Combination of Single Top Quark Production Results from CDF
R. C. Group, C. I. Ciobanu, K. Lannon, C. Plager
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ICHEP08, 3 pages, 2 figures, Published Proceedings 34th International Conference on High Energy Physics, Philadelphia, Pennsylvania, July 30-August 5, 2008
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 production cross section and also the CKM matrix element V_tb.
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.
We summarize and combine direct measurements of the width of the W boson in data collected by the Tevatron experiments CDF and D0 at Fermilab. Results from CDF and D0 RunI (1992-1995) have been combined with the CDF 200 pb^-1 results from the first period of RunII (2001-2004) and the recent 1 fb^-1 result in the electron channel from D0 (2002-2006). The results are corrected for any inconsistencies in parton distribution functions and assumptions about electroweak parameters used in the different analyses. The resulting Tevatron average for the width of the W boson is Gamma_W = 2,046 +- 49.
The results on the direct measurements of the W-boson width, based on the data collected by the Tevatron experiments CDF and DØat Fermilab during {\RunI} from 1992 to 1996 and {\RunII} since 2001 are summarized. The combination of the published {\RunI} and preliminary {\RunII} results, taking correlated uncertainties properly into account, is presented. The resulting preliminary Tevatron average for the total decay width of the W boson is: $\GW=2078\pm87 \MeV$, where the total error consists of a statistical part of $62 \MeV$ and a systematic part of $60 \MeV$.
We summarize and combine the results on the direct measurements of the mass of the W boson in data collected by the Tevatron experiments CDF and D0 at Fermilab. Results from CDF Run-0 (1988-1889) and Run-I (1992-1995) have been combined with D0 results from Run-I, the CDF 200 pb^(-1) published results from the first period of Run-II (2001-2004) and the recent 1 fb^(-1) result in the electron channel from D0 (2002-2006). The results are corrected for any inconsistencies in parton distribution functions and assumptions about electroweak parameters used in the different analyses. The resulting Te…
We summarize and combine the results on the direct measurements of the mass of the W boson in data collected by the Tevatron experiments CDF and D0 at Fermilab. Earlier results from CDF Run-0 (1988--1989), D0 and CDF Run-I (1992--1995) and D0 results from 1/fb (2002--2006) of Run-II data are now combined with two new, high statistics Run-II measurements: a CDF measurement in both electron and muon channels using 2.2/fb of integrated luminosity collected between 2002 and 2007, and a D0 measurement in the electron channel using 4.3/fb collected between 2006 and 2009. As in previous combinations,…
We combine the results of the CDF and D0 searches for chargino and neutralino production in Gauge-Mediated SUSY using the two-photon and missing Et channel. The data are p-pbar collisions produced at the Tevatron with sqrt(s)=1.96 TeV, with 202 pb^-1 collected at CDF and 263 pb^-1 collected at D0. The combined limit excludes a chargino mass less than 209 GeV/c^2. This result significantly extends the individual experimental limits.
The results on the measurements of the top-quark mass, based on the data collected by the Tevatron experiments CDF and DØat Fermilab during Run I from 1992 to 1996, and Run II since 2001 are summarized. The combination of the published Run I and preliminary Run II results, taking correlated uncertainties properly into account, is presented. The resulting preliminary world average for the mass of the top quark is: $\MT=174.3 \pm 3.4 \GeVc2$, where the total error consists of a statistical part of $2.0 \GeVc2$ and a systematic part of $2.8 \GeVc2$.
The results on the direct measurements of the W-boson mass and width, based on the data collected by the Tevatron experiments CDF and D0 at Fermilab are summarised and combined. The CDF Run-0 (1988-1889) and Run-I (1992-1995) results have been re-averaged using the BLUE method and combined with Run-I D0 results and the latest published results from CDF taken from the first period of Run-II (2001-2004). The results are corrected to have consistency between the parton distribution functions and electroweak parameters. The resulting Tevatron averages for the mass and total decay width of the W bo…
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 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.…
The results on the measurements of the top-quark mass, based on the data collected by the Tevatron experiments CDF and DO at Fermilab during Run I from 1992 to 1996, are summarized. The combination of the published results, taking correlated uncertainties properly into account, is presented. The resulting world average for the mass of the top quark is: $M_t = 178.0 \pm 4.3 GeV/c^2$, where the total error of consists of a statistical part of $2.7 GeV/c^2$ and a systematic part of $3.3 GeV/c^2$.
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 750/pb of data. Taking correlated uncertainties properly into account the resulting preliminary world average mass of the top quark is Mt=172.5 +/- 1.3(stat) +/- 1.9(syst) GeV/c2, which corresponds to a total uncertainty of 2.3 GeV/c2. The top-quark mass is now known with a precision of 1.3% - a 20% improvement relative to the previous combination.
The results on the measurements of the top-quark mass, based on the data collected by the Tevatron experiments CDF and DØat Fermilab during {\RunI} from 1992 to 1996 and {\RunII} since 2001, are summarized. The combination of the published {\RunI} and preliminary {\RunII} results, taking correlated uncertainties properly into account, is presented. The resulting preliminary world average for the mass of the top quark is: $\MT=172.7\pm 2.9 \GeVc2$, where the total error consists of a statistical part of $1.7 \GeVc2$ and a systematic part of $2.4 \GeVc2$. Compared to the combination prepared for…
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 precise published and preliminary Run II (2001-present) measurements using up to 5.8 fb-1 of data, adding new analyses (the Met+Jets analysis) and updating old ones. Taking uncertainty correlations into account, and adding in quadrature the statistical and systematic uncertainties, the resulting preliminary Tevatron average mass of the top quark is M_T=173.2+/-0.9 GeV/c^2.
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 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 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 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 summarize the published top-quark mass measurements from the CDF and DO experiments at Fermilab. We combine published Run-I (1992-1996) measurements with the most recent published Run-II (2001-present) measurements using up to 340 pb of data. Taking correlated uncertainties properly into account the resulting mass of the top quark is m(top)=174.2 +- 2.0(stat) +- 2.6(syst) GeV/c^2, which corresponds to a total uncertainty of 3.3 GeV/c^2, i.e. 1.9% precision. Since this combination uses only a subset of the available analyses and data sets, it does not supersede our latest world average combi…
We summarize the current top quark mass ($m_t$) measurements from the CDF and D0 experiments at Fermilab. We combine published results from Run I (1992--1996) with the most precise published and preliminary Run II (2001--2011) measurements based on $p\bar{p}$ data corresponding to up to $9.7\:{\rm fb}^{-1}$ of $p\bar{p}$ collisions. Taking correlations of uncertainties into account, and combining the statistical and systematic contributions in quadrature, the preliminary Tevatron average mass value for the top quark is $m_t = 174.30 \ \pm 0.65\:\mathrm{GeV}/c^{2}$, corresponding to a relative …
We present the latest combination of searches for a standard model (SM) Higgs boson in ppbar collisions at \sqrts= 1.96 TeV recorded by the CDF~II detector at the Fermilab Tevatron. Using data corresponding to 2.3-5.9 fb-1 of integrated luminosity, we perform searches in a number of different production and decay modes and then combine them to improve sensitivity. No excess in data above that expected from backgrounds is observed; therefore, we set upper limits on the production cross section times branching fraction as a function of the SM Higgs boson mass (mH). The combined observed (expecte…
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 3.6 fb-1 of data per experiment. Taking correlated uncertainties properly into account the resulting preliminary world average mass of the top quark is Mt = 173.1 +/- 0.6 (stat.) +/- 1.1 (syst.) GeV/c2, assuming Gaussian systematic uncertainties. Adding in quadrature yields a total uncertainty of 1.3 GeV/c2, corresponding to a relative precision of 0.75% on the top-quark mass…
We combine the results of CDF and DO searches for the rare decays B_s to mu+ mu- and B_d to mu+ mu-. The experiments use 364 pb-1 and 300 pb-1 of data respectively. The limits on the branching ratios are obtained by normalizing the estimated sensitivity to the decay B+ to J/psi K+, taking into account the fragmentation ratios f_u/f_s(d). The combined results exclude branching ratios of BR(B_s to mu+ mu-) > 1.5x10-7 and BR(B_d to mu+ mu- > 4.0x10-8 at 95% confidence level. These are the most stringent limits on these decays at the present time.
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$^{-1}$.
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.
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 results based on 1992-95 data (Run 1) from the CDF and DO experiments on the measurements of the W boson mass and width are presented, along with the combined results. We report a Tevatron collider average M_W = 80.456 +- 0.059 GeV. We also report the Tevatron collider average of the directly measured W boson width Gamma_W = 2.115 +- 0.105 GeV. We describe a new joint analysis of the direct W mass and width measurements. Assuming the validity of the standard model, we combine the directly measured W boson width with the width extracted from the ratio of W and Z boson leptonic partial cross…
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.
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.
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.
We discuss recent results obtained by the D0 experiment at the Fermilab Tevatron $p\bar p$ collider and recent combinations of CDF and D0 measurements. Regarding the top quark mass, we present recent measurements obtained at D0, the final Run~I+Run~II D0 combination, as well as the preliminary Run~I+Run~II CDF+D0 combination. We also discuss the combination of the CDF+D0 measurements of the $p\bar p \to t\bar t$ forward-backward asymmetry. We present the first measurement of the direct CP-violating charge asymmetry in $B^\pm$ mesons decaying to $μ^\pm D^{0} X$, and discuss the status of the re…
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 precise published and preliminary Run II (2001-present) measurements using up to 5.6fb-1 of data. Taking uncertainty correlations properly into account, and adding in quadrature the statistical and systematic uncertainties, the resulting preliminary Tevatron average mass of the top quark is M(top) = 173.3+-1.1.
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.
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.
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.
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…
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 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 report on recent measurements of the top quark mass using t t-bar candidate events selected in ~320/pb of data from the "Run II" operation period of the Tevatron p p-bar collider. More emphasis is given on the best single measurement to date Mtop = 173.5 +3.9 -3.8 GeV/c^2, provided by CDF using the "lepton plus jets" channel, where one W decays to a lepton-neutrino pair and the other into quarks (top quarks decay to Wb almost 100% of the time).
We present a summary of top quark physics results from Run 1 at CDF using the Run 1 data sample of 106 pb$^{-1}$. In addition to the precursory measurements of the top quark mass and $\ttbar$ cross section, we have performed a number of other analyses which test the consistency of the $\ttbar$ data sample with the standard model (SM). Deviations from SM expectations could provide hints for new physics. We find that the data are consistent with the SM. While the Run 1 data are statistically limited, we have shown that the systematic uncertainties are under control and thus have layed the ground…
The top quark is by far the most massive fundamental particle observed so far, and the study of its properties is interesting for several reasons ranging from its possible special role in electroweak symmetry breaking to its sensitivity to physics beyond the Standard Model. We present recent top physics results from CDF based on 160-320 inverse pb of ppbar collision data at a center-of-mass energy of 1.96 TeV. The ttbar cross section and the top mass have been measured in different decay channels and using different methods. We have searched for evidence of single top production, setting upper…
The CDF Collaboration has analyzed 955/pb of CDF II data to search for electroweak single top quark production at the Tevatron. We employ three different analysis techniques to search for a single top signal: multivariate likelihood functions; neural networks; the matrix element analysis technique. The sensitivities to a single top signal at the rate predicted by the Standard Model are 2.1 - 2.6 sigma. The first two analyses observe a deficit of single top-like events and set upper limits on the production cross section. The matrix element analysis observes a 2.3 sigma single top excess and me…
We present the most recent measurements of top quark pairs production and top quark properties in proton-antiproton collisions with center-of-mass energy of 1.96 TeV using CDF II detector at the Tevatron. The combination of top pair production cross section measurements and the direct measurement of top quark width are reported. The test of Standard Model predictions for top quark decaying into $b$-quarks, performed by measuring the ratio $R$ between the top quark branching fraction to $b$-quark and the branching fraction to any type of down quark is shown. The extraction of the CKM matrix ele…
We present a measurement of the mass of the top quark from proton-antiproton collisions recorded at the CDF experiment in Run II of the Fermilab Tevatron. We analyze events from the single lepton plus jets final state ($t\bar t\to W^+bW^-\bar b\to lνb q \bar q'\bar b$). The top quark mass is extracted using a direct calculation of the probability density that each event corresponds to the $t\bar t$ final state. The probability is a function of both the mass of the top quark and the energy scale of the calorimeter jets, which is constrained {\it in situ} by the hadronic $W$ boson mass. Using 16…
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…
After an introduction on the peculiarities of flavor-physics measurements at a hadron collider, and on the upgraded Collider Detector at Fermilab (CDF II), I show recent results on two-body B0 and B0s decays into charged, pseudo-scalar, charmless mesons or into muons, to illustrate how the flavor physics program at CDF is competitive with (in B0 decays) and complementary (in B0s decays) to B-factories. Results shown include the new measurement of the CP-violating asymmetry in B0-->K+pi- decays, the first measurement of the time-evolution of B0s-->K+K- decays, and the world best limits on the d…
We present combined results on the search for neutral supersymmetric Higgs bosons with data collected at the CDF and D0 experiments. Data were collected in proton-antiproton collisions at sqrt(s) = 1.96 TeV during Run II of the Tevatron. The searches considered cover the main production and decay mechanisms for Higgs bosons in tau lepton and bottom quark final states. The resulting combination is interpreted in the context of different scenarios within the Minimal Supersymmetric Standard Model.
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 measurements of the top quark mass using the \mT2, a variable related to the transverse mass in events with two missing particles. We use the template method applied to t\tbar dilepton events produced in p\pbar collisions at Fermilab's Tevatron and collected by the CDF detector. From a data sample corresponding to an integrated luminosity of 3.4 \invfb, we select 236 t\tbar candidate events. Using the \mT2 distribution, we measure the top quark mass to be M_{Top} = 168.0^{+4.8}_{-4.0} $\pm$ {2.9} GeV/c^{2}. By combining the \mT2 with the reconstructed top mass distributions based on…
We measure the polarization of W bosons from top-quark (t) decays into final states with a charged lepton and jets, tt --> WbWb --> lvbqqb, using the full Run II data set collected by the CDF II detector. A model-independent method simultaneously determines the fraction of longitudinal (f_0) and right-handed (f_+) W bosons to yield f_0 = 0.726 +/- 0.066 (stat) +/- 0.067 (syst) and f_+ = -0.045 +/- 0.044 (stat) +/- 0.058 (syst) with a correlation coefficient of -0.69. Additional results are presented under various standard model assumptions. No significant discrepencies with the standard model …
We present a measurement of the top-quark mass using a sample of $t\bar{t}$ events in 5.7 fb$^{-1}$ of integrated luminosity from $p\bar{p}$ collisions at the Fermilab Tevatron with $\sqrt{s} =$ 1.96 TeV and collected by the CDF II Detector. We select events having no identified charged leptons, large missing transverse energy, and four, five, or six jets with at least one jet tagged as coming from a $b$ quark. This analysis considers events from the semileptonic \ttbar decay channel, including events that contain tau leptons. The measurement is based on a multidimensional template method. We …
Twelve years after the discovery of the Top quark, the CDF detector has collected large samples of tt-bar events with integrated luminosities up to 1-1.7 fb^-1, where we are able to probe our knowledge of the Standard Model Top quark. This article will focuss on those analysis results dedicated to find new physics in the Top quark production: measurement of relative fractions of Top pair production mechanisms, searches for a massive resonant state decaying to tt-bar pairs as well as a heavy Top-like quark decaying as the Standard Model Top quark. Besides its production, the Top quark decay is …
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…
