In this note we present the results of several searches for physics beyond the standard model. All final states use 2 inverse fb\of data produced at Tevatron in p-pbar collisions at 1.96 TeV and collected by the CDF Run II detector. None of the analysis is heavily optimized for any specific model. All signatures contain missing transverse energy in the final state and all, except for one, have at least one photon in the final state. Unfortunately, no interesting excesses of events over the SM prediction are observed in any final states, except may be for the last one.
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.
Recent searches for dijet, dielectron, and dimuon resonances by the CDF Collaboration are presented. No evidence for a signal is found in any channel, so 95% confidence level upper limits are set on the new particle production.
A brief review of searches for physics beyond the Standard Model with photons using the CDF detector at the Tevatron is given here. These include searches for supersymmetry, extra dimensions, excited electrons and W/Z$+γ$ production, as well as anomalous photon production. Recent results from CDF Run II experiment is presented, but some results from Run I are also reviewed.
We present the latest CDF searches for the Standard Model Higgs boson with 1.96 TeV center-of-mass energy collisions produced at the Fermilab Tevatron. The data was collected with the CDF II detector at the Tevatron collider and correspond to an integrated luminosity from 2 to 4.8 1/fb. To achieve maximal sensitivity, many channels are analyzed including final states from gluon fusion, vector boson fusion, and associated production with W and Z bosons.
We present results of searches for new physics in final states with photons at CDF in approximately 1 fb-1 of ppbar collisions at 1.96 TeV. We give an overview of the data-driven photon background estimation techniques used for the analyses. We report on a search for diphoton peaks and signature-based searches for diphoton+X, lepton+photon+X (X = electron, muon, missing transverse energy, photon) and ttbar+photon.
We present the most recent results on searches for squarks and gluinos in ppbar collisions at sqrt(s)=1.96 TeV, in events with large missing transverse energy, leptons and multiple jets in the final state, based on 1.8 to 2.8 fb-1 of data collected by the CDF Run II detector at the Tevatron. No evidence of new physics is found and exclusion limits in several MSSM scenarios are extracted.
The addition of the EMTiming system installed to provide the time measurements of the electromagnetic calorimeter signals has significantly increased the sensitivity of CDF to events with a photon and a missing energy. Here I review recent searches in this signature performed by CDF using data from proton-antiproton collisions at the center of mass energy of 1.96 TeV. They provide new constraints on models with large extra dimensions and with gauge mediated supersymmetry breaking.
Results are presented on searches for standard model and non-standard model production of a Higgs boson in pbar-p collisions at sqrt{s}= 1.96 TeV with the CDF II detector at the Fermilab Tevatron. Using data corresponding to 2-3.6 1/fb of integrated luminosity, searches are performed in a number of different production and decay modes. 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 Higgs boson mass.
Recently there has been revival of interest in exotic baryon spectroscopy triggered by experimental evidence for pentaquarks containing u,d,s and c-quarks. We report results of the searches for pentaquark states in decays to p K0S, Xi- pi+,- and D*- p performed at CDF detector using 220 pb-1 sample of pp= interactions at sqrt(s) of 1.96 TeV. No evidence for narrow resonances were found in either mode.
Experimental results of a search for the Xi_(3/2)(1860) cascade pentaquark state in data collected with the CDF 2 Detector in Run II at the Tevatron are presented. No evidence for these states in the neutral Xi-pi+ and doubly charged Xi-pi- modes has been found. Preliminary upper limits on yields at 1862 MeV/c**2 relative to the well established resonance Xi*0(1530) are presented.
This contribution reports on preliminary measurements on searches for squarks and gluinos at CDF and DØdetectors in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV. The analyses are performed using event topologies with multiple jets and large missing energy in the final state. The mSUGRA scenario and R-parity conservation is assumed. No excess with respect to the Standard Model predictions is observed and new limits on the gluino and squark masses are extracted.
We present the most recent results of searches for physics beyond the Standard Model using the CDF and D0 detector in the contest of Supersymmetry (SUSY) with Supergravity (SUGRA) constraints. All results described correspond to analysis performed using the past 1992-1996 Fermilab Tevatron Run I data (roughly 110pb-1 per each experiment). In particular we report on searches for stop decay in tau channel assuming R-Parity violation; searches for R-Parity Violating LSP decays in di-muon plus 4 jets channel; searches for resonant slepton production in R-Parity Violating mSUGRA; searches for mSUGR…
We present the current status of searches for physics beyond the Standard Model at the Tevatron 1.96-TeV proton-antiproton collider using data collected with the CDF experiment. We cover searches for supersymmetry, extra dimensions and new gauge bosons.
We present the results of searches for the standard model Higgs boson at CDF in final states with bottom quarks. Results are derived from the complete Tevatron Run II dataset, with a measured integrated luminosity of 9.5 fb$^{-1}$ of proton-antiproton data. The searches are performed for assumed Higgs masses between 90 and 150 GeV, for Higgs bosons produced in association with W or Z bosons. Employing several improved techniques, these are currently the most sensitive searches in the world for these processes, surpassing previous CDF results by 30% beyond what would be expected from the additi…
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…
The CDF experiment at the Tevatron $p\bar{p}$ collider has pioneered and established the role of hadron collisions in exploring flavor physics through a broad program that is now at its full maturity. We report new results sensitive to physics beyond the standard model, obtained using the whole CDF data set; including new bounds on the \Bs\ mixing phase and the decay width difference of \Bs\ mass-eigenstates and a measurement of the difference of CP asymmetries in $K^+K^-$ and $π^+π^-$ decays of $D^0$ mesons. We also present a new measurement of the $\Bs \rightarrow D^{(*)+}_s D^{(*)-}_s$ bran…
We present recent results of searches for exotic photons at CDF II. In the first signature-based search, we search for anomalous production of two photons with additional energetic objects. The results are consistent with the standard model expectations. In the second analysis, we present a signature-based search for anomalous production of events containing a photon, two jets, of which at least one is identified as originating from a $b$ quark, and missing transverse energy. We find no indications of non-standard model phenomena. Finally, a search for a fermiophobic Higgs in the diphoton fina…
In the last decade the CDF experiment at the Tevatron clearly demonstrated that it is possible to study extensively heavy flavour physics in hadron collisions and achieve remarkable results, competitive and complementary to $B$-factories. In this paper we report on the indirect searches for physics beyond the standard model via measurements of rare $b$-hadron decays. The final limits, based on the analysis of the full CDF data set, on the branching fraction of the $B^0_{(s)}$ decay into a pair of muons are presented and discussed. Moreover we review the latest measurements, with 6.8 fb$^{-1}$ …
We present the development and validation of the Higgs Optimized b Identification Tagger (HOBIT), a multivariate b-jet identification algorithm optimized for Higgs boson searches at the CDF experiment at the Fermilab Tevatron. At collider experiments, b taggers allow one to distinguish particle jets containing B hadrons from other jets; these algorithms have been used for many years with great success at CDF. HOBIT has been designed specifically for use in searches for light Higgs bosons decaying via H ! b\bar{b}. This fact combined with the extent to which HOBIT synthesizes and extends the be…
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 the non-standard model Higgs boson searches at both DO and CDF experiments. We concentrate on three topics, reported by DO and CDF recently: the searches for the minimal supersymmetric Higgs boson using pp--> hbb --> bbbb and pp --> hX --> tau tau X, and for long-lived doubly charged Higgs boson.
The Run I results on the searches for new physics in photon final states were intriguing. The rare 2 electrons + 2 photons + missing transverse energy (MET) candidate event and the measured event rate for the signature lepton + photon + MET, which was 2.7 sigma above the Standard Model predictions, sparked signature-based searches in the photon + photon + X and lepton + photon + X channels. With more data in Run II we should be able to answer a simple question: was it an anomaly or were the Run I results the first evidence for the new physics? We present searches for New Physics in Photon Fina…
Recent results of searches for new physics in top events at the Tevatron are presented. In case of CDF three searches are discussed using 6.0 to 8.7 fb^{-1} of data, with the latter being the final CDF data sample available for this kind of analysis. CDF carried out a search for Top + jet resonance production, dark matter production in association with single top and boosted tops. No signs of new physics are observed and instead upper limits are derived. DØ used 5.3 fb^{-1} of data and searched for a narrow resonance in ttbar production and a time dependent ttbar cross section, which would rev…
A summary of the results of several recent studies of charm mixing is presented. A number of different methods were used, including the measurement of lifetime ratios for final states of different CP, time dependence of wrong-sign hadronic decays, fits to time-dependent Dalitz plots, and searches for wrong-sign semi-leptonic decays. Taken together, they suggest mixing is of order 1%. The status of searches for indirect CP violation is also reported.
At the Fermilab Tevatron, the CDF detector is used to study diboson production in $p\bar{p}$ collisions at $\sqrt{s}$ = 1.96 TeV. We report recent diboson production measurements, limits on anomalous triple gauge couplings and latest results from semi-leptonic diboson searches.
The CDF and DØ experiments at the Tevatron are currently the only capable of searching for the Standard Model Higgs boson. This article describes their most sensitive searches in the expected Higgs mass range, focusing on advanced methods used to extract the maximal sensitivity from the data. CDF presents newly updated results for $H \to W^+W^-$ and $ZH \to l^+l^- b\bar{b}$. DØ\ presents two new searches for $WH \to lνb\bar{b}$. These new analyses use the same 1 fb$^{-1}$ dataset as previous searches, but with improved techniques resulting in markedly improved sensitivity.
Quark-quark and quark-lepton searches for compositenss at the Fermilab Tevatron are summarized. These are of the contact-interaction variety where sqrt(s-hat) < the hypothesized mass scales, Lambda. Tevatron experiments limit a variety of compositeness phenomena in the range from 1.9 to 8.3 TeV. These limits result from measurements of: the Ht spectrum (D0), dijet mass (D0), dijet angular distribution (CDF, D0), drell-yan production (CDF, D0), and the Neutral Current to Charged Current ratio (CCFR/NuTeV).
We present the current status of the search for new physics at CDF, using integrated luminosity up to 3.2 fb-1. We cover searches for supersymmetry, extra dimensions, new heavy bosons, and generic dilepton resonances.
We have searched for evidence of physics beyond the standard model in events that include an energetic photon and an energetic b-quark jet, produced in 85pb of ppbar collisions at 1.8 TeV at the Tevatron Collider at Fermilab. This signature, containing at least one gauge boson and a third-generation quark, could arise in the production and decay of a pair of new particles, such as those predicted by Supersymmetry, leading to a production rate exceeding standard model predictions. We also search these events for anomalous production of missing transverse energy, additional jets and leptons (e, …
We present the results of searches for the Standard Model Higgs boson decaying predominantly to WW pairs, at a center-of-mass energy of sqrt(s)=1.96 TeV, using up to 8.2 fb^{-1} of data collected with the CDF and D0 detectors at the Fermilab Tevatron collider. The analysis techniques and the various channels considered are discussed. These searches result in exclusions across the Higgs mass range of 156.5<mH<173.7 GeV for CDF and 161<mH<170 GeV for D0.
The missing transverse energy (MET) plus b-jets signature is very promising for searches for the Higgs boson or new physics. Indeed, MET naturally arises from unidentified particles such as neutrinos, neutralinos, gravitons, etc., and b-quarks are the main decay products of a low mass Higgs boson as well as of several exotic particles. The main challenge is to identify and reject the numerous standard model (SM) backgrounds that mimic this signature. This is especially so for QCD multi-jet production, a large background due to mis-measurement (rather than undetectable particles). We present st…
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.
We present the latest results from the CDF experiment at the Tevatron Collider in \ppbar collisions at $\sqrt{s} = 1.8$ TeV. The large data sample collected during Run 1, from 1992 until 1995, allows measurements in many domains of high-energy physics. Here, we report on the first measurement of $\sin(2β)$, a CP violation parameter, and on an improved measurement of the top quark cross section. We also report on searches for the so-far elusive Higgs boson, and for SUSY, through searches for direct production of top and bottom scalar quarks. Finally, we outline the prospects for the physics dur…
We present a combination of searches for the standard model Higgs boson using the full CDF Run II data set, which corresponds to an integrated luminosity of 9.45--10.0 fb$^{-1}$ collected from $\sqrt{s}=1.96$ TeV $p{\bar{p}}$ collisions at the Fermilab Tevatron. The searches consider Higgs boson production from gluon-gluon fusion, vector-boson fusion, and associated production with either a $W$ or $Z$ boson or a $t{\bar{t}}$ pair. Depending on the production mode, Higgs boson decays to $W^+W^-$, $ZZ$, $b{\bar{b}}$, $τ^+τ^-$, and $γγ$ are examined. We search for a Higgs boson with masses ($m_H$…
We combine the results of searches for the standard model Higgs boson based on the full CDF Run II data set obtained from sqrt(s) = 1.96 TeV p-pbar collisions at the Fermilab Tevatron corresponding to an integrated luminosity of 9.45/fb. The searches are conducted for Higgs bosons that are produced in association with a W or Z boson, have masses in the range 90-150 GeV/c^2, and decay into bb pairs. An excess of data is present that is inconsistent with the background prediction at the level of 2.5 standard deviations (the most significant local excess is 2.7 standard deviations).
Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with respect to the standard model prediction. A model-independent approach (Vista) considers the gross features of the data, and is sensitive to new large cross section physics. A quasi-model-independent approach (Sleuth) searches for a significant excess of events with large summed transverse momentum, and is particularly sensitive to new electroweak scale physics that appears predomi…
We present a method for improving the $b$-jet energy resolution in order to improve the signal sensitivity in searches for particles decaying to a $b$ quark and anti-$b$ quark. A correction function is computed for individual jets, which combines information from the secondary vertex tagger, the offline tracking and standard calorimeter-based jet-energy reconstruction algorithm in order to provide a more accurate measurement of the true $b$-quark energy. We apply the correction to Monte-Carlo-simulated jets in the process $WH \rightarrow \ell νb\bar b$ and find an improvement in both the mean …
We report on searches for the standard model Higgs boson with the CDF and D0 detectors using up to 2.7 fb$^{-1}$ of $\sqrt s=$ 1.96 TeV proton anti-proton collisions at Fermilab's Tevatron. We focus on analyses that are sensitive to low mass Higgs production with $m_H<$ 140 GeV/$c^2$ favored by precision electroweak constraints. Both CDF and D0 find no evidence for Higgs boson production, and set upper limits on cross section times branching ratio. Several analyses improvements have increased the sensitivity to a Higgs signal faster than what is expected from increasing datasets alone.
Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with respect to the standard model prediction. A model-independent approach (Vista) considers the gross features of the data, and is sensitive to new large cross section physics. A quasi-model-independent approach (Sleuth) searches for a significant excess of events with large summed transverse momentum, and is particularly sensitive to new electroweak scale physics that appears predomi…
The CDF and DO experiments have collected and analyzed about 300 inverse picobarns of data during the Run II of the Tevatron. Results of searches for new non supersymmetric particles based on these datasets will be presented.
Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the standard model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a Bump Hunter searches invariant mass distributions for "bumps" that could indicate resonant production of new particles; and the Sleuth procedure s…
Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the Standard Model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a ``Bump-Hunter'' searches invariant mass distributions for ``bumps'' that could indicate resonant production of new particles; and the Sleuth proce…
We present recent CDF results based on approximately 1 fb$^{-1}$ of $p\bar p$ collisions at $\sqrt s = 1.96$ TeV delivered at Fermilab Tevatron. Results shown include the observation of the $B_s$ oscillation frequency, the first observation of bottom baryon $Σ_b^{(*)\pm}$ states, updates on $B$ hadrons lifetimes, and searches for rare decays in the $b\to sμ^+μ^-$ transition and in charmless two-body B decays.
During the past years the CDF and D0 detectors have collected large amounts of data obtaining a relatively pure sample of pair-produced top quarks and a well understood sample containing singly-produced top quarks. These samples have been used for the precise measurement of the top quark properties, and have set stringent limits on new physics in the top sample. This reports presents the latest results from the CDF and D0 collaborations on the search for new physics within the top sample using an integrated data sample of up to 3.6 fb-1.
We present results from CDF and D0 on direct searches for high mass standard model (SM) Higgs boson (H) in ppbar collisions at the Fermilab Tevatron at \sqrt(s) = 1.96 TeV. Compared to previous Higgs boson Tevatron combinations, more data and new channels (H -> W+W- -> lnujj, H -> WW -> l+tau + X and trilepton final states) have been added. Most previously used channels have been reanalyzed to gain sensitivity. Analyzing 5.9 fb^-1 of data at CDF, and 5.4-6.7 fb^-1 at D0, the combination excludes with 95% C.L. a standard model Higgs boson in the mass range of m_H = 158-175 GeV/c2.
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.
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 searches for pair-production of fourth generation tprime quarks in their decays to Wq. We analyse 4.6 fb-1 and 4.3 fb-1 of data collected by the CDF and D0 detectors, respectively, at the Fermilab Tevatron collider at a centre-of-mass energy of sqrt s = 1.96 TeV. We reconstruct the mass of the heavy quark and perform a two-dimensional-fit to the observed (HT, Mreco) distributions to discriminate the new physics signal from standard model backgrounds. As no significant excess of events is observed, we exclude a fourth-generation tprime quark with a mass below 335 (296) GeV at 95%CL a…
In the following, we describe preliminary results of searches for non-SM higgs bosons at the CDF and D0 experiments. Both experiments use data obtained in pp-bar collisions at the Tevatron at sqrt(s)=1.96 TeV.
We combine searches by the CDF and D0 collaborations for a Higgs boson decaying to W+W-. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb-1 of p-pbar collisions at sqrt{s}=1.96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard-model Higgs boson in the mass range 162-166 GeV at the 95% C.L.
Run II at the Tevatron has seen an explosion of results related to the Bs meson, ranging from tests of QCD models, to probes of electro-weak symmetry breaking, to direct searches for new physics effects. I will briefly summarize the CDF and D0 Bs-physics programs, describing the suitability of the detectors for doing this kind of physics, and pointing out how our knowledge of important quantities has improved through Run II measurements.
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.
The top quark, discovered in 1995 by the CDF and D0 collaborations at the Tevatron collider at Fermilab, is the heaviest known elementary particle today. Due to its high mass and short lifetime, the top quark plays a special role in searching for physics beyond the Standard Model. In this article, recent results of searches for new physics in the top sector, performed by CDF and D0, are presented. In particular, we discuss the search for ttbar resonances, for tj resonances, the search for heavy fourth generation quarks, for dark matter produced in association with single tops, the study of ano…
We combine results from the CDF and D0 Collaborations on direct searches for the standard model (SM) Higgs boson (H) in ppbar collisions at the Fermilab Tevatron at sqrt(s)=1.96 TeV. Compared to the previous Tevatron Higgs boson search combination, more data have been included, additional channels have been incorporated, and some previously used channels have been reanalyzed to gain sensitivity. Searches are carried out for hypothesized Higgs boson masses between 100 and 200 GeV/c^2. With up to 10 fb-1 of luminosity analyzed, the 95% C.L. median expected upper limits on Higgs boson production …
We combine results from CDF and DO searches for a standard model Higgs boson in ppbar collisions at the Fermilab Tevatron, at sqrt{s}=1.96 TeV. With 3.0 fb-1 of data analyzed at CDF, and at DO, the 95% C.L. upper limits on Higgs boson production are a factor of 1.2, 1.0 and 1.3 higher than the SM cross section for a Higgs boson mass of m_{H}=$165, 170 and 175 GeV, respectively. We exclude at 95% C.L. a standard model Higgs boson of m_H=170 GeV. Based on simulation, the ratios of the corresponding median expected upper limit to the Standard Model cross section are 1.2, 1.4 and 1.7. Compared to …
I review recent searches for physics beyond the standard model from the CDF and D0 experiments at the Fermilab Tevatron collider, covering searches for fourth generation quarks, exotic resonances, universal extra dimensions, and dark matter particles.
The results of search for Supersymmetry performed at the Tevatron Collider by the CDF and D0 collaborations are summarized in this paper. No significant deviations with respect to the Standard Model expectations were observed and constraints were set on supersymmetric parameters.
We present the results from searches for fourth generation fermions performed using data samples collected by the CDF II and D0 Detectors at the Fermilab Tevatron ppbar collider. Many of these results represent the most stringent 95% C.L. limits on masses of new fermions to-date.
In this article results from supersymmetry searches at D0 and CDF are reported. Searches for third generation squarks, searches for gauginos, and searches for models with R-parity violation are described. As no signs of supersymmetry for these models are observed, the most stringent limits to date are presented.
