Phys. Rev. D 91, 012002 (2015) Differential cross sections for the production of $Z$ bosons or off-shell
photons $\gamma^*$ in association with jets are measured in proton-antiproton
collisions at ...center-of-mass energy $\sqrt{s}=1.96$ TeV using the full data set
collected with the Collider Detector at Fermilab in Tevatron Run II, and
corresponding to 9.6 fb$^{-1}$ of integrated luminosity. Results include first
measurements at CDF of differential cross sections in events with a
$Z/\gamma^*$ boson and three or more jets, the inclusive cross section for
production of $Z/\gamma^*$ and four or more jets, and cross sections as
functions of various angular observables in lower jet-multiplicity final
states. Measured cross sections are compared to several theoretical
predictions.
This paper presents a study of the production of a single \(W\) boson in association with one or more jets in proton-antiproton collisions at \(\sqrt{s}=1.96\) TeV, using the entire data set ...collected in 2001-2011 by the Collider Detector at Fermilab at the Tevatron, which corresponds to an integrated luminosity of \(9.0\) fb\(^{-1}\). The \(W\) boson is identified through its leptonic decays into electron and muon. The production cross sections are measured for each leptonic decay mode and combined after testing that the ratio of the \(W(\rightarrow \mu\nu)+\)jets cross section to the \(W(\rightarrow e\nu)+\)jets cross section agrees with the hypothesis of \(e\)-\(\mu\) lepton universality. The combination of measured cross sections, differential in the inclusive jet multiplicity (\(W+\geqslant N\) jets with \(N=1,\,2,\,3, \textrm{or }4\)) and in the transverse energy of the leading jet, are compared with theoretical predictions.
Results of a study of the substructure of the highest transverse momentum (pT) jets observed by the CDF collaboration are presented. Events containing at least one jet with pT > 400 GeV/c in a sample ...corresponding to an integrated luminosity of 5.95 inverse fb, collected in 1.96 TeV proton-antiproton collisions at the Fermilab Tevatron collider, are selected. A study of the jet mass, angularity, and planar-flow distributions is presented, and the measurements are compared with predictions of perturbative quantum chromodynamics. A search for boosted top-quark production is also described, leading to a 95% confidence level upper limit of 38 fb on the production cross section of top quarks with pT > 400 GeV/c.
We present a measurement of the ZZ boson-pair production cross section in 1.96 TeV center-of-mass energy ppbar collisions. We reconstruct final states incorporating four charged leptons or two ...charged leptons and two neutrinos from the full data set collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.7 fb-1 of integrated luminosity. Combining the results obtained from each final state, we measure a cross section of 1.04(+0.32)(-0.25) pb, in good agreement with the standard model prediction at next-to-leading order in the strong-interaction coupling.
We present an analysis of top-antitop quark production and decay into a tau lepton, tau neutrino, and bottom quark using data from \(9 {\rm fb}^{-1}\) of integrated luminosity at the Collider ...Detector at Fermilab. Dilepton events, where one lepton is an energetic electron or muon and the other a hadronically-decaying tau lepton, originating from proton-antiproton collisions at \(\sqrt{s} = 1.96 TeV\) are used. A top-antitop quark production cross section of \(8.1 \pm 2.1 {\rm pb}\) is measured, assuming standard-model top-quark decays. By separately identifying for the first time the single-tau and the ditau components, we measure the branching fraction of the top quark into tau lepton, tau neutrino, and bottom quark to be \((9.6 \pm 2.8) %\). The branching fraction of top-quark decays into a charged Higgs boson and a bottom quark, which would imply violation of lepton universality, is limited to be less than \(5.9%\) at \(95%\) confidence level.
We measure the inclusive forward-backward asymmetry of the charged-lepton pseudorapidities from top-quark pairs produced in proton-antiproton collisions, and decaying to final states that contain two ...charged leptons (electrons or muons), using data collected with the Collider Detector at Fermilab. With an integrated luminosity of 9.1 \(\rm{fb}^{-1}\), the leptonic forward-backward asymmetry, \(A_{\text{FB}}^{\ell}\), is measured to be \(0.072 \pm 0.060\) and the leptonic pair forward-backward asymmetry, \(A_{\text{FB}}^{\ell\ell}\), is measured to be \(0.076 \pm 0.082\), compared with the standard model predictions of \(A_{\text{FB}}^{\ell} = 0.038 \pm 0.003\) and \(A_{\text{FB}}^{\ell\ell} = 0.048 \pm 0.004\), respectively. Additionally, we combine the \(A_{\text{FB}}^{\ell}\) result with a previous determination from a final state with a single lepton and hadronic jets and obtain \(A_{\text{FB}}^{\ell} = 0.090^{+0.028}_{-0.026}\).
Phys. Rev. Lett. 112, 221801 (2014) We present a measurement of the ratio of the top-quark branching fractions
$R=\mathcal{B}(t\rightarrow Wb)/\mathcal{B}(t\rightarrow $ $q$ represents
quarks of ...flavors $b$, $s$, or $d$, in the final state, in events with two
charged leptons, missing transverse energy and at least two jets. The
measurement uses $\sqrt{s}$ = 1.96 TeV proton--antiproton collision data
corresponding to an integrated luminosity of 8.7 fb$^{-1}$ and collected with
the Collider Detector at Fermilab during Run II of the Tevatron. We measure
$R=0.87 \pm 0.07$ (stat+syst), and extract the magnitude of the
Cabibbo-Kobayashi-Maskawa matrix element, $\left|V_{tb}\right| = 0.93 \pm 0.04$
(stat+syst) assuming three generations of quarks. Under these assumptions, a
lower limit of $|V_{tb}|>0.85$ at 95% credibility level is set.
Phys. Rev. D 89, 072014 (2014) We report on mass and lifetime measurements of several ground state charmed
and bottom baryons, using a data sample corresponding to 9.6 $\textrm{fb}^{-1}$
from $p\bar ...p$ collisions at $\sqrt{s}=1.96$ TeV, and recorded with the
Collider Detector at Fermilab. Baryon candidates are reconstructed from data
collected with an online event selection designed for the collection of
long-lifetime heavy-flavor decay products and a second event selection designed
to collect $J/\psi \rightarrow \mu^+ \, \mu^-$ candidates. First evidence for
the process $\Omega_b^- \rightarrow \Omega_c^0 \, \pi^-$ is presented with a
significance of $3.3\sigma$. We measure the following baryon masses:
\begin{eqnarray}
M(\Xi_c^{0}) = 2470.85\pm0.24(stat)\pm0.55(syst) \, MeV/c^2, \nonumber
M(\Xi_c^{+}) = 2468.00\pm0.18(stat)\pm0.51(syst) \, MeV/c^2, \nonumber \\
M(\Lambda_b) = 5620.15\pm0.31(stat)\pm0.47(syst) \, MeV/c^2, \nonumber \\
M(\Xi_b^-) = 5793.4\pm1.8(stat)\pm0.7(syst) \, MeV/c^2, \nonumber \\ M(\Xi_b^0)
= 5788.7\pm4.3(stat)\pm1.4(syst) \, MeV/c^2, \, and \nonumber \\ M(\Omega_b^-)
= 6047.5\pm3.8(stat)\pm0.6(syst) \, MeV/c^2. \nonumber \end{eqnarray} The
isospin splitting of the $\Xi_b^{-,0}$ states is found to be
$M(\Xi_b^-)-M(\Xi_b^0)=4.7\pm4.7(stat)\pm0.7(syst)$ MeV/$c^2$. The isospin
splitting of the $\Xi_c^{0,+}$ states is found to be $M(\Xi_c^0)-M(\Xi_c^+)$ =
$2.85\pm0.30(stat)\pm0.04(syst)$ MeV/$c^2$. The following lifetime measurements
are made: \begin{eqnarray} \tau(\Lambda_b) = 1.565\pm0.035(stat)\pm0.020(syst)
\, ps, \nonumber \\ \tau(\Xi_b^-) = 1.32\pm0.14(stat)\pm0.02(syst) \, ps,
\nonumber \\ \tau(\Omega_b^-) = 1.66^{+0.53}_{-0.40}(stat)\pm0.02(syst) \, ps.
\nonumber \end{eqnarray}
Phys. Rev. Lett. 112, 231805 (2014) The first search for single top quark production from the exchange of an
$s$-channel virtual $W$ boson using events with an imbalance in the total
transverse ...momentum, $b$-tagged jets, and no identified leptons is presented.
The full data set collected by the Collider Detector at Fermilab, corresponding
to an integrated luminosity of 9.45 fb$^{-1}$ from Fermilab Tevatron
proton-antiproton collisions at a center of mass energy of 1.96 TeV, is used.
Assuming the electroweak production of top quarks of mass 172.5 GeV/$c^2$ in
the $s$-channel, a cross section of $1.12_{-0.57}^{+0.61}$ (stat+syst) pb, with
a significance of 1.9 standard deviations, is measured. This measurement is
combined with a previous result obtained from events with an imbalance in total
transverse momentum, $b$-tagged jets, and exactly one identified lepton,
yielding a cross section of $1.36_{-0.32}^{+0.37}$ (stat+syst) pb, with a
significance of 4.2 standard deviations.
Drell-Yan lepton pairs are produced in the process $p\bar{p} \rightarrow
\mu^+\mu^- + X$ through an intermediate $\gamma^*/Z$ boson. The
forward-backward asymmetry in the polar-angle distribution of ...the $\mu^-$ as a
function of the invariant mass of the $\mu^+\mu^-$ pair is used to obtain the
effective leptonic determination $\sin^2 \theta^{lept}_{eff}$ of the
electroweak-mixing parameter $\sin^2 \theta_W$, from which the value of $\sin^2
\theta_W$ is derived assuming the standard model. The measurement sample,
recorded by the Collider Detector at Fermilab (CDF), corresponds to 9.2 fb-1 of
integrated luminosity from $p\bar{p}$ collisions at a center-of-momentum energy
of 1.96 TeV, and is the full CDF Run II data set. The value of $\sin^2
\theta^{lept}_{eff}$ is found to be 0.2315 +- 0.0010, where statistical and
systematic uncertainties are combined in quadrature. When interpreted within
the context of the standard model using the on-shell renormalization scheme,
where $\sin^2 \theta_W = 1 - M_W^2/M_Z^2$, the measurement yields $\sin^2
\theta_W$ = 0.2233 +- 0.0009, or equivalently a W-boson mass of 80.365 +- 0.047
GeV/c^2. The value of the W-boson mass is in agreement with previous
determinations in electron-positron collisions and at the Tevatron collider.
