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Abilene Philharmonic Playbill: February 21-April 18, 2009
Program for an Abilene Philharmonic concert that ran from February 21st to April 18th during the 59th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date:
February 2009
Creator:
Abilene Philharmonic
Object Type:
Pamphlet
System:
The Portal to Texas History
Determination of the Parity of the Neutral Pion via the Four-Electron Decay
We present a new determination of the parity of the neutral pion via the double Dalitz decay {pi}{sup 0} {yields} e{sup +}e{sup -}e{sup +}e{sup -}. Our sample, which consists of 30 511 candidate decays, was collected from K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{pi}{sup 0} decays in flight at the KTeV-E799 experiment at Fermi National Accelerator Laboratory. We confirm the negative {pi}{sup 0} parity, and place a limit on scalar contributions to the {pi}{sup 0} {yields} e{sup +}e{sup -}e{sup +}e{sup -} decay amplitude of less than 3.3% assuming CPT conservation. The {pi}{sup 0}{gamma}*{gamma}* form factor is well described by a momentum-dependent model with a slope parameter fit to the final state phase space distribution. Additionally, we have measured the branching ratio of this mode to be B({pi}{sup 0} {yields} e{sup +}e{sup -}e{sup +}e{sup -}) = (3.26 {+-} 0.18) x 10{sup -5}.
Date:
February 1, 2008
Creator:
Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Blucher, E.; Bock, G. J. et al.
Object Type:
Article
System:
The UNT Digital Library
Improved Performance in CuInSe2 and Surface-Modified CuGaSe2 Solar Cells
In this paper, we present an update and review on the progress made in the development of low-bandgap CuInSe2 (CIS) and wide-bandgap CuGaSe2 (CGS) solar cells. Our research project is a primarily concerned with the optimization of the bottom and top cells of the tandem solar cell. This past year, we established new record total-area efficiencies of 15.0% and 10.2% for CIS and surface-modified CGS solar cells, respectively. These achievements were possible by modifying the growth process for CIS and CGS absorbers. We attempt to modify the surface region of the CGS absorber to be CIGS-like in composition. We also have designed a mechanical-stacked tandem solar cell where the 15% CIS cell serves as the bottom cell. The NREL-confirmed total-area efficiency for this tandem device is 15.31%.
Date:
February 1, 2005
Creator:
AbuShama, J.; Noufi, R.; Johnston, S.; Ward, S. & Wu, X.
Object Type:
Article
System:
The UNT Digital Library
EARLY ENTRANCE COPRODUCTION PLANT
The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing Plan (RD and T) for implementation in Phase II. The objective of Phase II is to implement the RD and T as outlined in the Phase I RD and T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing plan …
Date:
February 15, 2001
Creator:
Abughazaleh, John S.; Ahmed, Mushtaq; Anand, Ashok; Anderson, John H.; Benham, Charles; Brent, Fred D. et al.
Object Type:
Report
System:
The UNT Digital Library
Measurement of sigma p anti-p --> Z . Br (Z --> 2tau) in p anti-p collisions at s**(1/2) = 1.96 TeV
We present a measurement of the inclusive production cross-section for Z bosons decaying to tau leptons in p{bar p} collisions at {radical}s = 1.96 TeV. We use a channel with one hadronically-decaying and one electronically-decaying tau. This measurement is based on 350 pb{sup -1} of CDF Run II data. Using a sample of 504 opposite sign e{tau} events with a total expected background of 190 events, we obtain {sigma}(p{bar p} {yields} Z) {center_dot} {Beta}(Z {yields} {tau}{tau}) = 263 {+-} 23(stat) {+-} 14(syst) {+-} 15(lumi) pb, in agreement with the next-to-next-to-leading order QCD prediction. This is the first CDF cross section measurement using hadronically-decaying taus in Run II.
Date:
February 1, 2007
Creator:
Abulencia, A.
Object Type:
Article
System:
The UNT Digital Library
Search for new physics in lepton + photon + X events with 929 pb**(-1) of p anti-p collisions at s**(1/2) = 1.96-TeV
The authors present results of a search at CDF in 929 {+-} 56 pb{sup -1} of p{bar p} collisions at 1.96 TeV for the anomalous production of events containing a high-transverse momentum charged lepton ({ell}, either e or {mu}) and photon ({gamma}), accompanied by missing transverse energy (E{sub T}), and/or additional leptons and photons, and jets (X). They use the same selection criteria as in a previous CDF Run I search, but with an order-magnitude larger data set, a higher p{bar p} collisions energy, and the CDF II detector. They find 163 {ell}{gamma}E{sub T} + X events, compared to an expectation of 150.6 {+-} 13.0 events. They observe 74 {ell}{ell}{gamma} + X events, compared to an expectation of 65.1 {+-} 7.7 events. They find no events similar to the Run II ee{gamma}{gamma}E{sub T} event.
Date:
February 1, 2007
Creator:
Abulencia, A.; /Illinois U., Urbana; Adelman, J.; U., /Chicago; Affolder, T.; /UC, Santa Barbara et al.
Object Type:
Article
System:
The UNT Digital Library
Observation of B0(s) ---> psi(2S)phi and measurement of ratio of branching fractions B(B0(s) ---> psi(2S)phi) / B(B0(s) ---> J/psi phi)
The authors report the first observation of B{sub s}{sup 0} {yields} {psi}(2S){phi} decay in p{bar p} collisions {radical}s = 1.96 TeV using 360 pb{sup -1} of data collected by the CDF II detector at the Fermilab Tevatron. They observe 20.2 {+-} 5.0 and 12.3 {+-} 4.1 B{sub s}{sup 0} {yields} {psi}(2S){phi} candidates, in {psi}(2S) {yields} {mu}{sup +}{mu}{sup -} and {psi}(2S) {yields} J/{psi}{pi}{sup +}{pi}{sup -} decay modes, respectively. They present a measurement of the relative branching fraction {Beta}(B{sub s}{sup 0} {yields} {psi}(2S){phi})/{Beta}(B{sub s}{sup 0} {yields} J/{psi}{phi}) = 0.52 {+-} 0.13(stat.) {+-} 0.04(syst.) {+-} 0.06(BR) using the {psi}(2S) {yields} {mu}{sup +}{mu}{sup -} decay mode.
Date:
February 1, 2006
Creator:
Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, Anthony A.; Akimoto, T.; Albrow, M.G. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for Z' ---> e+ e- using dielectron mass and angular distribution
The authors search Z{prime} bosons in dielectron events produced in p{bar p} collisions at {radical}s = 1.96 TeV, using a 0.45 fb{sup -1} dataset accumulated with the CDF II detector at the Fermilab Tevatron. To identify the Z{prime} {yields} e{sup +}e{sup -} signal, both the dielectron invariant mass distribution and the angular distribution of the electron pair are used. No evidence of a signal is found, and 95% confidence level lower limits are set on the Z{prime} mass for several models. Limits are also placed on the mass and gauge coupling of a generic Z{prime}, as well as on the contact interaction mass scales for different helicity structure scenarios.
Date:
February 1, 2006
Creator:
Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, Anthony A.; Akimoto, T.; Albrow, M.G. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the top quark mass using template methods on dilepton events in p anti-p collisions at s**(1/2) = 1.96-TeV
The authors describe a measurement of the top quark mass from events produced in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using the Collider Detector at Fermilab. They identify t{bar t} candidates where both W bosons from the top quarks decay into leptons (e{nu}, {mu}{nu}, or {tau}{nu}) from a data sample of 360 pb{sup -1}. The top quark mass is reconstructed in each event separately by three different methods, which draw upon simulated distributions of the neutrino pseudorapidity, t{bar t} longitudinal momentum, or neutrino azimuthal angle in order to extract probability distributions for the top quark mass. For each method, representative mass distributions, or templates, are constructed from simulated samples of signal and background events, and parameterized to form continuous probability density functions. A likelihood fit incorporating these parameterized templates is then performed on the data sample masses in order to derive a final top quark mass. Combining the three template methods, taking into account correlations in their statistical and systematic uncertainties, results in a top quark mass measurement of 170.1 {+-} 6.0(stat.) {+-} 4.1(syst.) GeV/c{sup 2}.
Date:
February 1, 2006
Creator:
Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G. et al.
Object Type:
Article
System:
The UNT Digital Library
First Measurement of the Ratio of Central-Electron to Forward-Electron W Partial Cross Sections in p anti-p Collisions at s**(1/2) = 1.96 TeV
We present a measurement of {sigma}(p{bar p} {yields} W) x {Beta}(W {yields} e{nu}) at {radical}s = 1.96 TeV, using electrons identified in the forward region (1.2 < |{eta}| < 2.8) of the CDF II detector. The data correspond to an integrated luminosity of 223 pb{sup -1}. We measure {sigma} x {Beta} = 2796 {+-} 13(stat){sub -90}{sup +95}(syst){+-}162 (lum) pb. Combining this result with a previous CDF measurement obtained using electrons in the central region (|{eta}| {approx}< 1), we present the first measurement of the ratio of central-electron to forward-electron W partial cross sections R{sub exp} = 0.925 {+-} 0.006(stat){+-}0.032(syst), consistent with theoretical predictions using CTEQ and MRST parton distribution functions.
Date:
February 1, 2007
Creator:
Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Instrument, System and Method for Automated Low Cost Atmospheric Measurements
Patent relating to an instrument, system and method for automated low cost atmospheric measurements.
Date:
May 11, 2006
Creator:
Acevedo, Miguel F.; Waller, William T. & Nebgen, Gilbert B.
Object Type:
Patent
System:
The UNT Digital Library
A Comprehensive Study of Surface Chemistry for Application to Engine NOx Aftertreatment
This work focuses on developing a scientific understanding of the processes associated with NO{sub x} trap operation. NO{sub x} traps are the most advanced technology for achieving future emissions standards with diesel engines. Successful development of NO{sub x} traps will allow widespread use of diesel engines in light-duty vehicles, reducing oil imports by as much as 60%. Diesel engines have a high efficiency and low maintenance that makes them the ideal choice for transportation applications. Use of diesel engines in all light-duty vehicles would reduce oil consumption in the USA by 30% and oil imports by 60%, considerably improving our energy security. For heavy trucks, there is no viable alternative to diesel engines. Only diesel engines can provide the necessary high efficiency and long life. These benefits are offset by high emission of pollutants. Diesel engines have high emissions of NO{sub x} and particulate matter. Over the last 20 years, EPA has been reducing allowable emissions from diesel engines, and NO{sub x} emissions are scheduled to be cut by a factor of 10 over the next 7 years. The target NO{sub x} emissions for year 2010 is 0.20 g/hp-hr. This value is well below 1 g/hp-hr, which has been identified …
Date:
February 19, 2004
Creator:
Aceves, S M; Piggot, T; Pitz, W; Mundy, C; Kuo, W & Havstad, M
Object Type:
Report
System:
The UNT Digital Library
Spatial Analysis of Emissions Sources for HCCI Combustion at Low Loads Using a Multi-Zone Model
We have conducted a detailed numerical analysis of HCCI engine operation at low loads to investigate the sources of HC and CO emissions and the associated combustion inefficiencies. Engine performance and emissions are evaluated as fueling is reduced from typical HCCI conditions, with an equivalence ratio f = 0.26 to very low loads (f = 0.04). Calculations are conducted using a segregated multi-zone methodology and a detailed chemical kinetic mechanism for iso-octane with 859 chemical species. The computational results agree very well with recent experimental results. Pressure traces, heat release rates, burn duration, combustion efficiency and emissions of hydrocarbon, oxygenated hydrocarbon, and carbon monoxide are generally well predicted for the whole range of equivalence ratios. The computational model also shows where the pollutants originate within the combustion chamber, thereby explaining the changes in the HC and CO emissions as a function of equivalence ratio. The results of this paper contribute to the understanding of the high emission behavior of HCCI engines at low equivalence ratios and are important for characterizing this previously little explored, yet important range of operation.
Date:
February 20, 2004
Creator:
Aceves, S. M.; Flowers, D. L.; Espinosa-Loza, F.; Martinez-Frias, J.; Dec, J. E.; Sjoberg, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Fuel and Additive Characterization for HCCI Combustion
This paper shows a numerical evaluation of fuels and additives for HCCl combustion. First, a long list of candidate HCCl fuels is selected. For all the fuels in the list, operating conditions (compression ratio, equivalence ratio and intake temperature) are determined that result in optimum performance under typical operation for a heavy-duty engine. Fuels are also characterized by presenting Log(p)-Log(T) maps for multiple fuels under HCCl conditions. Log(p)-Log(T) maps illustrate important processes during HCCl engine operation, including compression, low temperature heat release and ignition. Log(p)-Log(T) diagrams can be used for visualizing these processes and can be used as a tool for detailed analysis of HCCl combustion. The paper also includes a ranking of many potential additives. Experiments and analyses have indicated that small amounts (a few parts per million) of secondary fuels (additives) may considerably affect HCCl combustion and may play a significant role in controlling HCCl combustion. Additives are ranked according to their capability to advance HCCl ignition. The best additives are listed and an explanation of their effect on HCCl combustion is included.
Date:
February 12, 2003
Creator:
Aceves, S. M.; Flowers, D.; Martinez-Frias, J.; Espinosa-Loza, F.; Pitz, W. J. & Dibble, R.
Object Type:
Article
System:
The UNT Digital Library
Transmission System Performance Analysis for High-Penetration Photovoltaics
This study is an assessment of the potential impact of high levels of penetration of photovoltaic (PV) generation on transmission systems. The effort used stability simulations of a transmission system with different levels of PV generation and load.
Date:
February 1, 2008
Creator:
Achilles, S.; Schramm, S. & Bebic, J.
Object Type:
Report
System:
The UNT Digital Library
Genomics-based selection and functional characterization of triterpene glycosyltransferases from the model legume Medicago truncatula
Article on genomics-based selection and functional characterization of triterpene glycosyltransferases from the model legume Medicago truncatula.
Date:
February 2, 2005
Creator:
Achnine, Lahoucine; Huhman, David; Farag, Mohamed A.; Sumner, Lloyd W.; Blount, Jack W. & Dixon, R. A.
Object Type:
Article
System:
The UNT Digital Library
Public Aid and Faith-Based Organizations (Charitable Choice): Background and Selected Legal Issues
None
Date:
February 20, 2002
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
Applying Overseas Missions Strategies Across Town
Lecture given Monday, February 21, 2000, 8:30 AM at Abilene Christian University: "If we can plant growing churches in Latin America, why not get local Spanish evangelistic efforts off and running?"
Date:
February 21, 2000
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
The Nuts and Bolts of Growing Hispanic Works
Lecture given Monday, February 21, 2000, 11:00 AM at Abilene Christian University: "If we can plant growing churches in Latin America, why not get local Spanish evangelistic efforts off and running?"
Date:
February 21, 2000
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
Recovering Spirituality - What 1 Corinthians Really Says About Being Spiritual
Lecture given Tuesday, February 19, 2002, 9:45 AM at Abilene Christian University: "A careful reading of 1 Corinthians reveals Paul's prescription for a church that had spirituality all wrong. We will see that being spiritual has little to do with knowledge and self, and everything to do with community."
Date:
February 19, 2002
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
A Theology for Working with Hispanics
Lecture given Monday, February 21, 2000, 3:30 PM at Abilene Christian University: "If we can plant growing churches in Latin America, why not get local Spanish evangelistic efforts off and running?"
Date:
February 21, 2000
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
Electroweak physics: measurement of the forward-backward charge asymmetry of electron-positron pairs in p anti-p collisions at s**(1/2) = 1.96 tev
We report a measurement of the forward-backward charge asymmetry of electrons from W boson decays in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample of 170 pb{sup -1} collected by the Collider Detector at Fermilab. The asymmetry is measured as a function of electron rapidity and transverse energy and provides new input on the momentum fraction dependence of the u and d quark parton distribution functions within the proton.
Date:
February 23, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Electroweak physics: measurement of w gamma and z gamma production in pp-bar collisions at s**(1/2) = 1.96 tev
The Standard Model predictions for W{gamma} and Z{gamma} production are tested using an integrated luminosity of 200 pb{sup -1} of p{bar p} collision data collected at the Collider Detector at Fermilab. The cross sections are measured by selecting leptonic decays of the W and Z bosons, and photons with transverse energy E{sub T} > 7 GeV that are well separated from leptons. The production cross sections and kinematic distributions for the W{gamma} and Z{gamma} data are compared to SM predictions.
Date:
February 2, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Exotic physics: search for excited and exotic electrons in the e gamma decay channel in p anti-p collisions at s**(1/2) = 1.96 tev
We present a search for excited and exotic electrons (e*) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the CDF II detector. No signal above standard model expectation is seen for associated ee* production. We discuss the e* sensitivity in the parameter space of the excited electron mass M{sub e*} and the compositeness energy scale {Lambda}. In the contact interaction model, we exclude 132 GeV/c{sup 2} < M{sub e*} < 879 GeV/c{sup 2} for {Lambda} = M{sub e*} at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 GeV/c{sup 2} < M{sub e*} < 430 GeV/c{sup 2} at 95% C.L. for the phenomenological coupling f/{Lambda} {approx} 10{sup -2} GeV{sup -1}.
Date:
February 21, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library