Search Results

open access

Measurement of CP--violating asymmetries in $D^0\to\pi^+\pi^-$ and $D^0\to K^+K^-$ decays at CDF

Description: We report on a measurement of CP-violating asymmetries (A{sub CP}) in the Cabibbo-suppressed D{sup 0} {yields} {pi}{sup +}{pi}{sup -} and D{sup 0} {yields} K{sup +}K{sup -} decays reconstructed in a data sample corresponding to 5.9 fb{sup -1} of integrated luminosity collected by the upgraded Collider Detector at Fermilab. We use the strong decay D*{sup +} {yields} D{sup 0}{pi}{sup +} to identify the flavor of the charmed meson at production and exploit CP-conserving strong c{bar c} pair-produc… more
Date: November 1, 2011
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for high-mass resonances decaying into $ZZ$ in p$\bar{p}$ collisions at $\sqrt{s}=1.96$\,TeV

Description: The authors search for high-mass resonances decaying into Z boson pairs using data corresponding to 6 fb{sup -1} collected by the CDF experiment in p{bar p} collisions at {radical}s = 1.96 TeV. The search is performed in three distinct final states: ZZ {yields} {ell}{sup +}{ell}{sup -}{ell}{sup +}{ell}{sup -}, ZZ {yields} {ell}{sup +}{ell}{sup -}{nu}{nu}, and ZZ {yields} {ell}{sup +}{ell}{sup -}jj. For a Randall-Sundrum graviton G*, the 95% CL upper limits on the production cross section times … more
Date: November 1, 2011
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Partner: UNT Libraries Government Documents Department
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

Description: 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}{… more
Date: November 1, 2007
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Partner: UNT Libraries Government Documents Department
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

Description: 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 pe… more
Date: November 1, 2007
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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 co… more
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.
Partner: UNT Libraries Government Documents Department
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

Description: 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 agree… more
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.
Partner: UNT Libraries Government Documents Department
open access

Rapidity dependence of the inclusive J/{Psi} production in p{bar p} collisions at {radical}s = 1.8 TeV

Description: We have studied J/{psi} production in p{bar p} collisions at {radical}s = 1.8 TeV with the D0 detector at Fermilab, using a {mu}{sup +}{mu}{sup {minus}} data sample collected during the 1994--1995 collider run. We have measured the inclusive J/{psi} production cross section as a function of the J/{psi} transverse momentum, p{sub T}{sup J/{psi}}, in the central and forward rapidity regions. The cross section d{sigma}/dp{sub T}{sup J/{psi}} for {vert_bar}{eta}{sup J/{psi}}{vert_bar}<0.6 covers th… more
Date: November 1, 1995
Creator: Abachi, S.
Partner: UNT Libraries Government Documents Department
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Integrating automatic differentiation with object-oriented toolkits for high-performance scientific computing.

Description: 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 … more
Date: November 1, 2000
Creator: Abate, J.; Benson, S.; Grignon, L.; Hovland, P.; McInnes, L. & Norris, B.
Partner: UNT Libraries Government Documents Department
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An application of robust parameter design using an alternative to Taguchi methods

Description: The factors of interest in designing a product or process can generally be classified into two categories, controllable and uncontrollable. Controllable (or control) factors represent those factors which can be regulated. Examples of control factors include: the choice of material, flow rates, processing pressures, times and temperatures. Uncontrollable (noise) factors are those that are either difficult, impossible or too expensive to control during actual production or use. Examples of noise … more
Date: November 1, 1996
Creator: Abate, M. L.; Morrow, M. C. & Kuczek, T.
Partner: UNT Libraries Government Documents Department
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The Nonlinear cosmological matter power spectrum with massive neutrinos. 1. The Halo model

Description: 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 t… more
Date: November 1, 2004
Creator: Abazajian, Kevork; Alamos, /Los; Switzer, Eric R.; U., /Princeton; Dodelson, Scott; /Fermilab /Chicago U., Astron. Astrophys. Ctr. et al.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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 th… more
Date: November 1, 2007
Creator: Abazov, V. M.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

Determination of the strong coupling constant from the inclusive jet cross section in ppbar collisions at sqrt(s)=1.96 TeV

Description: We determine the strong coupling constant {alpha}{sub s} and its energy dependence from the p{sub T} dependence of the inclusive jet cross section in p{bar p} collisions at {radical}s = 1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50 &lt; p{sub T} &lt; 145 GeV. Using perturbative QCD calculations to order {Omicron}({alpha}{sub s}{sup 3}) combined with {Omicron}({alpha}{sub s}{sup 4}) contributions from threshold corrections, we obtain {alpha}{sub s}(M{… more
Date: November 1, 2009
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV using secondary vertex b tagging

Description: We report a new measurement of the t{bar t} production cross section in p{bar p} collisions at a center-of-mass energy of 1.96 TeV using events with one charged lepton (electron or muon), missing transverse energy, and jets. Using 425 pb{sup -1} of data collected using the D0 detector at the Fermilab Tevatron Collider, and enhancing the t{bar t} content of the sample by tagging b jets with a secondary vertex tagging algorithm, the t{bar t} production cross section is measured to be: {sigma}{sub… more
Date: November 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for sneutrino particles in e + mu final states in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: 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}'{sub 311} and {lambda}{sub 312} as a function of sneutrino mass.
Date: November 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for the pair production of scalar top quarks in the acoplanar charm jet final state in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: A search for the pair production of scalar top quarks, {bar t}, has been performed in 360 pb{sup -1} of data from p{bar p} collisions at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at the Fermilab Tevatron collider. The {bar t} decay mode considered is {bar t} {yields} c{bar {chi}}{sub 1}{sup 0}, where {bar {chi}}{sub 1}{sup 0} is the lightest supersymmetric particle. The topology analyzed therefore consists of a pair of acoplanar heavy-flavor jets with missing transverse … more
Date: November 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for neutral Higgs bosons in the multi-$b$-jet topology in 5.2fb$^{-1}$ of $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV

Description: Data recorded by the D0 experiment at the Fermilab Tevatron Collider are analyzed to search for neutral Higgs bosons produced in association with b quarks. The search is performed in the three-b-quark channel using multijet-triggered events corresponding to an integrated luminosity of 5.2 fb{sup -1}. In the absence of any significant excess above background, limits are set on the cross section multiplied by the branching ratio in the Higgs boson mass range 90 to 300 GeV, extending the excluded … more
Date: November 1, 2010
Creator: Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; U., /Oklahoma; Acharya, Bannanje Sripath; Inst., /Tata et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the W boson helicity in top quark decays using 5.4 fb$^{\boldsymbol{-1}}$ of $\boldsymbol{p\bar{p}}$ collision data

Description: We present a measurement of the helicity of the W boson produced in top quark decays using t{bar t} decays in the {ell}+jets and dilepton final states selected from a sample of 5.4 fb{sup -1} of collisions recorded using the D0 detector at the Fermilab Tevatron p{bar p} collider. We measure the fractions of longitudinal and right-handed W bosons to be f{sub 0} = 0.669 {+-} 0.102 [{+-}0.078 (stat.) {+-} 0.065 (syst.)] and f{sub +} = 0.023 {+-} 0.053 [{+-}0.041 (stat.){+-}0.034 (syst.)], respecti… more
Date: November 1, 2010
Creator: Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Alexeev, Guennadi D. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for resonant WW and WZ production in ppbar collisions at ?s = 1.96 TeV

Description: The standard model of particle physics is expected to be a low energy effective theory valid for particle interactions below the TeV scale. Above this scale, extensions to the standard model (SM) augment the existing particle content, leading to enhanced production of many final states at colliders. Specifically, the production and decay of massive charged or neutral particles can produce an excess of W boson pairs for neutral particles or W and Z boson pairs for charged particles. We search fo… more
Date: November 1, 2010
Creator: Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Alexeev, Guennadi D. et al.
Partner: UNT Libraries Government Documents Department
open access

Higgs-photon associated production at hadron colliders

Description: The authors present cross sections for the reactions p{anti p} {yields} H{gamma} and pp {yields} H{gamma} arising from the subprocess q{anti q} {yields} H{gamma}. The calculation includes the complete one-loop contribution from all light quarks and is the main source of Higgs-photon associated production in hadron colliders. At Tevatron energies, the cross section is typically 0.1 fb or less, while at LHC energies it can exceed 1.0fb.
Date: November 1, 1997
Creator: Abbasabadi, A.; Bowser-Chao, D.; Dicus, D.A. & Repko, W.W.
Partner: UNT Libraries Government Documents Department
open access

Water-related planning and design at energy firms

Description: Water related planning and design at energy firms are examined. By identifying production alternatives and specifying the cost of these alternatives under a variety of conditions, one gains insight into the future pattern of water use in the energy industry and the response of industry to water-related regulation. In Part II, the three principal decisions of industry that affect water allocation are reviewed: where to build plants, where to get water, and how much water to use. The cost of wate… more
Date: November 1, 1980
Creator: Abbey, D & Lucero, F
Partner: UNT Libraries Government Documents Department
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