We report a combination of the CDF and D0 measurements of the inclusive single top quark production cross section in the s- and t-channels in ppbar collisions at a center of mass energy of 1.96TeV. The total integrated luminosity included in CDF's analysis is 3.2 fb^-1 and D0's analysis has 2.3 fb^-1. A Bayesian analysis is used to extract the cross section from the distributions of multivariate discriminants provided by the collaborations. For a top quark mass m_t=170 GeV/c^2, we measure a cross section of 2.76 +0.58 -0.47 pb. We extract the CKM matrix element |Vtb|=0.88+-0.07 with a 95% C.L. lower limit of |Vtb|>0.77.
The measurement of heavy quark cross-sections provides important tests of the QCD theory. This paper reviews recent measurements of single b-quark and correlated b-quark cross-sections at CDF. Two new measurements of the single b-quark production at CDF agree with the first result from CDF Run II. This clarifies the experimental situation and confirms the recent agreement of theoretical prediction with data. A new measurement of the correlated $b\bar{b}$ cross-section with dimuon events at CDF is presented. It agrees with theory and it does not confirm the anomalously large $b\bar{b}$ cross-se…
Results on inclusive jet production in proton-antiproton collisions at sqrt(s) =1.96 TeV based on 1 fb-1 of CDF Run II data are presented. Measurements are preformed using the k_T algorithm in a wide range of jet transverse momentum and jet rapidity. The measured cross sections are compared to next-to-leading order perturbative QCD calculations.
Preliminary results of ttbar cross section measurements and single top exclusion limits of the Tevatron experiments CDF and D0 are presented. The different measurements are based on a dataset between 140 and 200 inverse pb corresponding to a data taking period from spring 2002 to September 2003. The ttbar cross section measurements are consistent with each other and the Standard Model prediction. Data and Monte-Carlo prediction are in good agreement in the search for single top quark. Its observation is anticipated with roughly 2 inverse fb integrated luminosity.
Using data collected during the 1992-93 collider run at Fermilab, CDF has made measurements of correlated $b$ quark cross section where one $b$ is detected via a muon from semileptonic decay and the second $b$ is detected with secondary vertex techniques. We report on measurements of the cross section as a function of the momentum of the second $b$ and as a function of the azimuthal separation of the two $b$ quarks, for transverse momentum of the initial $b$ quark greater than 15 GeV. Results are compared to QCD predictions.
We present a measurement of the isolated direct photon cross section in p-pbar collisions at sqrt(s) = 1.8 TeV and |eta| < 0.9 using data collected between 1994 and 1995 by the Collider Detector at Fermilab (CDF). The measurement is based on events where the photon converts into an electron-positron pair in the material of the inner detector, resulting in a two-track event signature. To remove pi0 -> gamma gamma and eta -> gamma gamma events we use a new background subtraction technique which takes advantage of the tracking information available in a photon conversion event. We find that the s…
Recent measurements of jet and multijet production cross sections from ppbar collisions recorded with the Collider Detector at Fermilab (CDF) are summarized. First Run II results of the inclusive one jet cross section at sqrt(s) = 1.96 TeV as well as prospects for future extensions of this measurement are presented. We also studied the properties of three-jet events in Run Ib data at sqrt(s) = 1.8 TeV. All results are compared to predictions of Quantum Chromodynamics at next-to-leading order perturbation theory.
Using data collected during the 1992-1993 collider run at Fermilab, CDF has made measurements of correlated $b$ quark cross sections where one $b$ is detected from the lepton from semileptonic decay and the second $b$ is detected with secondary vertex techniques. We report on measurements of the cross section as a function of the momentum of the second $b$ and as a function of the azimuthal separation of the two $b$ quarks, for transverse momentum of the initial $b$ quark greater than 15 GeV. The vertex reconstruction techniques are valid over a large range in transverse momentum, starting at …
Measurements of the ttbar production cross-section at \sqrt{s} = 1.96TeV in proton-antiproton collisions were performed by the CDF and Dzero collaborations using ttbar final states where both W's decay hadronically. Each experiment uses luminosity of about 160pb^-1 of data collected during Run II of the Fermilab Tevatron collider. Beside kinematical observables both experiments take advantage of identifying b-jets based on lifetime tagging. While CDF counts the number of b-tags over background after a cut based analysis, Dzero counts the excess of events after a neural network based kinematica…
We present the first exclusive observation of the ttbar to hadronic tau + jets decay channel. Using these events from 1.96 TeV ppbar collisions at CDF, we measure the ttbar cross section as well as the top quark mass. Events require a single hadronic tau, large missing transverse energy, and exactly 4 jets of which at least one must be tagged as a b jet. The cross section measurement is extracted from a Poisson likelihood function based on the observed number of events and the predicted number of signal and background events for a given ttbar cross section. The mass is extracted from a likelih…
We present recent top physics results in the CDF including updates of top mass, \ttbar cross section, single top search, forward-backward asymmetry, and the differential cross section of \ttbar. Most of measurements utilize close to the integrated luminosity of 3 fb$^{-1}$.
Recent jet results in $p\bar{p}$ collisions at $\sqrt{s}$=1.96 TeV from the CDF experiment at the Tevatron are presented. The jet inclusive cross section is compared to next-to-leading order QCD prediction in different rapidity regions. The $b$-jet inclusive cross section is measured exploiting the long lifetime and large mass of $B$-hadrons. Jet shapes, W+jets and W/Z+photon cross sections are also measured and compared to expectations from QCD production.
We report two complementary measurements of the WW+WZ cross section in the final state consisting of an electron or muon, missing transverse energy, and jets, performed using p\bar{p} collision data at sqrt{s} = 1.96 TeV collected by the CDF II detector. The first method uses the dijet invariant mass distribution while the second more sensitive method uses matrix-element calculations. The result from the second method has a signal significance of 5.4 sigma and is the first observation of WW+WZ production using this signature. Combining the results gives sigma_{WW+WZ} = 16.0 +/- 3.3 pb, in agre…
We report on measurements of the Upsilon(1S), Upsilon(2S) and Upsilon(3S) differential and integrated cross sections in pp(bar) collisions at sqrt(s)=1.8 TeV. The three resonances were reconstructed through the decay Upsilon-->mu(+)mu(-). The cross section measurements are compared to theoretical models of direct bottomonium production.
This Letter reports a measurement of the cross section for producing pairs of central prompt isolated photons in proton-antiproton collisions at a total energy of 1.96 TeV using data corresponding to 9.5/fb integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. The measured differential cross section is compared to three calculations derived from the theory of strong interactions. These include a prediction based on a leading order matrix element calculation merged with parton shower, a next-to-leading order, and a next-to-next-to-leading order calculation. The firs…
We present measurements of the top-antitop production cross section in b-tagged lepton + jets events from proton-antiproton collisions at 1.96 TeV using the CDF detector at Fermilab. B-jets are tagged with either a secondary vertex algorithm, or a soft lepton tagger that identifies muons from B hadron semileptonic decays. With Tevatron Run II data, we estimate the top-antitop signal fraction in two different ways: by estimating the various background contributions, and by fitting directly the leading jet transverse energy spectrum for the signal and background contributions. A subset of the sa…
We present a measurement of the top-quark pair production cross-section in proton-antiproton collisions at $\sqrt{s}$=1.96 TeV. The data were collected at the Fermilab Tevatron by the CDF II detector and correspond to an integrated luminosity of 8.8 fb$^{-1}$, representing the complete CDF Run II data set. We select events consistent with the production of top-quark pairs by requiring the presence of two reconstructed leptons, an imbalance in the total event transverse momentum, and jets. At least one jet is required to be identified as consistent with the fragmentation of a bottom quark using…
A measurement of the cross section for the inclusive production of isolated photons by the CDF experiment at the Fermilab Tevatron collider is presented. The measurement covers the pseudorapidity region |eta^gamma|<1.0 and the transverse energy range E_T^gamma>30 GeV and is based on 2.5/fb of integrated luminosity. The sample is almost a factor of seven larger than those used for recent published results and extends the E_T^gamma coverage by 100 GeV. The result agrees with next-to-leading order perturbative QCD calculations within uncertainties over the range 50<E_Tgamma<400 GeV, though the en…
We report on measurements of the inclusive jet production cross section as a function of the jet transverse momentum in pp-bar collisions at sqrt{s} = 1.96 TeV}, using the k_T algorithm and a data sample corresponding to 1.0 fb^-1 collected with the Collider Detector at Fermilab in Run II. The measurements are carried out in five different jet rapidity regions with |yjet| < 2.1 and transverse momentum in the range 54 < \ptjet < 700 GeV/c. Next-to-leading order perturbative QCD predictions are in good agreement with the measured cross sections.
We present preliminary results on inclusive direct photon production in $p\bar{p}$ collisions at $\sqrt{s}$=1.96 TeV, using data collected with the upgraded Collider Detector at Fermilab in Run II, corresponding to an integrated luminosity of 451 pb$^{-1}$. Measurements are performed as a function of the photon transverse momentum for photons with $p_{T}>$30 GeV and $|η|<$1.0. Photons are required to be isolated in the calorimeter. The measurement is corrected to the hadron level and compared to NLO pQCD predictions.
A measurement of W->e nu + n-jet cross sections in ppbar collisions at sqrt(s)=1.96 TeV using the Collider Detector at Fermilab in Run II is presented. The measurement is based on an integrated luminosity of 320 pb-1, and includes events with jet multiplicity from >= 1 to >= 4. In each jet multiplicity sample the differential and cumulative cross sections with respect to the transverse energy of the n^(th)-leading jet are measured. For W+>=2 jets the differential cross section with respect to the 2-leading jets invariant mass m_(j_(1)j_(2)) and angular separation Delta R_(j_(1)j_(2)) is also r…
The cross section for the inclusive production of W bosons in association with jets in ppbar collisions at sqrt(s)=1.96 TeV using the Collider Detector at Fermilab (CDF II) is presented. The measurement is based on an integrated luminosity of 320pb^-1, and includes events with up to 4 or more jets. In each jet multiplicity sample the differential and cumulative cross sections with respect to the transverse energy of the i^th-jet are measured. For W+>=2 jets the differential cross section with respect to the 2-leading jets invariant mass m_j1j2 and angular separation Delta R_j1j2 is also report…
We report a measurement of the single top quark production cross section in 2.2 ~fb-1 of p-pbar collision data collected by the Collider Detector at Fermilab at sqrt{s}=1.96 TeV. Candidate events are classified as signal-like by three parallel analyses which use likelihood, matrix element, and neural network discriminants. These results are combined in order to improve the sensitivity. We observe a signal consistent with the standard model prediction, but inconsistent with the background-only model by 3.7 standard deviations with a median expected sensitivity of 4.9 standard deviations. We mea…
We combine results from CDF and D0's direct searches for the standard model (SM) Higgs boson (H) produced in ppbar collisions at the Fermilab Tevatron at sqrt{s}=1.96 TeV, focusing on the decay H\rightarrowγγ. We compute upper limits on the Higgs boson production cross section times the decay branching fraction in the range 100<m_H<150 GeV/c^2, and we interpret the results in the context of the standard model. We use the MSTW08 parton distribution functions and the latest theoretical cross section predictions when testing for the presence of a SM Higgs boson. With datasets corresponding to 7.0…
We present a combined measurement of the production cross section of VZ (V=W or Z) events in final states containing charged leptons (electrons or muons) or neutrinos, and heavy flavor jets, using data collected by the CDF and D0 detectors at the Fermilab Tevatron Collider. The analyzed samples of ppbar collisions at sqrt(s)=1.96 TeV correspond to integrated luminosities of 7.5 - 9.5 fb-1. Assuming the ratio of the production cross sections sigma(WZ) and sigma(ZZ) as predicted by the standard model, we measure the sum of the WZ and ZZ cross sections to be 4.47 +- 0.64 (stat) +0.73 -0.72 (syst)…
We present a measurement of the top quark mass and of the top-antitop pair production cross section using p-pbar data collected with the CDFII detector at the Tevatron Collider at the Fermi National Accelerator Laboratory and corresponding to an integrated luminosity of 2.9 fb-1. We select events with six or more jets satisfying a number of kinematical requirements imposed by means of a neural network algorithm. At least one of these jets must originate from a b quark, as identified by the reconstruction of a secondary vertex inside the jet. The mass measurement is based on a likelihood fit in…
The most recent results on top quark physics at CDF are reported. Measurements of cross-section and mass are presented, and the status of single top quark production searches are discussed. The results obtained from probing various top quark properties are also presented.
The top quark plays an important role in the grand scheme of particle physics, and is also interesting on its own merits. We present recent results from CDF on top-quark physics based on 100-200/pb of p-pbar collision data. We have measured the t-tbar cross section in different decay modes using several different techniques, and are beginning our studies of top-quark properties. New analyses for this conference include a measurement of the t-tbar cross section in the lepton-plus-jets channel using a neural net to distinguish signal and background events, and measurements of top-quark branching…
Recently, the CDF experiment at the Fermilab Tevatron has used complementary methods to make multiple measurements of the singly produced top quark cross section. All analyses use the same dataset with more than 2 fb^-1 of CDF data and event selection based on W+2 or W+3 jet events with at least one b-tagged jet. However, due to differences in analysis techniques these results are not fully correlated and a combination provides improved experimental precision. Two independent methods are used to combine the results. This combination results in an improved measurement of the single top producti…
Fermilab's Tevatron accelerator is recently performing at record luminosities that enables a program systematically addressing the physics of top quarks. The CDF collaboration has analyzed up to 5/fb of proton anti-proton collisions from the Tevatron at a center of mass energy of 1.96 TeV. The large datasets available allow to push top quark measurements to higher and higher precision and have lead to the recent observation of electroweak single top quark production at the Tevatron. This article reviews recent results on top quark physics from the CDF experiment.
The top quark, discovered in 1995 by the CDF and D0 collaborations at the Tevatron proton antiproton collider at Fermilab, has undergone intense studies in the last 20 years. Currently, CDF and D0 converge on their measurements of top-antitop quark production cross sections using the full Tevatron data sample. In these proceedings, the latest results on inclusive and differential measurements of top-antitop quark production cross sections at the Tevatron are reported.
We present the recent results of top-quark physics using up to 6 fb$^{-1}$ of $p\bar{p}$ collisions analyzed by the CDF collaboration. The large number of top quark events analyzed, of the order of several thousands, allows stringent checks of the standard model predictions. Also, the top quark is widely believed to be a window to new physics. We present the latest measurements of top quark intrinsic properties as well as direct searches for new physics in the top sector.
A summary of the most up-to-date top quark mass measurements at CDF is presented. These analyses use top-antitop candidate events detected in the CDF experiment at the Tevatron collider with an integrated luminosity of up to ~3/fb. The combination of all those measurements together with the corresponding top mass measurements from the concurrently running D0 experiment at the Tevatron yields a world average of M_t=[173.1+/-0.6(stat.)+/-1.1(syst.)] GeV/c^2.
Direct (prompt) photon production is a field of very high interest in hadron colliders. It provides probes to search for new phenomena and to test QCD predictions. In this article, two recent cross-section results for direct photon production using the full CDF Run II data set are presented: diphoton production and photon production in association with a heavy quark.
We present a search for a Higgs boson decaying to two W bosons in ppbar collisions at sqrt(s)=1.96 TeV center-of-mass energy. The data sample corresponds to an integrated luminosity of 3.0 fb-1 collected with the CDF II detector. We find no evidence for production of a Higgs boson with mass between 110 and 200 GeV/c^2, and determine upper limits on the production cross section. For the mass of 160 GeV/c^2, where the analysis is most sensitive, the observed (expected) limit is 0.7 pb (0.9 pb) at 95% Bayesian credibility level which is 1.7 (2.2) times the standard model cross section.
In their 1997 paper, CDF measured sigma_effective, the normalization factor that relates the cross section for double parton scattering to the product of the inclusive cross sections of the two individual scatters, in a model in which they are assumed to be independent. In his 2007 paper, Treleani pointed out that CDF used a non-standard definition, in which the double parton scattering cross section corresponds to exactly two scatters, rather than the more conventional one in which it is the inclusive two-scatter cross section. He also estimated the correction from one definition to the other…
It has been more than 15 years since the discovery of the top quark. Great strides have been made in the measurement of the top quark mass and the properties of it. Most results show consistency with the standard model. However, using 5 fb$^{-1}$ data, recent measurements of the asymmetry in the production of top and anti-top quark pair have demonstrated surprisingly large values at CDF. Using 4 fb$^{-1}$ data, D0 also has similar effect.
This document was written as part of the PANIC 2008 conference proceedings in Eilat Israel. We review top mass measurements performed at CDF Run II through October of 2008. The basic algorithms used in many mass measurements are discussed as are some common systematic difficulties. Mass results in combination with the D0 Collaboration are presented, and the implications on the Standard Model Higgs mass are discussed.
I summarize recent top quark physics results from the Fermilab Tevatron experiments. Since the observation of the top quark by CDF and D0 in 1995, the experimental focus has shifted to a detailed study of the top quark's properties. This article describes recent measurements of the top quark production cross section, mass, kinematic properties, branching ratios, $V_{tb}$, and the W polarization in top decays.
This letter presents results on the precision measurement of the top quark mass and a combination of the best CDF top mass measurements. A combination by the TevEWWG (Tevatron electroweak working group) of the best top mass results from CDF and D0 in Run 1 and Run 2 of the Tevatron is also presented. This result is the current world average, and offers an uncertainty less than 1%. The new mass value has been included in traditional LEP EWWG fits to precision electroweak data, and implications for the Standard Model Higgs have been derived.
Using data collected with the CDF Run II detector, new measurements on bottom production cross-sections are presented. The latest achievements in bottom hadron spectroscopy are discussed. The results are based on a large sample of semileptonic and hadronic decays of bottom states made available by triggers based on the precise CDF tracking system.
The top quark with its mass of about 172 GeV/c^2 is the most massive fundamental particle observed by experiment. In this talk we highlight the most recent measurements of several top quark properties performed with the CDF detector based on data samples corresponding to integrated luminosities up to 1 fb-1. These results include a search for top quark pair production via new massive resonances, measurements of the helicity of the W boson from top-quark decay, and a direct limit on the lifetime of the top quark.
We present the most recent CDF results in the measurements of the decay and production vertex of the top-quark. New results on forward-backward asymmetry in top-antitop events are presented. Also, recent measurements of the branching fractions of top-quark are discussed. Finally, measurements in single top events, where top-quark is produced through electroweak processes, are presented. Despite the much larger number of top events collected at the LHC, due to the symmetric initial state and the better signal-to-background ratio in specific channels, some results will be lasting heritage of the…
The mass of the top quark M_top is interesting both as a fundamental parameter of the standard model and as an important input to precision electroweak tests. The Collider Detector at Fermilab (CDF) has a robust program of top quark mass analyses, including the most precise single measurement, M_top = 173.4 +/- 2.8 GeV/c^2, using 680 pb^-1 of ppbar collision data. A combination of current results from CDF gives M_top = 172.0 +/- 2.7 GeV/c^2, surpassing the stated goal of 3 GeV/c^2 precision using 2 fb^-1 of data. Finally, a combination with current D0 results gives a world average top quark ma…
We present the recent results of top-quark physics using up to 6 fb$^{-1}$ of $p \bar p$ collisions at a center of mass energy of $\sqrt s$ = 1.96 TeV analyzed by the CDF collaboration. Thanks to this large data sample, precision top quark measurements are now a reality at the Tevatron. Further, several new physics signals could appear in this large dataset. We will present the latest measurements of top quark intrinsic properties as well as direct searches for new physics in the top sector.
We present results of the search for the super-symmetric partner of the top quark, the stop quark, decaying to a b-quark and chargino with the subsequent chargino decay into a neutralino, lepton and neutrino. Using the data sample corresponding to 2.7 inv fb of integrated luminosity, collected with the CDF Detector of the Tevatron collider, we reconstruct the stop mass of candidate events and set 95% C. L. upper limits on masses of the stop quark, chargino and neutralino and the branching ratio of chargino to neutralino+lepton+neutrino.
We combine results of CDF and D0 searches for a Standard-Model Higgs boson in data from ppbar collisions at the Fermilab Tevatron with sqrt(s) = 1.96 TeV. With 260-950 pb-1 collected at D0, and 360-1000 pb-1 collected at CDF, the 95%CL upper limits are a factor of 10.4(3.8) higher than the expected cross section for mH =115(160) GeV/c2. This result extends significantly the individual limits of each experiment.
It has recently been pointed out that CDF data for the cross section of high-p_t charged particles show an excess of up to three orders of magnitude over QCD predictions, a feature tentatively ascribed to possible violations of factorisation. We observe that for p_t > 80 GeV the measured charged-particle cross sections become of the same order as jet cross sections. Combining this information with data on charged particle distributions within jets allows us to rule out the hypothesis that the CDF data could be interpreted in terms of QCD factorisation violation. We also comment on the difficul…
We summarize the top-quark mass measurements from the CDF and D0 experiments at Fermilab. We combine published Run-I measurements with the most recent Run-II measurements. Taking correlated uncertainties into account the resulting preliminary world average top-quark mass is Mt=170.9+/-1.1(sta)+/-1.5(sys) GeV/c2 assuming Gaussian systematic uncertainties. Adding in quadrature yields a total uncertainty of 1.8 GeV/c2, corresponding to a relative precision of 1.1% on the mass of the top quark.
We present the results of a search for associated production of the lightest chargino and next-to-lightest neutralino using 1 fb$^{-1}$ of $\sqrt s$ = 1.96 TeV p$\rm \bar p$ data collected with the CDF detector at the Tevatron. We combine the results of several multi-lepton final states to set upper limits on the cross section times branching ratio for chargino-neutralino production as a function of the chargino mass.
We report on the first measurement of the rapidity distribution dsigma/dy over nearly the entire kinematic region of rapidity for e^+e^- pairs in the Z-boson region of 66<M_{ee}<116 GeV/c^2 and at higher mass M_{ee}>116 GeV/c^2. The data sample consists of 108 pb^{-1} of ppbar collisions at \sqrt{s}=1.8 TeV taken by the Collider Detector at Fermilab during 1992--1995. The total cross section in the $Z$-boson region is measured to be 252 +- 11 pb. The measured total cross section and dσ/dy are compared with quantum chromodynamics calculations in leading and higher orders.
We summarize the top-quark mass measurements from the CDF and D0 experiments at Fermilab. We combine published Run-I (1992-1996) measurements with the most recent preliminary Run-II (2001-present) measurements using up to 2.8 fb^-1 of data. Taking correlated uncertainties properly into account the resulting preliminary world average mass of the top quark is M_t = 172.4 +/- 0.7 (stat.) +/- 1.0 (syst.) GeV/c^2, assuming Gaussian systematic uncertainties. Adding in quadrature yields a total uncertainty of 1.2 GeV/c^2, corresponding to a relative precision of 0.7% on the top-quark mass.
We summarize the top-quark mass measurements from the CDF and D0 experiments at Fermilab. We combine published RunI (1992-1996) measurements with the most recent RunII (2001-present) measurements using up to 2/fb of data. Taking correlated uncertainties properly into account the resulting preliminary world average mass of the top quark is Mt=172.6 +/- 0.8(sta) +/- 1.1(sys) GeV/c2, assuming Gaussian systematic uncertainties. Adding in quadrature yields a total uncertainty of 1.4 GeV/c2, corresponding to a relative precision of 0.8% on the top-quark mass.
We present a new measurement of the $B^+$ meson differential cross section $dσ/d p_T$ at $\sqrt{s}=1960$ GeV. The data correspond to an integrated luminosity of 739pb$^{-1}$ collected with the upgraded CDF detector (CDF II) at the Fermilab Tevatron collider. $B^+$ candidates are reconstructed through the decay $B^+ \to J/ψK^+$, with $J/ψ\to μ^+ μ^-$. The integrated cross section for producing $B^+$ mesons with $p_T \geq 6$ GeV/c and $|y| \leq 1$ is measured to be $2.78 \pm 0.24 μ$b
We summarize the current top-quark mass measurements from the CDF and D0 experiments at Fermilab. We combine published Run I (1992--1996) results with the most precise published and preliminary Run II (2001--2011) measurements based on data corresponding to up to 9.7 fb$^{-1}$ of $p\bar{p}$ collisions. Taking correlations of uncertainties into account, and combining the statistical and systematic uncertainties, the resulting preliminary Tevatron average mass of the top quark is $M_{top} = 174.34 \pm 0.64 ~GeV/c^2$, corresponding to a relative precision of 0.37%.
We report on a search for the production of the Higgs boson decaying to two bottom quarks accompanied by two additional quarks. The data sample used corresponds to an integrated luminosity of approximately 4\,\invfb\, of \ppbar\, collisions at $\sqrt{s}=1.96$\,TeV recorded by the CDF II experiment. This search includes twice the integrated luminosity of the previous published result, uses analysis techniques to distinguish jets originating from light flavor quarks and those from gluon radiation, and adds sensitivity to a Higgs boson produced by vector boson fusion. We find no evidence of the H…
We summarize the current top-quark mass measurements from the CDF and DO experiments at Fermilab. We combine published Run I (1992--1996) measurements with the most precise published and preliminary Run II (2001--2011) measurements based on data sets corresponding to up to 8.7 fb^{-1} of ppbar collisions. Taking correlations of uncertainties into account, and combining the statistical and systematic uncertainties, the resulting preliminary Tevatron average mass of the top quark is M_top = 173.20 \pm 0.87 GeV/c^2, corresponding to a relative precision of 0.50 %.
We present recent results from CDF in the search for new phenomena appearing in the top quark samples. These results use data from proton-antiproton collisions at sqrt{s} = 1.96 TeV corresponding to an integrated luminosity ranging from 195 pb^-1 to 760 pb^-1. No deviations are observed from the Standard Model expectations, so upper limits on the size of possible new phenomena are set.
We summarize the top-quark mass measurements from the CDF and DO experiments at Fermilab. We combine published Run-I (1992-1996) measurements with the most recent preliminary Run-II (2001-present) measurements using up to 1 fb-1 of data. Taking correlated uncertainties properly into account the resulting preliminary world average mass of the top quark is Mtop = 171.4 +/- 1.2 (stat) +/- 1.8 (syst) GeV/c2, which corresponds to a total uncertainty of 2.1 GeV/c2. The top-quark mass is now known with a precision of 1.2%.
We present recent results on top quark pair production cross section and forward-backward asymmetry at the Tevatron. Three new cross section measurements from CDF and one new measurement from DO are presented that utilize the full dataset available. A new DO top cross section combination gives a ttbar production cross section of sigma_ttbar = 7.83 + 0.46-0.45 (stat) + 0.64-0.53 (syst) +-0.48 (lumi). The new CDF cross section combination for ttbar production is found to be 7.0 +- 0.3 (stat) +- 0.4 (syst) +- 0.4 (lumi) pb giving a total uncertainty of 9%, very close to the that of the current be…