Narrow Results

The 1992–1995 running of the Fermilab Tevatron (the so-called Run I) ended with many important physics goals accomplished, including the discovery of the top quark, and the anticipation of many further questions to be answered in the future. After many upgrades to the detector and to the accelerator complex, Run II began in April 2001. First results obtained by the Collider Detector at Fermilab (CDF) collaboration from the analysis of early Tevatron Run II data are reported here. They fall into two categories: a number of measurements have been performed with the primary goal of establishing detector performance and physics potential. Another set of measurements make use of completely new capabilities of the upgraded detector, thus allowing for competitive results with a modest amount of integrated luminosity.

The search for neutral resonances at the energy frontier has a long and illustrious history, resulting in multiple discoveries. The canonical search scans the reconstructed invariant mass distribution of identified fermion pairs. Two recent analyses from the CDF experiment at the Fermilab Tevatron have applied novel methods to resonance searches. One analysis uses simulated templates to fit the inverse mass distribution of muon pairs, a quantity with approximately constant resolution for momenta measured with a tracking detector. The other analysis measures the angular distribution of electron pairs as a function of dielectron mass, gaining sensitivity over a probe of the mass spectrum alone. After reviewing several models that predict new neutral resonances, we discuss these CDF analyses and potential future applications.

Some theories of particle physics are so compelling that it is worth doing a comprehensive and systematic set of experimental searches to see if they are realized in nature. Supersymmetry is one such theory. This review focuses on the motivation for a broad set of cosmology-inspired search strategies at the Tevatron and on their implementation and results at the Collider Detector at Fermilab (CDF) with the first few fb^-1 of integrated luminosity of data.

This review presents the world's most precise measurement of the W-boson mass m_W using data corresponding to ≈ 2.2 fb^-1 integrated luminosity collected with the CDF II detector at Fermi National Accelerator Laboratory (Fermilab). With samples of 470,126 W → eν candidates and 624,708 W → μν candidates, m_W is measured to be 80387±12_stat ± 15_syst = 80387 ± 19 MeV [Phys. Rev. Lett.108, 151803 (2012)]. This result significantly exceeds the precision of all previous measurements and improves the world averaged precision by 30%.

Recent measurements in the top quark sector at the Fermilab Tevatron collider are discussed. Measurements at the Tevatron use up to 9.7 fb^-1 of data corresponding to the full data sets recorded by each of the experiments, CDF and DØ. This review discusses the most recent measurements of inclusive and differential top quark cross-sections in strong and electroweak production of top quarks and related measurements, as well as measurements of angular distributions related to asymmetries in top quark production. Furthermore, the current status of precision measurements of the mass of the top quark is discussed. Where available, combinations of CDF and DØ results are presented.

We present measurements of the production cross section in b-tagged lepton + jets events from 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 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 sample, with two secondary vertex tagged jets, yields a production cross section consistent with the inclusive measurements. Results are consistent with a Standard Model signal and current measurements of the top quark mass.

We measure the mass of the top quark using 162 pb^-1 of data collected by the CDF experiment at the Fermilab Tevatron in Run II. The decay chain is studied using a novel technique called the Multivariate Template Method (MTM). Using this technique we obtain a result of for the top quark.

Using almost twice the luminosity of Run I, we present preliminary results on di-boson final states production at the Tevatron. These results include cross section measurements of most di-boson final states including the first measurement of WW cross section.

We present the prospects of searches for neutral, long-lived particles which decay to photons using their time of arrival measured with a newly installed EMTiming system at CDF. Using GMSB models we estimate the expected 95% confidence level exclusion regions as a function of the neutralino mass and lifetime. We find that a combination of single photon and diphoton analyses should allow the Tevatron in run II to easily extend the exclusion regions from ALEPH at LEP II, and cover parts of the theoretically favored GMSB parameter space.

The Collider Detector at Fermilab Collaboration has analyzed events with two photons in the central detector. The cross section is measured and compared to theoretical models. The diphoton mass spectrum is searched for anomalous narrow peaks and a search for gauge–mediated SUSY is performed with events with two photons and missing E_t.

We present the results of a search for a neutral MSSM Higgs boson decaying to a pair of tau leptons. The analyzed data sample corresponds to integrated luminosity of approximately 200 pb^-1 of collisions at . It was collected by the CDF detector during Run 2 of the Fermilab Tevatron. We select tau pairs in which one of the taus decays hadronically and the other to e or μ and neutrinos. We see no evidence of signal and perform a fit to the (partially) reconstructed di-tau mass to set limits on the product of Higgs production cross-section and its branching fraction to taus.

The CDF Collaboration has made a preliminary measurement of B_d mixing as a first step toward measuring mixing in the B_s system. Flavor tagging using opposite-side jets and muons as well as same-side tagging schemes have been applied. Results agree well with precise results from the B-factories. We use these results to estimate CDF's B_s mixing range using the present data set (~250pb^-1) and extrapolate to the potential from larger data sets in future running.

Relative branching fractions of decays (where h, h′ = K or π) and the direct CP asymmetry in the mode are measured with 179 ± 11 pb^-1 of data collected at using the CDF II detector at the Fermilab Tevatron collider. The first branching-fraction measurement of a meson to two pseudoscalars, , and a search for the baryon mode are also presented, in addition to branching-fraction limits on the rare channels , , and .

The understanding of the dynamics behind the breaking of the electroweak symmetry is one of the most important goals in the field of high energy physics. In the Standard Model (SM) Higgs mechanism plays a key role in the symmetry breaking, one manifestation of which is spin-0 Higgs boson. Thus the search for the Higgs boson is one of the flag-ship analyses at the Tevatron. Over the past few years the CDF experiment has made significant improvements in its sensitivity on the search for the SM Higgs boson. In this paper we summarize CDF's most recent results on the searches for the SM Higgs boson production at the Tevatron using data samples of integrated luminosities up to 3 fb^-1. We also present the Tevatron's latest combined results on the SM Higgs boson search, and discuss the possibility that it could be found at the Tevatron in the near future.

We present the results of direct searches for the Standard Model Higgs boson at the Tevatron. Results are derived from the complete Tevatron Run II dataset, with a measured integrated luminosity of 10 fb^-1 of proton–antiproton data. The searches are performed for assumed Higgs masses between 90 and 200 GeV/c². We observe an excess of events in the data compared with the background predictions, which is most significant in the mass range between 115 and 135 GeV/c², consistent with the Higgs-like particle recently observed by ATLAS and CMS. The largest local significance is 2.7 standard deviations, corresponding to a global significance of 2.2 standard deviations. We also combine separate searches for and H→W⁺W^-, and find that the excess is concentrated in the channel, although the results in the H→W⁺W^- channel are still consistent with the possible presence of a low-mass Higgs boson.

As one of the most important parameters in the Standard Model (SM), the mass of the W boson (m_W) is currently the limiting factor in our ability to tighten the constraint on the mass of the Higgs boson (m_H) within the SM framework. This review summarizes the world's most precise m_W measurement to date using ~2.2 fb^-1 data collected in collisions at with the CDF II detector at the Fermilab Tevatron Collider. This review will first describe the motivation for improving the precision of m_W measurement, then present the details of this analysis, followed by the final measurement result and the future perspective.

This review summarizes the recent results for top quark and Higgs boson measurements from experiments at Tevatron, a proton–antiproton collider at a center-of-mass energy of , and the Large Hadron Collider, a proton–proton collider at a center-of-mass energy of . These results include the discovery of a Higgs-like boson and measurement of its various properties, and measurements in the top quark sector, e.g. top quark mass, spin, charge asymmetry and production of single top quark.

We present a review of heavy flavor physics results from the CDF and DØ Collaborations operating at the Fermilab Tevatron Collider. A summary of results from Run 1 is included, but we concentrate on legacy results of charm and b physics from Run 2, including results up to Summer 2014.

We present results on top quark physics from the CDF and D0 collaborations at the Fermilab Tevatron collider. These include legacy results from Run II that were published or submitted for publication before mid-2014, as well as a summary of Run I results. The historical perspective of the discovery of the top quark in Run I is also described.

We review the techniques and results of the searches for the Higgs boson performed by the two Tevatron collaborations, CDF and DØ. The Higgs boson predicted by the Standard Model was sought in the mass range 90 GeV < m_H < 200 GeV in all main production modes at the Tevatron: gluon–gluon fusion, WH and ZH associated production, vector boson fusion, and production, and in five main decay modes: , H→τ⁺τ^-, H→WW^(*), H→ZZ^(*) and H→γγ. An excess of events was seen in the searches consistent with a Standard Model Higgs boson with a mass in the range 115 GeV < m_H < 135 GeV. Assuming a Higgs boson mass of m_H = 125 GeV, studies of Higgs boson properties were performed, including measurements of the product of the cross section times the branching ratio in various production and decay modes, constraints on Higgs boson couplings to fermions and vector bosons, and tests of spin and parity. We also summarize the results of searches for supersymmetric Higgs bosons, and Higgs bosons in other extensions of the Standard Model.