SwePub - search: WFRF:(Fox I)

Enumeration	Reference	Cover	Find
1.	Calabresi, PA, et al. (author) The incidence and significance of anti-natalizumab antibodies: results from AFFIRM and SENTINEL 2007 In: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 1526-632X .- 0028-3878. ; 69:14, s. 1391-1403 Journal article (peer-reviewed)
2.	Yusuf, S, et al. (author) Comparison of fondaparinux and enoxaparin in acute coronary syndromes 2006 In: The New England journal of medicine. - 1533-4406 .- 0028-4793. ; 354:14, s. 1464-1476 Journal article (peer-reviewed)
3.	Fox, Z, et al. (author) Predictors of CD4 count change over 8 months of follow up in HIV-1-infected patients with a CD4 count>or=300 cells/microL who were assigned to 7.5 MIU interleukin-2 2007 In: HIV medicine. - : Wiley. - 1464-2662 .- 1468-1293. ; 8:2, s. 112-123 Journal article (peer-reviewed)
4.	Adare, A., et al. (author) System size and energy dependence of jet-induced hadron pair correlation shapes in Cu+Cu and Au+Au collisions at root S-NN 200 and 62.4 GeV 2007 In: Physical Review Letters. - 1079-7114. ; 98:23 Journal article (peer-reviewed)abstract We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from dijets in Cu+Cu and Au+Au collisions at root s(NN)=62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from Delta phi=pi in central and semicentral collisions in all the systems. The broadening and peak location are found to depend upon the number of participants in the collision, but not on the collision energy or beam nuclei. These results are consistent with sound or shock wave models, but pose challenges to Cherenkov gluon radiation models.
5.	Abdesselam, A., et al. (author) The ATLAS semiconductor tracker end-cap module 2007 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 575:3, s. 353-389 Journal article (peer-reviewed)abstract The challenges for the tracking detector systems at the LHC are unprecedented in terms of the number of channels, the required read-out speed and the expected radiation levels. The ATLAS Semiconductor Tracker. (SCT) end-caps have a total of about 3 million electronics channels each reading out every 25 ns into its own on-chip 3.3 mu s buffer. The highest anticipated dose after 10 years operation is 1.4x10(14) cm(-2) in units of 1 MeV neutron equivalent (assuming the damage factors scale with the non-ionising energy loss). The forward tracker has 1976 double-sided modules, mostly of area similar to 70 cm(2), each having 2 x 768 strips read out by six ASICs per side. The requirement to achieve an average perpendicular radiation length of 1.5% X-0, while coping with up to 7 W dissipation per module (after irradiation), leads to stringent constraints on the thermal design. The additional requirement of 1500e(-) equivalent noise charge (ENC) rising to only 1800e(-) ENC after irradiation, provides stringent design constraints on both the high-density Cu/Polyimide flex read-out circuit and the ABCD3TA read-out ASICs. Finally, the accuracy of module assembly must not compromise the 16 mu m (r phi) resolution perpendicular to the strip directions or 580 mu m radial resolution coming from the 40 mrad front-back stereo angle. A total of 2210 modules were built to the tight tolerances and specifications required for the SCT. This was 234 more than the 1976 required and represents a yield of 93%. The component flow was at times tight, but the module production rate of 40-50 per week was maintained despite this. The distributed production was not found to be a major logistical problem and it allowed additional flexibility to take advantage of where the effort was available, including any spare capacity, for building the end-cap modules. The collaboration that produced the ATLAS SCT end-cap modules kept in close contact at all times so that the effects of shortages or stoppages at different sites could be rapidly resolved.
6.	Adare, A., et al. (author) Charged hadron multiplicity fluctuations in Au plus Au and Cu plus Cu collisions from s(NN)=22.5 to 200 GeV 2008 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:4 Journal article (peer-reviewed)abstract A comprehensive survey of event-by-event fluctuations of charged hadron multiplicity in relativistic heavy ions is presented. The survey covers Au+Au collisions at s(NN)=62.4 and 200 GeV, and Cu+Cu collisions at s(NN)=22.5,62.4, and 200 GeV. Fluctuations are measured as a function of collision centrality, transverse momentum range, and charge sign. After correcting for nondynamical fluctuations due to fluctuations in the collision geometry within a centrality bin, the remaining dynamical fluctuations expressed as the variance normalized by the mean tend to decrease with increasing centrality. The dynamical fluctuations are consistent with or below the expectation from a superposition of participant nucleon-nucleon collisions based upon p+p data, indicating that this dataset does not exhibit evidence of critical behavior in terms of the compressibility of the system. A comparison of the data with a model where hadrons are independently emitted from a number of hadron clusters suggests that the mean number of hadrons per cluster is small in heavy ion collisions.
7.	Adare, A., et al. (author) Cold nuclear matter effects on J/psi production as constrained by deuteron-gold measurements at root S-NN=200 GeV 2008 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 77:2, s. 15-024912 Journal article (peer-reviewed)abstract We present a new analysis of J/psi production yields in deuteron-gold collisions at root s(NN) =200 GeV using data taken from the PHENIX experiment in 2003 and previously published in S. S. Adler [Phys. Rev. Lett 96, 012304 (2006)]. The high statistics proton-proton J/psi data taken in 2005 are used to improve the baseline measurement and thus construct updated cold nuclear matter modification factors (R-dAu). A suppression of J/psi in cold nuclear matter is observed as one goes forward in rapidity (in the deuteron-going direction), corresponding to a region more sensitive to initial-state low-x gluons in the gold nucleus. The measured nuclear modification factors are compared to theoretical calculations of nuclear shadowing to which a J/psi (or precursor) breakup cross section is added. Breakup cross sections of sigma(breakup)=2.8(-1.4)(+1.7) (2.2(-1.5)(+1.6)) mb are obtained by fitting these calculations to the data using two different models of nuclear shadowing. These breakup cross-section values are consistent within large uncertainties with the 4.2 +/- 0.5 mb determined at lower collision energies. Projecting this range of cold nuclear matter effects to copper-copper and gold-gold collisions reveals that the current constraints are not sufficient to firmly quantify the additional hot nuclear matter effect.
8.	Abate, E., et al. (author) Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors 2008 In: Journal of Instrumentation. - 1748-0221. ; 3 Journal article (peer-reviewed)abstract The ATLAS (A Toroidal LHC ApparatuS) Inner Detector provides charged particle tracking in the centre of the ATLAS experiment at the Large Hadron Collider (LHC). The Inner Detector consists of three subdetectors: the Pixel Detector, the Semiconductor Tracker (SCT), and the Transition Radiation Tracker (TRT). This paper summarizes the tests that were carried out at the final stage of SCT+TRT integration prior to their installation in ATLAS. The combined operation and performance of the SCT and TRT barrel and endcap detectors was investigated through a series of noise tests, and by recording the tracks of cosmic rays. This was a crucial test of hardware and software of the combined tracker detector systems. The results of noise and cross-talk tests on the SCT and TRT in their final assembled configuration, using final readout and supply hardware and software, are reported. The reconstruction and analysis of the recorded cosmic tracks allowed testing of the offline analysis chain and verification of basic tracker performance parameters, such as efficiency and spatial resolution, in combined operation before installation.
9.	Abazov, V. M., et al. (author) Search for the pair production of scalar top quarks in the acoplanar charm jet final state in p(p)over-bar collisions at root s=1.96 TeV 2007 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 645:2-3, s. 119-127 Journal article (peer-reviewed)abstract A search for the pair production of scalar top quarks, (t) over tilde, has been performed in 360 pb(-1) of data from pp collisions at a center-of-mass energy of 1.96 TeV, collected by the D phi detector at the Fermilab Tevatron collider. The (t) over tilde decay mode considered is (t) over tilde -> c (chi) over tilde (0)(1), where (chi) over tilde (0)(1) is the lightest supersymmetric particle. The topology analyzed therefore consists of a pair of acoplanar heavy-flavor jets with missing transverse energy. The data and standard model expectation are in agreement, anda 95% C.L. exclusion domain in the (m((t) over tilde), m((chi) over tilde1)(0)) plane has been determined, extending the domain excluded by previous experiments.
10.	Abazov, V. M., et al. (author) The upgraded DO detector 2006 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 565:2, s. 463-537 Journal article (peer-reviewed)abstract The DO experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid -argon calorimeters and central muon detector, remaining from Run 1, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to DO.
11.	Abdesselam, A., et al. (author) Engineering for the ATLAS SemiConductor Tracker (SCT) end-cap 2008 In: Journal of Instrumentation. - 1748-0221. ; 3 Journal article (peer-reviewed)abstract The ATLAS SemiConductor Tracker (SCT) is a silicon-strip tracking detector which forms part of the ATLAS inner detector. The SCT is designed to track charged particles produced in proton-proton collisions at the Large Hadron Collider (LHC) at CERN at an energy of 14 TeV. The tracker is made up of a central barrel and two identical end-caps. The barrel contains 2112 silicon modules, while each end-cap contains 988 modules. The overall tracking performance depends not only on the intrinsic measurement precision of the modules but also on the characteristics of the whole assembly, in particular, the stability and the total material budget. This paper describes the engineering design and construction of the SCT end-caps, which are required to support mechanically the silicon modules, supply services to them and provide a suitable environment within the inner detector. Critical engineering choices are highlighted and innovative solutions are presented - these will be of interest to other builders of large-scale tracking detectors. The SCT end-caps will be fully connected at the start of 2008. Further commissioning will continue, to be ready for proton-proton collision data in 2008.
12.	Abazov, V. M., et al. (author) Experimental discrimination between charge 2e/3 top quark and charge 4e/3 exotic quark production scenarios 2007 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 98:4, s. 041801- Journal article (peer-reviewed)abstract We present the first experimental discrimination between the 2e/3 and 4e/3 top quark electric charge scenarios, using top quark pairs (t (t) over bar) produced in p (p) over bar collisions at root s =1.96 TeV by the Fermilab Tevatron Collider. We use 370 pb(-1) of data collected by the D0 experiment and select events with at least one high transverse momentum electron or muon, high transverse energy imbalance, and four or more jets. We discriminate between b- and (b) over bar -quark jets by using the charge and momenta of tracks within the jet cones. The data are consistent with the expected electric charge, \|q\|=2e/3. We exclude, at the 92% C.L., that the sample is solely due to the production of exotic quark pairs Q (Q) over bar with \|q\|=4e/3. We place an upper limit on the fraction of Q (Q) over bar pairs rho < 0.80 at the 90% C.L.
13.	Abazov, V. M., et al. (author) Limits on anomalous trilinear gauge couplings from WW -> e(+)e(-), WW -> e(+/-)mu(-/+), and WW ->mu(+)mu(-) events from pp collisions at root s=1.96 TeV 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:5, s. 057101- Journal article (peer-reviewed)abstract Limits are set on anomalous WW gamma and WWZ trilinear gauge couplings using W+W--> e(+)nu(e)e(-)(nu) over bar (e), W+W--> e(+/-)nu(e)mu(-/+)nu(mu), and W+W-->mu(+)nu(mu)mu(-)(nu) over bar (mu) events. The data set was collected by the Run II D0 detector at the Fermilab Tevatron Collider and corresponds to approximately 250 pb(-1) of integrated luminosity at root s=1.96 TeV. Under the assumption that the WW gamma couplings are equal to the WWZ couplings and using a form factor scale of Lambda=2.0 TeV, the combined 95% C.L. one-dimensional coupling limits from all three channels are -0.32
14.	Abazov, V. M., et al. (author) Measurement of B-d mixing using opposite-side flavor tagging 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:11, s. 112002- Journal article (peer-reviewed)abstract We report on a measurement of the B-d(0) mixing frequency and the calibration of an opposite-side flavor tagger in the D0 experiment. Various properties associated with the b quark on the opposite side of the reconstructed B meson are combined using a likelihood-ratio method into a single variable with enhanced tagging power. Its performance is tested with data, using a large sample of reconstructed semileptonic B ->mu(DX)-X-0 and B ->mu(DX)-X-* decays, corresponding to an integrated luminosity of approximately 1 fb(-1). The events are divided into groups depending on the value of the combined tagging variable, and an independent analysis is performed in each group. Combining the results of these analyses, the overall effective tagging power is found to be epsilon D-2=(2.48 +/- 0.21(-0.06)(+0.08))%. The measured B-d(0) mixing frequency Delta m(d)=0.506 +/- 0.020(stat)+/- 0.016(syst) ps(-1) is in good agreement with the world average value.
15.	Abazov, V. M., et al. (author) Measurement of beta (t -> Wb)/beta(t -> Wq) at root s=1.96 TeV 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 639:6, s. 616-622 Journal article (peer-reviewed)abstract We present the measurement of R = B(t -> Wb)/B(t -> Wq) in pp collisions at root s = 1.96 TeV, using 230 pb(-1) of data collected by the DO experiment at the Fermilab Tevatron Collider. We fit simultaneously R and the number (N-tt) of selected top quark pairs (tt), to the number of identified b-quark jets in events with one electron or one muon, three or more jets, and high transverse energy imbalance. To improve sensitivity, kinematical properties of events with no identified b-quark jets are included in the fit. We measure R = 1.03(-0.17)(0.19) (stat + syst), in good agreement with the standard model. We set lower limits of R > 0.61 and vertical bar V-tb vertical bar > 0.78 at 95% confidence level.
16.	Abazov, V. M., et al. (author) Measurement of the B-s(0) lifetime using semileptonic decays 2006 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:24, s. 241801- Journal article (peer-reviewed)abstract We report a measurement of the B-s(0) lifetime in the semileptonic decay channel B-s(0)-> D-s(-)mu(+)nu X (and its charge conjugate), using approximately 0.4 fb(-1) of data collected with the D0 detector during 2002-2004. Using 5176 reconstructed D-s(-)mu(+) signal events, we have measured the B-s(0) lifetime to be tau(B-s(0))=1.398 +/- 0.044(stat)(-0.025)(+0.028)(syst) ps. This is the most precise measurement of the B-s(0) lifetime to date.
17.	Abazov, V. M., et al. (author) Measurement of the CP-violation parameter of B-0 mixing and decay with p(p)over-bar ->mu mu X data 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:9, s. 092001- Journal article (peer-reviewed)abstract We measure the dimuon charge asymmetry A in p (p) over bar collisions at a center of mass energy root s=1960 GeV. The data was recorded with the D0 detector and corresponds to an integrated luminosity of approximately 1.0 fb(-1). Assuming that the asymmetry A is due to asymmetric B-0 <->(B) over bar (0) mixing and decay, we extract the CP-violation parameter of B-0 mixing and decay: ((epsilon B0))/(1+vertical bar epsilon B0 vertical bar 2)=(AB0)/(4)= -0.0023 +/- 0.0011(stat)+/- 0.0008(syst).A(B)(0) is the dimuon charge asymmetry from decays of B-0(B) over bar (0) pairs. The general case, with CP violation in both B-0 and B-s(0) systems, is also considered. Finally we obtain the forward-backward asymmetry that quantifies the tendency of mu(+) to go in the proton direction and mu(-) to go in the antiproton direction. The results are consistent with the standard model and constrain new physics.
18.	Abazov, V. M., et al. (author) Measurement of the isolated photon cross section in p(p)over-bar collisions at root s=1.96 TeV 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 639:3-4, s. 151-158 Journal article (peer-reviewed)abstract The cross section for the inclusive production of isolated photons has been measured in p (p) over bar collisions at root s = 1.96 TeV with the DO detector at the Fermilab Tevatron Collider. The photons span transverse momenta 23 to 300 GeV and have pseudorapidity vertical bar n vertical bar < 0.9. The cross section is compared with the results from two next-to-leading order perturbative QCD calculations. The theoretical predictions agree with the measurement within uncertainties.
19.	Abazov, V. M., et al. (author) Measurement of the ratios of the Z/gamma+ >= n jet production cross sections to the total inclusive Z/gamma cross section in p(p)over-bar collisions at root s=1.96 TeV 2008 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 658, s. 112- Journal article (peer-reviewed)abstract We present a study of events with Z bosons and associated jets produced at the Fermilab Tevatron collider in p p collisions at a center of mass energy of 1.96 TeV The data sample consists of nearly 14000 Z/gamma* -> e(+)e(-) candidates corresponding to an integrated luminosity of 0.4 fb(-1) collected with the D circle divide detector. Ratios of the Z/gamma+ >= n jet cross sections to the total inclusive Z/gamma cross section have been measured for n = 1-4 jets, and found to be in good agreement with a next-to-leading order QCD calculation and with a tree-level QCD prediction with parton shower simulation and hadronization.
20.	Abazov, V. M., et al. (author) Measurement of the t(t)over-bar production cross section in p(p)over-bar collisions at root s=1.96 TeV using secondary vertex b tagging 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:11, s. 112004- Journal article (peer-reviewed)abstract We report a new measurement of the t (t) over bar production cross section in p (beta) over bar 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(-1) of data collected using the D0 detector at the Fermilab Tevatron Collider, and enhancing the t (t) over bar content of the sample by tagging b jets with a secondary vertex tagging algorithm, the t (t) over bar production cross section is measured to be sigma(p (t) over bar -> t (t) over bar +X)=6.6 +/- 0.9(stat+syst) +/- 0.4(lum) pb. This cross section is the most precise D0 measurement to date for t (t) over bar production and is in good agreement with standard model expectations.
21.	Abazov, V. M., et al. (author) Measurement of the top quark mass in the dilepton channel 2007 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 655:1-2, s. 7-14 Journal article (peer-reviewed)abstract We present a measurement of the top quark mass in the dilepton channel based on approximately 370 pb(-1) of data collected by the DO experiment during Run R of the Fermilab Tevatron collider. We employ two different methods to extract the top quark mass. We show that both methods yield consistent results using ensemble tests of events generated with the DO Monte Carlo simulation. We combine the results from the two methods to obtain a top quark mass m(t) = 178.1 +/- 8.2 GeV. The statistical uncertainty is 6.7 GeV and the systematic uncertainty is 4.8 GeV.
22.	Abazov, V. M., et al. (author) Measurement of the top quark mass in the lepton plus jets final state with the matrix element method 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:9, s. 092005- Journal article (peer-reviewed)abstract We present a measurement of the top quark mass with the matrix element method in the lepton+jets final state. As the energy scale for calorimeter jets represents the dominant source of systematic uncertainty, the matrix element likelihood is extended by an additional parameter, which is defined as a global multiplicative factor applied to the standard energy scale. The top quark mass is obtained from a fit that yields the combined statistical and systematic jet energy scale uncertainty. Using a data set of 0.4 fb(-1) taken with the D0 experiment at Run II of the Fermilab Tevatron Collider, the mass of the top quark is measured using topological information to be: m(top)(center dot+jets)(topo)=169.2(-7.4)(+5.0)(stat+JES)(-1.4)(+1.5)(syst) GeV, and when information about identified b jets is included: m(top)(center dot+jets)(b-tag)=170.3(-4.5)(+4.1)(stat+ JES)(-1.8)(+1.2)(syst) GeV. The measurements yield a jet energy scale consistent with the reference scale.
23.	Abazov, V. M., et al. (author) Search for a heavy resonance decaying into a Z plus jet final state in p(p)over-bar collisions at root s=1.96 TeV using the D0 detector 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:1, s. 011104- Journal article (peer-reviewed)abstract We have searched for a heavy resonance decaying into a Z+jet final state in p (p) over bar collisions at a center of mass energy of 1.96 TeV at the Fermilab Tevatron collider using the D0 detector. No indication for such a resonance was found in a data sample corresponding to an integrated luminosity of 370 pb(-1). We set upper limits on the cross section times branching fraction for heavy resonance production at the 95% C.L. as a function of the resonance mass and width. The limits are interpreted within the framework of a specific model of excited quark production.
24.	Abazov, V. M., et al. (author) Search for associated Higgs boson production WH -> WWW-> l(+/-)nu l('+/-)nu(')+X in p(p)over-bar collisions at root S=1.96 TeV 2006 In:* Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:15, s. 151804- Journal article (peer-reviewed)abstract We present a search for associated Higgs boson production in the process p (p) over bar -> WH -> WWW-> l(+/-)nu l('+/-)nu(')+X in final states containing two like-sign isolated electrons or muons (e(+/-)e(+/-), e(+/-)mu(+/-), or mu(+/-)mu(+/-)). The search is based on D0 run II data samples corresponding to integrated luminosities of 360-380 pb(-1). No excess is observed over the predicted standard model background. We set 95% C.L. upper limits on sigma ->(p (p) over bar WH) x Br(H -> WW) between 3.2 and 2.8 pb for Higgs boson masses from 115 to 175 GeV.
25.	Abazov, V. M., et al. (author) Search for neutral Higgs bosons decaying to tau pairs in p(p)over-bar collisions at root s=1.96 TeV 2006 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:12, s. 121802- Journal article (peer-reviewed)abstract A search for the production of neutral Higgs bosons Phi decaying into tau(+)tau(-) final states in p (p) over bar collisions at a center-of-mass energy of 1.96 TeV is presented. The data, corresponding to an integrated luminosity of approximately 325 pb(-1), were collected by the D0 experiment at the Fermilab Tevatron Collider. Since no excess compared to the expectation from standard model processes is found, limits on the production cross section times branching ratio are set. The results are combined with those obtained from the D0 search for Phi b((b) over bar)-> b (b) over barb((b) over bar) and are interpreted in the minimal supersymmetric standard model.
26.	Abazov, V. M., et al. (author) Search for neutral, long-lived particles decaying into two muons in p(p)over-bar collisions at root s=1.96 TeV 2006 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:16, s. 161802- Journal article (peer-reviewed)abstract We present a search for a neutral particle, pair produced in pp collisions at root s=1.96 TeV, which decays into two muons and lives long enough to travel at least 5 cm before decaying. The analysis uses approximate to 380 pb(-1) of data recorded with the D0 detector. The background is estimated to be about one event. No candidates are observed, and limits are set on the pair-production cross section times branching fraction into dimuons + X for such particles. For a mass of 10 GeV and lifetime of 4x10(-11) s, we exclude values greater than 0.14 pb (95% C.L.). These results are used to limit the interpretation of NuTeV's excess of dimuon events.
27.	Abazov, V. M., et al. (author) Search for pair production of scalar bottom quarks in p(p)over-bar collisions at root s = 1.96 TeV 2006 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:17, s. 171806- Journal article (peer-reviewed)abstract A search for direct production of scalar bottom quarks ((b) over bar) is performed with 310 pb(-1) of data collected by the D0 experiment in p (p) over bar collisions at root s = 1.96 TeV at the Fermilab Tevatron Collider. The topology analyzed consists of two b jets and an imbalance in transverse momentum due to undetected neutralinos (chi(0)(1)), with chi(0)(1) assumed to be the lightest supersymmetric particle. We find the data consistent with standard model expectations, and set a 95% C.L. exclusion domain in the (m(b), m(chi 1)(0)) mass plane, improving significantly upon the results from run I of the Tevatron.
28.	Abazov, V. M., et al. (author) Search for particles decaying into a Z boson and a photon in p(p)over-bar collisions at root s=1.96 TeV 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 641:6, s. 415-422 Journal article (peer-reviewed)abstract We present the results of a search for a new particle X produced in p (p) over bar collisions at root s- = 1.96 TeV and subsequently decaying to Z gamma. The search uses 0.3 fb(-1) of data collected with the DO detector at the Fermilab Tevatron Collider. We set limits on the production cross section times the branching fraction sigma(p (p) over bar -> X) x B(X -> Z gamma) that range from 0.4 to 3.5 pb at the 95% C.L. for X with invariant masses between 100 and 1000 GeV/c(2), over a wide range of X decay widths.
29.	Abazov, V. M., et al. (author) Search for R-parity violating supersymmetry via the LL(E)over-bar couplings lambda(121), lambda(122) or lambda(133) in p(p)over-bar collisions at root s=1.96 TeV 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 638:5-6, s. 441-449 Journal article (peer-reviewed)abstract A search for gaugino pair production with a trilepton signature in the framework of R-parity violating supersymmetry via the couplings; lambda(121), lambda(122), or lambda(133) is presented. The data, corresponding to an integrated luminosity of L approximate to 360 pb(-1), were collected from April 2002 to August 2004 with the D0 detector at the Fermilab Tevatron Collider, at a center-of-mass energy of root s = 1.96 TeV. This analysis considers final states with three charged leptons with the flavor combinations eel, mu mu l, and ee tau (l = e or mu). No evidence for supersymmetry is found and limits at the 95% confidence level are set on the gaugino pair production cross section and lower bounds on the masses of the lightest neutralino and chargino are derived in two supersymmetric models.
30.	Abazov, V. M., et al. (author) Search for resonant second generation slepton production at the Fermilab Tevatron 2006 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:11, s. 111801- Journal article (peer-reviewed)abstract We present a search for supersymmetry in the R-parity violating resonant production and decay of smuons and muon sneutrinos in the channels mu ->chi(0)(1)mu, mu ->chi(0)(2,3,4)mu, and nu(mu)->chi(+/-)(1,2)mu. We analyzed 0.38 fb(-1) of integrated luminosity collected between April 2002 and August 2004 with the D0 detector at the Fermilab Tevatron Collider. The observed number of events is in agreement with the standard model expectation, and we calculate 95% C.L. limits on the slepton production cross section times branching fraction to gaugino plus muon, as a function of slepton and gaugino masses. In the framework of minimal supergravity, we set limits on the coupling parameter lambda(')(211), extending significantly previous results obtained in Run I of the Tevatron and at the CERN LEP collider.
31.	Abazov, V. M., et al. (author) Search for scalar leptoquarks in the acoplanar jet topology in p(p)over-bar collisions at root s=1.96 TeV 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 640:5-6, s. 230-237 Journal article (peer-reviewed)
32.	Abazov, V. M., et al. (author) Search for the rare decay B-s(0)->phi mu(+)mu(-) with the D0 detector 2006 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:3, s. 031107- Journal article (peer-reviewed)abstract We present a search for the flavor-changing neutral current decay B-s(0)->phi mu(+)mu(-) using about 0.45 fb(-1) of data collected in p (p) over bar collisions at root s=1.96 TeV with the D0 detector at the Fermilab Tevatron Collider. We find an upper limit on the branching ratio of this decay normalized to B-s(0)-> J/psi phi of B(B-s(0)->phi mu(+)mu(-))/B(B-s(0)-> J/psi phi)< 4.4x10(-3) at the 95% C.L. Using the central value of the world average branching fraction of B-s(0)-> J/psi phi, the limit corresponds to B(B-s(0)->phi mu(+)mu(-))< 4.1x10(-6) at the 95% C.L., the most stringent upper bound to date.
33.	Abazov, V. M., et al. (author) Search for the standard model Higgs boson in the p(p)over-bar -> ZH -> v(v)over-barb(b)over-bar channel 2006 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:16, s. 161803- Journal article (peer-reviewed)abstract We report a search for the standard model (SM) Higgs boson based on data collected by the D0 experiment at the Fermilab Tevatron Collider, corresponding to an integrated luminosity of 260 pb(-1). We study events with missing transverse energy and two acoplanar b jets, which provide sensitivity to the ZH production cross section in the nu nu bb channel, and to WH production when the lepton from the W ->center dot nu decay is undetected. The data are consistent with the SM background expectation, and we set 95% C.L. upper limits on sigma(pp -> ZH/WH) x B(H -> bb) from 3.4/8.3 to 2.5/6.3 pb, for Higgs-boson masses between 105 and 135 GeV.
34.	Abazov, V. M., et al. (author) Search for W ' boson production in the W ' -> t(b)over-bar decay channel 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 641:6, s. 423-431 Journal article (peer-reviewed)abstract We present a search for the production of a new heavy gauge boson W' that decays to a top quark and a bottom quark. We have analyzed 230 pb(-1) of data collected with the DO detector at the Fermilab Tevatron collider at a center-of-mass energy of 1.96 TeV. No significant excess of events above the standard model expectation is found in any region of the final state invariant mass distribution. We set upper limits on the production cross section of W' bosons times branching ratio to top quarks at the 95% confidence level for several different W, boson masses. We exclude masses between 200 and 610 GeV for a W' boson with standard-model-like couplings, between 200 and 630 GeV for a W, boson with right-handed couplings that is allowed to decay to both leptons and quarks, and between 200 and 670 GeV for a W' boson with right-handed couplings that is only allowed to decay to quarks.
35.	Abazov, V. M., et al. (author) Determination of the strong coupling constant from the inclusive jet cross section in pp collisions at s=1.96 TeV 2009 In: PHYS REV D. - 1550-7998 .- 1550-2368. ; 80, s. 111107- Journal article (peer-reviewed)abstract We determine the strong coupling constant alpha(s) and its energy dependence from the p(T) dependence of the inclusive jet cross section in pp collisions at s=1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50 < p(T)< 145 GeV. Using perturbative QCD calculations to order O(alpha(3)(s)) combined with O(alpha(4)(s)) contributions from threshold corrections, we obtain alpha(s)(M-Z)=0.1161(-0.0048)(+0.0041). This is the most precise result obtained at a hadron-hadron collider.
36.	Abazov, V. M., et al. (author) Search for supersymmetry in di-photon final states at root s=1.96 TeV 2008 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 659:5, s. 856-863 Journal article (peer-reviewed)abstract We report results of a search for supersymmetry (SUSY) with gauge-mediated symmetry breaking in di-photon events collected by the DO experiment at the Fermilab Tevatron Collider in 2002-2006. In 1.1 fb(-1) of data, we find no significant excess beyond the background expected from the standard model and set the most stringent lower limits to date for a standard benchmark model on the lightest neutralino and chargino masses of 125 GeV and 229 GeV, respectively, at 95% confidence.
37.	Abazov, V. M., et al. (author) Z gamma production and limits on anomalous ZZ gamma and Z gamma gamma couplings in pp collisions at root s=1.96 TeV 2007 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 653:5-6, s. 378-386 Journal article (peer-reviewed)abstract We present a study of eey and mu mu gamma events using 1109 (1009) pb-(1) of data in the electron (muon) channel, respectively. These data were collected with the DO detector at the Fermilab Tevatron pp collider at Is = 1.96 TeV. Having observed 453 (515) candidates in the eey (jtAy) final state, we measure the Z gamma production cross section for a photon with transverse energy ET > 7 GeV, separation between the photon and leptons Delta Rey > 0.7, and invariant mass of the di-lepton pair Mee > 30 GeV/(2)(c), to be 4.96 0.30(stat. + syst.) zE 0.30(lumi.) pb, in agreement with the Standard Model prediction of 4.74 0.22 pb. This is the most precise Zy cross section measurement at a hadron collider. We set limits on anomalous trilinear Zyy and ZZy gauge boson couplings of -0.085 < h(30)(y) < 0.084, -0.0053 < h(40)(y) < 0.0054 and -0.083 < h(30)(Z) < 0.082, 30 40 30 -0.0053 < h(40)(Z) < 0.0054 at the 95% C.L. for the form-factor scale A = 1.2 TeV. 40 .
38.	Adler, S. S., et al. (author) Azimuthal angle correlations for rapidity separated hadron pairs in d+Au collisions at root s(NN)=200 GeV 2006 In: Physical Review Letters. - 1079-7114. ; 96:22 Journal article (peer-reviewed)abstract Deuteron-gold (d+Au) collisions at the Relativistic Heavy Ion Collider provide ideal platforms for testing QCD theories in dense nuclear matter at high energy. In particular, models suggesting strong saturation effects for partons carrying small nucleon momentum fraction (x) predict modifications to jet production at forward rapidity (deuteron-going direction) in d+Au collisions. We report on two-particle azimuthal angle correlations between charged hadrons at forward/backward (deuteron/gold going direction) rapidity and charged hadrons at midrapidity in d+Au and p+p collisions at root s(NN)=200 GeV. Jet structures observed in the correlations are quantified in terms of the conditional yield and angular width of away-side partners. The kinematic region studied here samples partons in the gold nucleus with x similar to 0.1 to similar to 0.01. Within this range, we find no x dependence of the jet structure in d+Au collisions.
39.	Adler, S. S., et al. (author) Centrality dependence of charged hadron production in deuteron plus gold and nucleon plus gold collisions at root S-NN=200 GeV 2008 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 77:1 Journal article (peer-reviewed)abstract We present transverse momentum (p(T)) spectra of charged hadrons measured in deuteron-gold and nucleon-gold collisions at root s(NN)=200 GeV for four centrality classes. Nucleon-gold collisions were selected by tagging events in which a spectator nucleon was observed in one of two forward rapidity detectors. The spectra and yields were investigated as a function of the number of binary nucleon-nucleon collisions, nu, suffered by deuteron nucleons. A comparison of charged particle yields to those in p+p collisions show that yield per nucleon-nucleon collision saturates with nu for high momentum particles. We also present the charged hadron to neutral pion ratios as a function of p(T).
40.	Adler, S. S., et al. (author) Centrality dependence of pi(0) and eta production at large transverse momentum in root s(NN) = 200 GeV d+Au collisions 2007 In: Physical Review Letters. - 1079-7114. ; 98:17 Journal article (peer-reviewed)abstract The dependence of transverse momentum spectra of neutral pions and eta mesons with p(T) < 16 GeV/c and p(T) < 12 GeV/c, respectively, on the centrality of the collision has been measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) in d + Au collisions at root s(NN) = 200 GeV. The measured yields are compared to those in p + p collisions at the same root s(NN) scaled by the number of underlying nucleon-nucleon collisions in d + Au. At all centralities, the yield ratios show no suppression, in contrast to the strong suppression seen for central An + Au collisions at RHIC. Only a weak p(T) and centrality dependence can be observed.
41.	Adler, S. S., et al. (author) High transverse momentum eta meson production in p+p, d+Au, and Au+Au collisions at root s(NN)=200 GeV 2007 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 75:2 Research review (peer-reviewed)abstract Inclusive transverse momentum spectra of eta mesons in the range p(T)approximate to 2-12 GeV/c have been measured at midrapidity (vertical bar eta vertical bar < 0.35) by the PHENIX experiment at RHIC in p+p,d+Au, and Au+Au collisions at root s(NN)=200 GeV. The eta mesons are reconstructed through their eta ->gamma gamma channel for the three colliding systems as well as through the eta ->pi(0)pi(+)pi(-) decay mode in p+p and d+Au collisions. The nuclear modification factor in d+Au collisions, R-dAu(p(T))approximate to 1.0-1.1, suggests at most only modest p(T) broadening ("Cronin enhancement"). In central Au+Au reactions, the eta yields are significantly suppressed, with R-AuAu(p(T))approximate to 0.2. The ratio of eta to pi(0) yields is approximately constant as a function of p(T) for the three colliding systems in agreement with the high-p(T) world average of R-eta/pi(0)approximate to 0.5 in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions for a wide range of center-of-mass energies (root sNN approximate to 3-1800 GeV) as well as, for high scaled momentum x(p), in e(+)e(-) annihilations at root s=91.2 GeV. These results are consistent with a scenario where high-p(T) eta production in nuclear collisions at the Relativistic Heavy Ion Collider is largely unaffected by initial-state effects but where light-quark mesons (pi(0),eta) are equally suppressed due to final-state interactions of the parent partons in the dense medium produced in Au+Au reactions.
42.	Adler, S. S., et al. (author) Jet properties from dihadron correlations in p plus p collisions at root s=200 GeV 2006 In: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 74:7 Journal article (peer-reviewed)abstract The properties of jets produced in p+p collisions at root s=200 GeV are measured using the method of two-particle correlations. The trigger particle is a leading particle from a large transverse momentum jet while the associated particle comes from either the same jet or the away-side jet. Analysis of the angular width of the near-side peak in the correlation function determines the jet-fragmentation transverse momentum j(T). The extracted value, root < j(T)(2)>=585 +/- 6(stat)+/- 15(sys) MeV/c, is constant with respect to the trigger particle transverse momentum, and comparable to the previous lower root s measurements. The width of the away-side peak is shown to be a convolution of j(T) with the fragmentation variable, z, and the partonic transverse momentum, k(T). The < z > is determined through a combined analysis of the measured pi(0) inclusive and associated spectra using jet-fragmentation functions measured in e(+)e(-) collisions. The final extracted values of k(T) are then determined to also be independent of the trigger particle transverse momentum, over the range measured, with value of root < k(T)(2)>=2.68 +/- 0.07(stat)+/- 0.34(sys) GeV/c.
43.	Adler, S. S., et al. (author) Jet structure from dihadron correlations in d+Au collisions at root S-NN=200 GeV 2006 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 73:5 Journal article (peer-reviewed)abstract Dihadron correlations at high transverse momentum p(T) in d+Au collisions at root s(NN)=200 GeV at midrapidity are measured by the PHENIX experiment at the Relativistic Heavy Ion Collider. From these correlations, we extract several structural characteristics of jets: the root-mean-squared transverse momentum of fragmenting hadrons with respect to the jet root < j(T)(2)>, the mean sine-squared of the azimuthal angle between the jet axes < sin(2)phi(jj)>, and the number of particles produced within the dijet that are associated with a high-p(T) particle (dN/dx(E) distributions). We observe that the fragmentation characteristics of jets in d+Au collisions are very similar to those in p+p collisions and that there is little dependence on the centrality of the d+Au collision. This is consistent with the nuclear medium having little influence on the fragmentation process. Furthermore, there is no statistically significant increase in the value of < sin(2)phi(jj)> from p+p to d+Au collisions. This constrains the effect of multiple scattering that partons undergo in the cold nuclear medium before and after a hard collision.
44.	Adler, S. S., et al. (author) Measurement of direct photon production in p+p collisions at root s=200 GeV 2007 In: Physical Review Letters. - 1079-7114. ; 98:1 Journal article (peer-reviewed)abstract Cross sections for midrapidity production of direct photons in p+p collisions at the Relativistic Heavy Ion Collider (RHIC) are reported for transverse momenta of 3 < p(T)< 16 GeV/c. Next-to-leading order perturbative QCD (pQCD) describes the data well for p(T)> 5 GeV/c, where the uncertainties of the measurement and theory are comparable. We also report on the effect of requiring the photons to be isolated from parton jet energy. The observed fraction of isolated photons is well described by pQCD for p(T)> 7 GeV/c.
45.	Adler, S. S., et al. (author) Nuclear effects on hadron production in d plus Au collisions at root S-NN=200 GeV revealed by comparison with p plus p data 2006 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 74:2 Journal article (peer-reviewed)abstract PHENIX has measured the centrality dependence of midrapidity pion, kaon, and proton transverse momentum distributions in d+Au and p+p collisions at root s(NN) = 200 GeV. The p+p data provide a reference for nuclear effects in d+Au and previously measured Au+Au collisions. Hadron production is enhanced in d+Au, relative to independent nucleon-nucleon scattering, as was observed in lower energy collisions. The nuclear modification factor for (anti)protons is larger than that for pions. The difference increases with centrality but is not sufficient to account for the abundance of baryon production observed in central Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC). The centrality dependence in d+Au shows that the nuclear modification factor increases gradually with the number of collisions encountered by each participant nucleon. We also present comparisons with lower energy data as well as with parton recombination and other theoretical models of nuclear effects on particle production.
46.	Adler, S. S., et al. (author) Production of omega mesons at large transverse momenta in p+p and d+Au collisions at root S(NN) = 200 GeV 2007 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 75:5 Journal article (peer-reviewed)abstract The PHENIX experiment at RHIC has measured the invariant cross section for omega-meson production at midrapidity in the transverse momentum range 2.5 < p(T)< 9.25 GeV/c in p+p and d+Au collisions at root s(NN) = 200 GeV. Measurements in two decay channels (omega ->pi(0)pi(+)pi(-) and omega ->pi(0)gamma) yield consistent results, and the reconstructed omega mass agrees with the accepted value within the p(T) range of the measurements. The omega/pi(0) ratio is found to be 0.85 +/- 0.05(stat)+/- 0.09(sys) in p+p and 0.94 +/- 0.08(stat)+/- 0.12(sys) in d+Au collisions, independent of p(T). The nuclear modification factor R-dA(omega) is 1.03 +/- 0.12(stat)+/- 0.21(sys) and 0.83 +/- 0.21(stat)+/- 0.17(sys) in minimum bias and central (0-20%) d+Au collisions, respectively.
47.	Abazov, M, et al. (author) Direct Measurement of the Mass Difference between Top and Antitop Quarks 2009 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 103:13, s. 132001- Journal article (peer-reviewed)abstract We present a measurement of the mass difference between t and (t) over bar quarks in lepton + jets final states of t (t) over bar events in 1 fb(-1) of data collected with the D0 detector from Fermilab Tevatron Collider p (p) over bar collisions at root s = 1.96 TeV. The measured mass difference of 3.8 +/- 3.7 GeV is consistent with the equality of t and (t) over bar masses. This is the first direct measurement of a mass difference between a quark and its antiquark partner.
48.	Abazov, V. M., et al. (author) Combined D0 measurements constraining the CP-violating phase and width difference in the B-s(0) system 2007 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998. ; 76:5, s. 057101- Journal article (peer-reviewed)abstract We combine the D0 measurement of the width difference between the light and heavy B-s(0) mass eigenstates and of the CP-violating mixing phase determined from the time-dependent angular distributions in the B-s(0)-> J/psi phi decays along with the charge asymmetry in semileptonic decays also measured with the D0 detector. With the additional constraint from the world average of the flavor-specific B-s(0) lifetime, we obtain Delta Gamma(s)equivalent to(Gamma(L)-Gamma(H))=0.13 +/- 0.09 ps(-1) and vertical bar phi(s)vertical bar=0.70(-0.47)(+0.39) or Delta Gamma(s)=-0.13 +/- 0.09 ps(-1) and vertical bar phi(s)vertical bar=2.44(-0.39)(+0.47). The data sample corresponds to an integrated luminosity of 1.1 fb(-1) accumulated with the D0 detector at the Fermilab Tevatron Collider.
49.	Abazov, V. M., et al. (author) Evidence for production of single top quarks and first direct measurement of vertical bar V-tb vertical bar 2007 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 98:18, s. 181802- Journal article (peer-reviewed)abstract The D0 Collaboration presents first evidence for the production of single top quarks at the Fermilab Tevatron < p(p)over bar > collider. Using a 0.9 fb(-1) dataset, we apply a multivariate analysis to separate signal from background and measure sigma(< p(p)over bar >-> tb+X,tqb+X)=4.9 +/- 1.4 pb. The probability to measure a cross section at this value or higher in the absence of a signal is 0.035%, corresponding to a 3.4 standard deviation significance. We use the cross section measurement to directly determine the Cabibbo-Kobayashi-Maskawa matrix element that describes the Wtb coupling and find 0.68 <= 1 at 95% C.L. within the standard model.
50.	Abazov, V. M., et al. (author) Lifetime difference and CP-violating phase in the B-s(0) system 2007 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 98:12, s. 121801- Journal article (peer-reviewed)abstract From an analysis of the decay B-s(0)-> J/psi phi, we obtain the width difference between the light and heavy mass eigenstates Delta Gamma equivalent to(Gamma(L)-Gamma(H))=0.17 +/- 0.09(stat)+/- 0.02(syst) ps(-1) and the CP-violating phase phi(s)=-0.79 +/- 0.56(stat)(-0.01)(+0.14)(syst). Under the hypothesis of no CP violation (phi(s)equivalent to 0), we obtain 1/Gamma=tau/(B-s(0))=1.52 +/- 0.08(stat)(-0.03)(+0.01)(syst) ps and Delta Gamma=0.12(-0.10)(+0.08)(stat)+/- 0.02(syst) ps(-1). The data sample corresponds to an integrated luminosity of about 1.1 fb(-1) accumulated with the D0 detector at the Fermilab Tevatron collider. This is the first direct measurement of the CP-violating mixing phase in the B-s(0) system.

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