SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Jarvis D.) ;pers:(Kehoe R.)"

Sökning: WFRF:(Jarvis D.) > Kehoe R.

  • Resultat 1-10 av 111
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Abazov, V. M., et al. (författare)
  • Measurement of the top quark mass in the dilepton channel
  • 2007
  • Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 655:1-2, s. 7-14
  • Tidskriftsartikel (refereegranskat)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.
  •  
2.
  • Abazov, V. M., et al. (författare)
  • Direct observation of the strange b baryon Xi(-)(b)
  • 2007
  • Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 99:5, s. 052001-
  • Tidskriftsartikel (refereegranskat)abstract
    • We report the first direct observation of the strange b baryon Xi(-)(b)(Xi) over bar (+)(b)). We reconstruct the decay Xi(-)(b)-->J/psi Xi(-), with J/psi-->mu(+)mu(-), and Xi(-)-->Lambda pi(-)-->p pi(-)pi(-) in p (p) over bar collisions at root s = 1.96 TeV. Using 1.3 fb(-1) of data collected by the D0 detector, we observe 15.2 +/- 4.4(stat)(-0.4)(+1.9)(syst) Xi(-)(b) candidates at a mass of 5.774 +/- 0.011(stat) +/- 0.015(syst) GeV. The significance of the observed signal is 5.5 sigma, equivalent to a probability of 3.3 x 10(-8) of it arising from a background fluctuation. Normalizing to the decay Lambda(b)-->J/psi Lambda, we measure the relative rate sigma(Xi(-)(b))xB(Xi(-)(b)-->J/psi Xi)/ sigma(Lambda(b))xB(Lambda(b)-->J/psi Lambda) = 0.28 +/- 0.09(stat)(-0.08)(+0.09)(syst).
  •  
3.
  • Abazov, V. M., et al. (författare)
  • Measurement of B-d mixing using opposite-side flavor tagging
  • 2006
  • Ingår i: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:11, s. 112002-
  • Tidskriftsartikel (refereegranskat)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.
  •  
4.
  • Abazov, V. M., et al. (författare)
  • Measurement of the CP-violation parameter of B-0 mixing and decay with p(p)over-bar ->mu mu X data
  • 2006
  • Ingår i: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 74:9, s. 092001-
  • Tidskriftsartikel (refereegranskat)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.
  •  
5.
  • Abazov, V. M., et al. (författare)
  • Measurement of the Lambda(0)(b) lifetime using semileptonic decays
  • 2007
  • Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 99:18, s. 182001-
  • Tidskriftsartikel (refereegranskat)abstract
    • We report a measurement of the Lambda(0)(b) lifetime using a sample corresponding to 1.3 fb(-1) of data collected by the D0 experiment in 2002-2006 during run II of the Fermilab Tevatron collider. The Lambda(0)(b) baryon is reconstructed via the decay Lambda(0)(b)->mu(nu) over bar Lambda X-+(c). Using 4437 +/- 329 signal candidates, we measure the Lambda(0)(b) lifetime to be tau(Lambda(0)(b))=1.290(-0.110)(+0.119)(stat)(-0.091)(+0.087)(syst) ps, which is among the most precise measurements in semileptonic Lambda(0)(b) decays. This result is in good agreement with the world average value.
  •  
6.
  • Abazov, V. M., et al. (författare)
  • Measurement of the Lambda(b) lifetime in the exclusive decay Lambda(b)-> J/psi Lambda
  • 2007
  • Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 99:14, s. 142001-
  • Tidskriftsartikel (refereegranskat)abstract
    • We have measured the Lambda(b) lifetime using the exclusive decay Lambda(b)-> J/psi Lambda, based on 1.2 fb(-1) of data collected with the D0 detector during 2002-2006. From 171 reconstructed Lambda(b) decays, where the J/psi and Lambda are identified via the decays J/psi ->mu(+)mu(-) and Lambda -> p pi, we measured the Lambda(b) lifetime to be tau(Lambda(b))=1.218(-0.115)(+0.130)(stat)+/- 0.042(syst) ps. We also measured the B-0 lifetime in the decay B-0 -> J/psi(mu(+)mu(-))K-S(0)(pi(+)pi(-)) to be tau(B-0)=1.501(-0.074)(+0.078)(stat)+/- 0.050(syst) ps, yielding a lifetime ratio of tau(Lambda(b))/tau(B-0)=0.811(-0.087)(+0.096)(stat)+/- 0.034(syst).
  •  
7.
  • Abazov, V. M., et al. (författare)
  • Measurement of the muon charge asymmetry from W boson decays
  • 2008
  • Ingår i: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998. ; D:77, s. 011106-
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a measurement of the muon charge asymmetry from W boson decays using 0.3 fb(-1) of data collected at root s =1.96 GeV between 2002 and 2004 with the D0 detector at the Fermilab Tevatron (p) over bar Collider. We compare our findings with expectations from next-to-leading-order calculations performed using the CTEQ6.1M and MRST04 NLO parton distribution functions. Our findings can be used to constrain future parton distribution function fits.
  •  
8.
  • Abazov, V. M., et al. (författare)
  • Measurement of the p(p)over-bar -> WZ+X cross section at root s=1.96 TeV and limits on WWZ trilinear gauge couplings
  • 2007
  • Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 76:11
  • Tidskriftsartikel (refereegranskat)abstract
    • We present measurements of the process p (P) over bar -> WZ + X -> l 'nu(l ')l (l) over bar at root s = 1:96 TeV,where l and l ' are electrons or muons. Using 1 fb(-1) of data from the D0 experiment, we observe 13 candidates with an expected background of 4.5 +/- 0.6 events and measure a cross section sigma(WZ) = 2.7(-1.3)(+1.7) pb. From the number of observed events and the Z boson transverse momentum distribution, we limit the trilinear WWZ gauge couplings to -0: 17 <= lambda(Z) <= 0.21 (Delta k(Z) <= 0.29(lambda(Z) = 0) at the 95% C.L. for a form factor scale Lambda = 2 TeV. Further, assuming that Delta g(1)(Z) = Delta k(Z), we find -0.12 <= Delta k(Z) <= 0.29(lambda(Z) = 0) at the 95% C. L. These are the most restrictive limits on the WWZ couplings available to date.
  •  
9.
  • Abazov, V. M., et al. (författare)
  • Measurement of the t(t)over-bar production cross section in p(p)over-bar collisions at root s=1.96 TeV using kinematic characteristics of lepton plus jets events
  • 2007
  • Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 76:9
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a measurement of the top quark pair production cross section in p (p) over bar collisions at root s=1.96 TeV utilizing 425 pb(-1) of data collected with the D0 detector at the Fermilab Tevatron Collider. We consider the final state of the top quark pair containing one high-p(T) electron or muon and at least four jets. We exploit specific kinematic features of t (t) over bar events to extract the cross section. For a top quark mass of 175 GeV, we measure sigma(t (t) over bar)=6.4(-1.2)(+1.3)(stat)+/- 0.7(syst)+/- 0.4(lum) pb, in good agreement with the standard model prediction.
  •  
10.
  • Abazov, V. M., et al. (författare)
  • Measurement of the t(t)over-bar production cross section in p(p)over-bar collisions using dilepton events
  • 2007
  • Ingår i: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998. ; 76:5, s. 052006-
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a measurement of the t (t) over bar pair production cross section in p (p) over bar collisions at root s=1.96 TeV utilizing approximately 425 pb(-1) of data collected with the D0 detector. We consider decay channels containing two high p(T) charged leptons (either e or mu) from leptonic decays of both top-daughter W bosons. These were gathered using four sets of selection criteria, three of which required that a pair of fully identified leptons (i.e., e mu, ee, or mu mu) be found. The fourth approach imposed less restrictive criteria on one of the lepton candidates and required that at least one hadronic jet in each event be tagged as containing a b quark. For a top quark mass of 175 GeV, the measured cross section is 7.4 +/- 1.4(stat)+/- 1.0(syst) pb and for the current Tevatron average top quark mass of 170.9 GeV, the resulting value of the cross section is 7.8 +/- 1.8(stat+syst) pb.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 111
Typ av publikation
tidskriftsartikel (110)
forskningsöversikt (1)
Typ av innehåll
refereegranskat (111)
Författare/redaktör
Abbott, B. (111)
Andeen, T. (111)
Begel, M. (111)
Borissov, G. (111)
Brandt, A. (111)
Brock, R. (111)
visa fler...
Brooijmans, G. (111)
Burdin, S. (111)
Calvet, S. (111)
Chakraborty, D. (111)
Cheu, E. (111)
Cooke, M. (111)
De, K. (111)
Duflot, L. (111)
Fiedler, F. (111)
Fox, H. (111)
Gillberg, D. (111)
Haas, A. (111)
Han, L. (111)
Hensel, C. (111)
Jakobs, K. (111)
Kupco, A. (111)
Kvita, J. (111)
Lammers, S. (111)
Meyer, J. (111)
Mitrevski, J. (111)
Piegaia, R. (111)
Pleier, M. -A. (111)
Qian, J. (111)
Rijssenbeek, M. (111)
Sawyer, L. (111)
Schwanenberger, C. (111)
Schwienhorst, R. (111)
Severini, H. (111)
Shabalina, E. (111)
Snyder, S. (111)
Sopczak, A. (111)
Sosebee, M. (111)
Spurlock, B. (111)
Stark, J. (111)
Strandberg, J. (111)
Strauss, M. (111)
Taylor, W. (111)
Tsybychev, D. (111)
Vachon, B. (111)
Watts, G. (111)
White, A. (111)
Wicke, D. (111)
Yacoob, S. (111)
visa färre...
Lärosäte
Uppsala universitet (111)
Kungliga Tekniska Högskolan (86)
Stockholms universitet (23)
Språk
Engelska (111)
Forskningsämne (UKÄ/SCB)
Naturvetenskap (111)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy