building contractors, designers, and also to homeowners.
Date: October 1, 2012
Creator: Aldrich, R.; Mantha, P. & Puttagunta, S.
Object Type: Report
System: The UNT Digital Library
Dairy Analytics and Nutrient Analysis (DANA) Prototype System User Manual (open access)

Dairy Analytics and Nutrient Analysis (DANA) Prototype System User Manual

This document is a user manual for the Dairy Analytics and Nutrient Analysis (DANA) model. DANA provides an analysis of dairy anaerobic digestion technology and allows users to calculate biogas production, co-product valuation, capital costs, expenses, revenue and financial metrics, for user customizable scenarios, dairy and digester types. The model provides results for three anaerobic digester types; Covered Lagoons, Modified Plug Flow, and Complete Mix, and three main energy production technologies; electricity generation, renewable natural gas generation, and compressed natural gas generation. Additional options include different dairy types, bedding types, backend treatment type as well as numerous production, and economic parameters. DANA’s goal is to extend the National Market Value of Anaerobic Digester Products analysis (informa economics, 2012; Innovation Center, 2011) to include a greater and more flexible set of regional digester scenarios and to provide a modular framework for creation of a tool to support farmer and investor needs. Users can set up scenarios from combinations of existing parameters or add new parameters, run the model and view a variety of reports, charts and tables that are automatically produced and delivered over the web interface. DANA is based in the INL’s analysis architecture entitled Generalized Environment for Modeling Systems …
Date: October 1, 2012
Creator: Alessi, Sam & Keiser, Dennis
Object Type: Report
System: The UNT Digital Library
Preparing the Way for New Policy Regarding Adaptation of US Electricity Infrastructure to Climate Change (open access)

Preparing the Way for New Policy Regarding Adaptation of US Electricity Infrastructure to Climate Change

The following pages represent the status of policy regarding adaptation of the electric grid to climate change and proposed directions for new policy development. While strides are being made to understand the current climate and to predict hazards it may present to human systems, both the science and the policy remain at present in an analytical state. The policy proposed in this document involves first continued computational modeling of outcomes which will produce a portfolio of options to be considered in light of specific region-related risks. It is proposed that the modeling continue not only until reasonable policy at various levels of jurisdiction can be derived from its outcome but also on a continuing basis so that as improvements in the understanding of the state and trajectory of climate science along with advancements in technology arise, they can be incorporated into an appropriate and evolving policy.
Date: October 1, 2013
Creator: Allen, Melissa R
Object Type: Report
System: The UNT Digital Library
Extended Operations of the Pratt & Whitney Rocketdyne Pilot-Scale Compact Reformer Year 6 - Activity 3.2 - Development of a National Center for Hydrogen Technology (open access)

Extended Operations of the Pratt & Whitney Rocketdyne Pilot-Scale Compact Reformer Year 6 - Activity 3.2 - Development of a National Center for Hydrogen Technology

U.S. and global demand for hydrogen is large and growing for use in the production of chemicals, materials, foods, pharmaceuticals, and fuels (including some low-carbon biofuels). Conventional hydrogen production technologies are expensive, have sizeable space requirements, and are large carbon dioxide emitters. A novel sorbent-based hydrogen production technology is being developed and advanced toward field demonstration that promises smaller size, greater efficiency, lower costs, and reduced to no net carbon dioxide emissions compared to conventional hydrogen production technology. Development efforts at the pilot scale have addressed materials compatibility, hot-gas filtration, and high-temperature solids transport and metering, among other issues, and have provided the basis for a preliminary process design with associated economics. The process was able to achieve a 93% hydrogen purity on a purge gasfree basis directly out of the pilot unit prior to downstream purification.
Date: October 1, 2011
Creator: Almlie, Jay
Object Type: Report
System: The UNT Digital Library
Test Results and Analysis of LQS03 Third Long Nb3Sn Quadrupole by LARP (open access)

Test Results and Analysis of LQS03 Third Long Nb3Sn Quadrupole by LARP

None
Date: October 1, 2012
Creator: Ambrosio, G.; Andreev, N.; Barzi, E.; Bossert, R.; Buehler, M.; Chlachidze, G. et al.
Object Type: Article
System: The UNT Digital Library
Targeting Net Zero Energy at Fort Carson: Assessment and Recommendations (open access)

Targeting Net Zero Energy at Fort Carson: Assessment and Recommendations

The U.S. Army's Fort Carson installation was selected to serve as a prototype for net zero energy assessment and planning. NREL performed the comprehensive assessment to appraise the potential of Fort Carson to achieve net zero energy status through energy efficiency, renewable energy, and electric vehicle integration. This report summarizes the results of the assessment and provides energy recommendations. This study is part of a larger cross-laboratory effort that also includes an assessment of renewable opportunities at seven other DoD Front Range installations, a microgrid design for Fort Carson critical loads and an assessment of regulatory and market-based barriers to a regional secure smart grid.
Date: October 1, 2011
Creator: Anderson, K.; Markel, T.; Simpson, M.; Leahey, J.; Rockenbaugh, C.; Lisell, L. et al.
Object Type: Report
System: The UNT Digital Library
Conduction Cooling Test of a Splittable Quadrupole for ILC Cryomodules (open access)

Conduction Cooling Test of a Splittable Quadrupole for ILC Cryomodules

None
Date: October 1, 2012
Creator: Andreev, N.; Kashikhin, V. S.; Tartaglia, A.; Kerby, J.; Kimura, N.; Yamamoto, A. et al.
Object Type: Article
System: The UNT Digital Library
First Determination of the Weak Charge of the Proton (open access)

First Determination of the Weak Charge of the Proton

The Qweak experiment has measured the parity-violating asymmetry in polarized e-p elastic scattering at Q^2 = 0.025(GeV/c)^2, employing 145 microamps of 89% longitudinally polarized electrons on a 34.4cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run are reported here, constituting approximately 4% of the data collected in the experiment. From these initial results the measured asymmetry is A_e_p = -279 +- 35 (statistics) +- 31 (systematics) ppb, which is the smallest and most precise asymmetry ever measured in polarized e-p scattering. The small Q^2 of this experiment has made possible the first determination of the weak charge of the proton, Q^p_W, by incorporating earlier parity-violating electron scattering (PVES) data at higher Q^2 to constrain hadronic corrections. The value of Q^p_W obtained in this way is Q^p_W(PVES) = 0.064 +- 0.012, in good agreement with the Standard Model prediction of Q^p_W(SM) = 0.0710 +- 0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q^n_W(PVES+APV) = -0.975 +- 0.010.
Date: October 1, 2013
Creator: Androic, D.; Armstrong, D. S.; Asaturyan, A.; Averett, T.; Balewski, J.; Beaufait, J. et al.
Object Type: Article
System: The UNT Digital Library
Architecture of a Silicon Strip Beam Position Monitor (open access)

Architecture of a Silicon Strip Beam Position Monitor

A collaboration between Fermilab and the Institute for High Energy Physics (IHEP), Beijing, has developed a beam position monitor for the IHEP test beam facility. This telescope is based on 5 stations of silicon strip detectors having a pitch of 60 microns. The total active area of each layer of the detector is about 12 x 10 cm{sup 2}. Readout of the strips is provided through the use of VA1 ASICs mounted on custom hybrid printed circuit boards and interfaced to Adapter Cards via copper-over-kapton flexible circuits. The Adapter Cards amplify and level-shift the signal for input to the Fermilab CAPTAN data acquisition nodes for data readout and channel configuration. These nodes deliver readout and temperature data from triggered events to an analysis computer over gigabit Ethernet links.
Date: October 1, 2010
Creator: Angstadt, R.; Cooper, W.; Demarteau, M.; Green, J.; Jakubowski, S.; Prosser, A. et al.
Object Type: Article
System: The UNT Digital Library