We present a measurement of the correlation between the spins of t and (t) over bar quarks produced in proton-antiproton collisions at the Tevatron Collider at a center-of-mass energy of 1.96 TeV. We ...apply a matrix element technique to dilepton and single-lepton+jets final states in data accumulated with the DO detector that correspond to an integrated luminosity of 9.7 fb(-1). The measured value of the correlation coefficient in the off-diagonal basis, O-off = 0.89 +/- 0.22 (stat + syst), is in agreement with the standard model prediction, and represents evidence for a top-antitop quark spin correlation difference from zero at a level of 4.2 standard deviations.
The D0 Silicon Microstrip Tracker Ahmed, S.N.; Aoki, M.; Åsman, B. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2011, Letnik:
634, Številka:
1
Journal Article
Recenzirano
This paper describes the mechanical design, the readout chain, the production, testing and the installation of the Silicon Microstrip Tracker of the D0 experiment at the Fermilab Tevatron collider. ...In addition, we describe the performance and operational experience of the detector during the experiment data collection between 2001 and 2010.
Electron and photon identification in the Do experiment Augsten, K.; Avila, C.; Bandurin, D. V. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2014, Letnik:
750
Journal Article
Recenzirano
Odprti dostop
The electron and photon reconstruction and identification algorithms used by the DO Collaboration at the Fermilab Tevatron collider are described. The determination of the electron energy scale and ...resolution is presented. Studies of the performance of the electron and photon reconstruction and identification are summarized. The results are based on measurements of Z boson decay events of Z ee and Z gamma ll(i=e mu) collected in pp(over bar) collisions at a center- of- mass energy of 1.96 TeV using an integrated luminosity of up to10 fb(-1.)
We present a measurement of top quark polarization in t ¯ t pair production in p ¯ p collisions at √ s = 1.96 TeV using data corresponding to 9.7 fb -1 of integrated luminosity recorded with the D0 ...detector at the Fermilab Tevatron Collider. We consider final states containing a lepton and at least three jets. The polarization is measured through the distribution of lepton angles along three axes: the beam axis, the helicity axis, and the transverse axis normal to the t ¯ t production plane. This is the first measurement of top quark polarization at the Tevatron using lepton + jet final states and the first measurement of the transverse polarization in t ¯ t production. The observed distributions are consistent with standard model predictions of nearly no polarization.
We present the first measurement of the CP violating charge asymmetry in B-+/- -> mu(+/-)nu D-mu(0) decays using the full Run II integrated luminosity of 10.4 fb(-1) in proton-antiproton ...collisions collected with the D0 detector at the Fermilab Tevatron Collider. We measure a difference in the yield of B- and B+ mesons in these decays by fitting the reconstructed invariant mass distributions. This results in an asymmetry of A(mu D0) = -0.14 +/- 0.20 %, which is consistent with standard model predictions.
The inclusive cross section of top quark-antiquark pairs produced in p$\bar{p}$ collisions at √ s = 1.96 TeV is measured in the lepton + jets and dilepton decay channels. The data sample corresponds ...to 9.7 fb -1 of integrated luminosity recorded with the D0 detector during Run II of the Fermilab Tevatron Collider. Employing multivariate analysis techniques we measure the cross section in the two decay channels and we perform a combined cross section measurement. For a top quark mass of 172.5 GeV, we measure a combined inclusive top quark-antiquark pair production cross section of σ t $\bar{t}$ = 7.26 ± 0.13 ( stat ) $+0.57\atop{-0.50}$ ( syst ) pb which is consistent with standard model predictions. We also perform a likelihood fit to the measured and predicted top quark mass dependence of the inclusive cross section, which yields a measurement of the pole mass of the top quark. The extracted value is m t = 172.8 ± 1.1 ( theo ) $+3.3\atop{-3.1}$ ( exp ) GeV .
We measure the forward-backward asymmetries A(FB) of charged Xi and Omega baryons produced in p (p) over bar collisions recorded by the D0 detector at the Fermilab Tevatron collider at root s = 1.96 ...TeV as a function of the baryon rapidity y. We find that the asymmetries A(FB) for charged Xi and Omega baryons are consistent with zero within statistical uncertainties.
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