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Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of W-Boson Polarization in Top-Quark Decay in p(p)over-bar Collisions at root s=1.96 TeV Type Journal Article
Year 2010 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 105 Issue 4 Pages 042002 - 8pp
Keywords
Abstract We report measurements of the polarization of W bosons from top-quark decays using 2.7 fb(-1) of p (p) over bar collisions collected by the CDF II detector. Assuming a top-quark mass of 175 GeV/c(2), three measurements are performed. A simultaneous measurement of the fraction of longitudinal (f(0)) and right-handed (f(0)) W bosons yields the model- independent results f(0) =0. 88 +/- 0.11(stat) +/- 0.06(syst) and f(+) = 0.15 +/- 0.07(stat) +/- 0.06(syst) with a correlation coefficient of -0.59. A measurement of f(0) [f(+)] constraining f(+) [f(0)] to its standard model value of 0.0 [0.7] yields f(0) 0.70 + 0.07(stat) +/- 0.04(syst) [f(+) – 0.01 +/- 0.02(stat) +/- 0.05(syst)]. All these results are consistent with standard model expectations. We achieve the single most precise measurements of f(0) for both the model- independent and modeldependent determinations.
Address [Aaltonen, T.; Mehtala, P.; Orava, R.; Osterberg, K.; Saarikko, H.; Torre, S.; van Remortel, N.] Univ Helsinki, Div High Energy Phys, Dept Phys, FIN-00014 Helsinki, Finland
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes ISI:000280234400009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 279
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Author ATLAS Collaboration (Aad, G. et al); Amoros, G.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Fuster, J.; Garcia, C.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Perez Garcia-Estañ, M.T.; Ros, E.; Salt, J.; Solans, C.A.; Sanchez, J.; Torro Pastor, E.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A.
Title Search for New Particles in Two-Jet Final States in 7 TeV Proton-Proton Collisions with the ATLAS Detector at the LHC Type Journal Article
Year 2010 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 105 Issue 16 Pages 161801 - 19pp
Keywords
Abstract A search for new heavy particles manifested as resonances in two-jet final states is presented. The data were produced in 7 TeV proton-proton collisions by the LHC and correspond to an integrated luminosity of 315 nb(-1) collected by the ATLAS detector. No resonances were observed. Upper limits were set on the product of cross section and signal acceptance for excited-quark (q*) production as a function of q* mass. These exclude at the 95% C. L. the q* mass interval 0: 30< m(q)*< 1:26 TeV, extending the reach of previous experiments.
Address [Aad, G.; Ahles, F.; Aktas, A.; Beckingham, M.; Bernhard, R.; Bianchi, R. M.; Bitenc, U.; Bruneliere, R.; Caron, S.; Carpentieri, C.; Christov, A.; Dahlhoff, A.; Dietrich, J.; Eckert, S.; Fehling-Kaschek, M.; Flechl, M.; Glatzer, J.; Hartert, J.; Heldmann, M.; Herten, G.; Horner, S.; Jakobs, K.; Joos, D.; Ketterer, C.; Koenig, S.; Kollefrath, M.; Kononov, A. I.; Kuehn, S.; Lai, S.; Landgraf, U.; Lohwasser, K.; Ludwig, I.; Ludwig, J.; Lumb, D.; Maassen, M.; Mahboubi, K.; Meinhardt, J.; Meirose, B.; Messmer, I.; Mohr, W.; Nilsen, H.; Parzefall, U.; Pfeifer, B.; Bueso, X. Portell; Rammensee, M.; Runge, K.; Rurikova, Z.; Schmidt, E.; Schroff, D.; Schumacher, M.; Stoerig, K.; Sundermann, J. E.; Temming, K. K.; Thoma, S.; Tobias, J.; Venturi, M.; Vivarelli, I.; von Radziewski, H.; Warsinsky, M.; Webel, M.; Weiser, C.; Werner, M.; Wiik, L. A. M.; Winkelmann, S.; Xie, S.; Zimmermann, S.] Univ Freiburg, Fak Math & Phys, D-79104 Freiburg, Germany
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes ISI:000282753000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 358
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Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of the Ratio sigma(t(t)over-bar)/sigma(Z/gamma*-> ll) and Precise Extraction of the t(t)over-bar Cross Section Type Journal Article
Year 2010 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 105 Issue 1 Pages 012001 - 7pp
Keywords
Abstract We report a measurement of the ratio of the t (t) over bar to Z/gamma* production cross sections in root s = 1.96 TeV p (p) over bar collisions using data corresponding to an integrated luminosity of up to 4.6 fb(-1), collected by the CDF II detector. The t (t) over bar cross section ratio is measured using two complementary methods, a b-jet tagging measurement and a topological approach. By multiplying the ratios by the well-known theoretical Z/gamma* -> ll cross section predicted by the standard model, the extracted t (t) over bar cross sections are effectively insensitive to the uncertainty on luminosity. A best linear unbiased estimate is used to combine both measurements with the result sigma(t (t) over bar) = 7.70 +/- 0.52 pb, for a top-quark mass of 172.5 GeV/c(2).
Address [Blair, R. E.; Byrum, K. L.; LeCompte, T.; Nodulman, L.; Paramanov, A. A.; Wagner, R. G.; Wicklund, A. B.] Argonne Natl Lab, Argonne, IL 60439 USA
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes ISI:000279273300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 282
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Author BABAR Collaboration (del Amo Sanchez, P. et al); Lopez-March, N.; Martinez-Vidal, F.; Milanes, D.A.; Oyanguren, A.
Title Search for f(J)(2220) in Radiative J/psi Decays Type Journal Article
Year 2010 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 105 Issue 17 Pages 172001 - 7pp
Keywords
Abstract We present a search for f(J)(2220) production in radiative J/psi --> gamma f(J)(2220) decays using 460 fb(-1) of data collected with the BABAR detector at the SLAC PEP-II e(+)e(-) collider. The f(J)(2220) is searched for in the decays to K+K- and (KSKS0)-K-0. No evidence of this resonance is observed, and 90% confidence level upper limits on the product of the branching fractions for J/psi --> gamma f(J)(2220) and f(J)(2220) --> K+K-((KSKS0)-K-0) as a function of spin and helicity are set at the level of 10(-5), below the central values reported by the Mark III experiment.
Address [Sanchez, P. del Amo; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, Lab Annecy Le Vieux Phys Particules LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes ISI:000283126900005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 351
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Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Direct Top-Quark Width Measurement at CDF Type Journal Article
Year 2010 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 105 Issue 23 Pages 232003 - 7pp
Keywords
Abstract We present a measurement of the top-quark width in the lepton + jets decay channel of t (t) over bar events produced in p (p) over bar collisions at Fermilab's Tevatron collider and collected by the CDF II detector. From a data sample corresponding to 4.3 fb(-1) of integrated luminosity, we identify 756 candidate events. The top-quark mass and the mass of the hadronically decaying W boson that comes from the top-quark decay are reconstructed for each event and compared with templates of different top-quark widths (Gamma(t)) and deviations from nominal jet energy scale (Delta(JES)) to perform a simultaneous fit for both parameters, where Delta(JES) is used for the in situ calibration of the jet energy scale. By applying a Feldman-Cousins approach, we establish an upper limit at 95% confidence level (CL) of Gamma(t) < 7.6 GeV and a two-sided 68% CL interval of 0.3 GeV < Gamma(t) < 4.4 GeV for a top-quark mass of 172.5 GeV/c(2), which are consistent with the standard model prediction.
Address [Aaltonen, T.; Brucken, E.; Devoto, F.; Mehtala, P.; Orava, R.] Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes ISI:000286736800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 518
Permanent link to this record