We report the observation of single top-quark production using 3.2 fb(-1) of ppover collision data with sqrts=1.96 TeV collected by the Collider Detector at Fermilab. The significance of the ...observed data is 5.0 standard deviations, and the expected sensitivity for standard model production and decay is in excess of 5.9 standard deviations. Assuming m(t) = 175 GeV/c(2), we measure a cross section of 2.3(-0.5);(+0.6)(stat + syst) pb, extract the CKM matrix-element value |V(tb)| = 0.91 + or - 0.11(stat + syst) + or - 0.07(theory), and set the limit |V(tb)| > 0.71 at the 95% C.L.
Higgs boson studies at the Tevatron Agnew, J. P.; Annovi, A.; Bandurin, D. V. ...
Physical review. D, Particles, fields, gravitation, and cosmology,
09/2013, Letnik:
88, Številka:
5
Journal Article
Recenzirano
Odprti dostop
We combine searches by the CDF and DO Collaborations for the standard model Higgs boson with mass in the range 90- 200 GeV /c super(2) produced in the gluon-gluon fusion, WH, ZH, ttH, and vector ...boson fusion processes, and decaying in the H arrow right bb, H arrow right W super(+)W super(-), H arrow right ZZ, H arrow right tau super(+)tau super(-), and H arrow right gamma gamma modes. The data correspond to integrated luminosities of up to 10 fb super(-1) and were collected at the Fermilab Tevatron in pp collisions at radicals = 1.96 TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140 GeV /c super(2). The local significance corresponds to 3.0 standard deviations at mH = 125 GeV /c super(2), consistent with the mass of the Higgs boson observed at the LHC, and we expect a local significance of 1.9 standard deviations. We separately combine searches for H arrow right bb, H arrow right W super(+)W super(-), H arrow right tau super(+)t super(-), and H arrow right gamma gamma . The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 125 GeV /c super(2).
The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the ...asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of sqrts=1.96 TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A_{FB}^{ttover ¯}=0.128±0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.
Evidence is reported for a narrow structure near the $J/\psi\phi$ threshold in exclusive $B^+\to J/\psi\phi K^+$ decays produced in $\bar{p} p $ collisions at $\sqrt{s}=1.96 \TeV$. A signal of ...$14\pm5$ events, with statistical significance in excess of 3.8 standard deviations, is observed in a data sample corresponding to an integrated luminosity of $2.7 \ifb$, collected by the CDF II detector. The mass and natural width of the structure are measured to be $4143.0\pm2.9(\mathrm{stat})\pm1.2(\mathrm{syst}) \MeVcc$ and $11.7^{+8.3}_{-5.0}(\mathrm{stat})\pm3.7(\mathrm{syst}) \MeVcc$.
We present a search for high-mass neutral resonances using dimuon data corresponding to an integrated luminosity of 2.3 fb(-1) collected in ppover collisions at sqrts=1.96 TeV by the CDF II detector ...at the Fermilab Tevatron. No significant excess above the standard model expectation is observed in the dimuon invariant-mass spectrum. We set 95% confidence level upper limits on sigmaBR(pp-->X-->micromicro), where X is a boson with spin-0, 1, or 2. Using these cross section limits, we determine lower mass limits on sneutrinos in R-parity-violating supersymmetric models, Z' bosons, and Kaluza-Klein gravitons in the Randall-Sundrum model.
We present a measurement of the total decay width of the top quark using events with top-antitop quark pair candidates reconstructed in the final state with one charged lepton and four or more ...hadronic jets. We use the full Tevatron run II data set of sqrts=1.96 TeV proton-antiproton collisions recorded by the CDF II detector. The top quark mass and the mass of the hadronically decaying W boson are reconstructed for each event and compared with distributions derived from simulated signal and background samples to extract the top quark width (Γtop) and the energy scale of the calorimeter jets with in situ calibration. For a top quark mass Mtop=172.5 GeV/c2, we find 1.10<Γtop<4.05 GeV at 68% confidence level, which is in agreement with the standard model expectation of 1.3 GeV and is the most precise direct measurement of the top quark width to date.
PDF
