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 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…
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.
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$^{-1}$.
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.
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.
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.
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.
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 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 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.
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.
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.
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.
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 report an evidence of \textit{s}-channel single top quark production in $p\bar{p}$ collision at $\sqrt{s}= 1.96 \mathrm{TeV}$ using data with integrated luminosity of $9.4 \mathrm{fb}^{-1}$ collected by the Collider Detector at Fermilab (CDF). We select events with one charged lepton, large missing transverse energy and two bottom quark jets. The observed significance of the result is 3.8 standard deviation from background only prediction. We measure the inclusive cross section to be $1.41^{+0.44}_{-0.42}\mathrm{(stat+syst)} \mathrm{pb}$ assuming $m_t = 172.5 \mathrm{GeV}/c^2$.
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 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 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 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 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…
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%.
The forward-backward charge asymmetry ($A_{FB}$) of $\ppbar \to e^{+}e^{-} X$ is sensitive to the vector and axial-vector couplings of the initial state quarks and final state leptons. Based on the measurement in $72 pb^{-1}$ of CDF Run II data, we measure the coupling constants of the $Z$ boson to quarks and electron. The electroweak mixing angle, $\sin^2θ_{W}$, is also measured through its relation to the coupling constants.
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 …
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 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.
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 %.
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 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 $2.8 \GeVc2$.
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…
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 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 …
With growing datasets collected by the CDF II experiment, studies of the spectroscopy of mesons containing heavy quarks become more exciting. The CDF experiment has good capabilities in both charm and bottom sector. This capability allowed also to contribute to the study of the zoo of states called X,Y,Z. In this area we present a recent update of the mass measurement of X(3872). The result m(X(3872)) = 3871.61 +- 0.16 +- 0.19 MeV is currently the most precise measurement in the world. In addition, we report evidence for a new narrow resonance, Y(4140), the first to be seen in the J/psi phi de…
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…
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 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 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…
We report a measurement of the top quark mass $M_t$ in the dilepton decay channel $t\bar{t}\to b\ell'^{+}ν'_\ell\bar{b}\ell^{-}\barν_{\ell}$. Events are selected with a neural network which has been directly optimized for statistical precision in top quark mass using neuroevolution, a technique modeled on biological evolution. The top quark mass is extracted from per-event probability densities that are formed by the convolution of leading order matrix elements and detector resolution functions. The joint probability is the product of the probability densities from 344 candidate events in 2.0 …
Recent measurements of the mass of the top quark are presented using 162 pb-1 of data of ppbar collisions at sqrt(s)=1.96 TeV collected by the CDF detector at the Tevatron collider during Run II. The analyses focus on the semi-leptonic decay mode with one or two identified bottom quarks. The Template Method reconstructs the invariant mass of the top quark in each event. The Multivariate Template Method enhances this approach by adding information on the event topology. The Dynamical Likelihood Method discriminates between possible mass values using top quark decay observables and attempts to u…
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 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…
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 results of recent searches for new physics using the CDF detector at the Fermilab Tevatron. Presented are searches for Higgs -> gammagamma, as well as more general searches in gammagamma + X where X is missing Et, jets, charged leptons, b-quarks or extra photons. The CDF eegammagamma-mett candidate event is discussed along with estimates of the expected rates in the Standard Model. Other searches for SUSY, Higgs and Technicolor look for particles which decay to vector bosons and b-quarks.
We review the most recent measurements of the top quark mass using data collected by the CDF experiment at the Tevatron 1.96 TeV ppbar collider. The mass measurements are performed in all main decay modes of the produced ttbar pairs using integrated luminosities up to 2fb-1. In most channels the total uncertainty is dominated by systematic effects, most of which are currently being revised. The precise measurement of the top quark mass is one of the Tevatron's main and long lasting legacies. Besides serving as a benchmark measurement at the LHC collider, it will serve as a consistency check of…
We present a measurement of the top quark mass in the lepton+jets and dilepton channels of $t\bar{t}$ decays using the template method. The data sample corresponds to an integrated luminosity of 5.6 fb$^{-1}$ of $p\bar{p}$ collisions at Tevatron with $\sqrt{s}=1.96$ TeV, collected with the CDF II detector. The measurement is performed by constructing templates of three kinematic variables in the lepton+jets and two kinematic variables in the dilepton channel. The variables are two reconstructed top quark masses from different jets-to-quarks combinations and the invariant mass of two jets from …
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 a measurement of the top quark mass using events collected by the CDF II Detector from ppbar collisions at \sqrt{s} = 1.96 TeV at the Fermilab Tevatron. We calculate a likelihood function for the top mass in events that are consistent with ttbar->bbar l^- \nubar b l^+ νdecays. The likelihood is formed as the convolution of the leading-order matrix element and detector resolution functions. The joint likelihood is the product of likelihoods for each of 33 events collected in 340 pb^{-1} of integrated luminosity, yielding a top quark mass M_t = 165.2 +- 6.1 (stat.) +- 3.4(syst.) GeV/c^…
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 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 present a measurement of the top-quark mass, $M_{\mathrm{top}}$, in the all-hadronic decay channel $t\bar{t} \to W^+b W^- \bar{b} \to q_1\bar{q}_2 b q_3 \bar{q}_4 \bar{b}$. The analysis is performed using 310 pb$^{-1}$ of $\sqrt{s}$=1.96 TeV $p\bar{p}$ collisions collected with the CDF II detector using a multi-jet trigger. The mass measurement is based on an event-by-event likelihood which depends on both the sample purity and the value of the top-quark mass, using 90 possible jet-to-parton assignments in the six-jet final state. The joint likelihood of 290 selected events yields a value o…
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…
If the Technicolor omega_T particle exists, a likely decay mode is omega_T -> gamma pi_T, followed by pi_T -> bb-bar, yielding the signature gamma bb-bar. We have searched 85 pb^-1 of data collected by the CDF experiment at the Fermilab Tevatron for events with a photon and two jets, where one of the jets must contain a secondary vertex implying the presence of a b quark. We find no excess of events above standard model expectations. We express the result of an exclusion region in the M_omega_T - M_pi_T mass plane.
We present a measurement of the top-quark mass using the full data set of Tevatron $\sqrt{s} = 1.96$ TeV proton-antiproton collisions recorded by the CDF II detector, corresponding to an integrated luminosity of \invfb{8.7}. The analysis uses events with one semileptonic $t$ or $\bar{t}$ decay, but without detection of the electron or muon. We select events with significant missing transverse energy and multiple jets. We veto events containing identified electrons or muons. We obtain distributions of the top-quark masses and the invariant mass of the two jets from $W$-boson decays from data an…
We report on the first search for top-quark production via flavor-changing neutral-current (FCNC) interactions in the non-standard-model process u(c)+g -> t using ppbar collision data collected by the CDF II detector. The data set corresponds to an integrated luminosity of 2.2/fb. The candidate events feature the signature of semileptonic top-quark decays and are classified as signal-like or background-like by an artificial neural network trained on simulated events. The observed discriminant distribution is in good agreement with the one predicted by the standard model and provides no evidenc…
The latest CDF and D0 experiment measurements of the top quark properties except the top quark mass are presented. The final combination of the CDF and D0 forward-backward asymmetry measurements is shown together with the D0 measurements of the inclusive top quark pair cross-section as well as the top quark polarization.
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 report a measurement of the top quark mass, M_t, in the dilepton decay channel of $t\bar{t}\to b\ell'^{+}ν_{\ell'}\bar{b}\ell^{-}\barν_{\ell}$ using an integrated luminosity of 1.0 fb^{-1} of p\bar{p} collisions collected with the CDF II detector. We apply a method that convolutes a leading-order matrix element with detector resolution functions to form event-by-event likelihoods; we have enhanced the leading-order description to describe the effects of initial-state radiation. The joint likelihood is the product of the likelihoods from 78 candidate events in this sample, which yields a mea…
From a study of the X(3872) mass and width based on the world's largest sample of $X(3872)\to J/ψπ^+π^-$ decays, we find that our X(3872) signal is consistent with a single state, and leads to the most precise measurement of the X(3872) mass. We also report the recent evidence for a new narrow structure, Y(4140), decaying to the $J/ψϕ$ final state, in exclusive $B^+\to J/ψϕK^+$ decays in a data sample corresponding to an integrated luminosity of 2.7 \ifb collected at the CDF II detector. This narrow structure with its mass well above open charm pairs is unlikely to be a candidate for a convent…
