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I present the latest results from the CDF and D0 collaborations on top quark production (single top and top quark pair production) at the Tevatron proton-antiproton collider at sqrt(s) =1.96 TeV, measurements of the top quark decay…

High Energy Physics - Experiment · Physics 2014-11-17 Christophe Clement

A search for new particles decaying to top quark-antiquark pairs is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV. The data set recorded with the CMS detector between 2016 and 2018 is used, corresponding…

High Energy Physics - Experiment · Physics 2026-03-25 CMS Collaboration

Concentrating on the impact of the very recent top quark discovery, we perform a combined analysis of two strongest constraints on the 2 Higgs doublet model, one coming from the recent measurement by CLEO on the inclusive branching ratio of…

High Energy Physics - Phenomenology · Physics 2015-06-25 Gye T. Park

The polarization of the $W$ boson in $t \to W b$ decay is unambiguously predicted by the Standard Model of weak interactions and is a powerful test of our understanding of the $tbW$ vertex. The subsequent $W \to l \nu$ decay serves as a…

High Energy Physics - Experiment · Physics 2012-08-27 CDF Collaboration

The heavy fourth generation of quarks that have sufficiently small mixing with the three known SM families form hadrons. In the present work, we calculate the masses and decay constants of mesons containing either both quarks from the…

High Energy Physics - Phenomenology · Physics 2015-03-19 V. Bashiry , K. Azizi , S. Sultansoy

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…

High Energy Physics - Experiment · Physics 2010-11-11 N. van Remortel

We study the effect of a potential fourth quark generation on the upper and lower Higgs boson mass bounds. This investigation is based on the numerical evaluation of a chirally invariant lattice Higgs-Yukawa model emulating the same…

High Energy Physics - Lattice · Physics 2011-02-03 P. Gerhold , K. Jansen , J. Kallarackal

Attention is drawn to the several 2-3 $\sigma$ "anomalies" in B, $B_s$ mixings and decays involving CP-observables. Perhaps the most interesting theoretical scenario that could cause such effects is based on warped extra-dimensional models…

High Energy Physics - Phenomenology · Physics 2009-07-14 Amarjit Soni

A search is presented for the pair production of new heavy resonances, each decaying into a top quark (t) or antiquark and a gluon (g). The analysis uses data recorded with the CMS detector from proton-proton collisions at a center-of-mass…

High Energy Physics - Experiment · Physics 2025-04-01 CMS Collaboration

Searches are presented for heavy gauge bosons decaying into a top and a bottom quark in data collected by the CMS experiment at sqrt(s) = 13 TeV that correspond to an integrated luminosity of 2.2 and 2.6 inverse femtobarns in the leptonic…

High Energy Physics - Experiment · Physics 2017-08-14 CMS Collaboration

A search for singly produced vector-like $Q$ quarks, where $Q$ can be either a $T$ quark with charge $+2/3$ or a $Y$ quark with charge $-4/3$, is performed in proton-proton collisions recorded with the ATLAS detector at the LHC. The dataset…

High Energy Physics - Experiment · Physics 2016-09-15 ATLAS Collaboration

We investigate the impact of the fourth generation quarks on production and decays of the charged Higgs boson at CERN Large Hadron Collider (LHC) with triple $b$-tagging. The signal is the process $gg\to \bar{u_4}u_4$, followed by…

High Energy Physics - Phenomenology · Physics 2008-07-08 R. Ciftci , A. K. Ciftci , S. Sultansoy

Using the theoretical and experimental results on $B \to X_s \gamma$, a four-generation SM is analyzed to constrain the combination of the $4\times 4$ Cabibbo-Kobayashi-Maskawa factor $V_{t^\prime s}^* V_{t^\prime b}$ as a function of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. Solmaz

Current mass limits for fourth generation sequential neutrinos come from dark matter experiments assuming $\rho_{DM}=0.2-0.8$ g/ cm$^3$. We show that the latest results from the CDMS II experiment exclude Dirac neutrinos with masses below…

High Energy Physics - Experiment · Physics 2007-05-23 Gray Rybka , Peter Fisher

A search is presented for the pair production of heavy vector-like $B$ quarks, primarily targeting $B$ quark decays into a $W$ boson and a top quark. The search is based on $36.1$ $fb^{-1}$ of $pp$ collisions at $\sqrt{s}$ = 13 TeV recorded…

High Energy Physics - Experiment · Physics 2018-08-14 ATLAS Collaboration

A global analysis is performed using the latest data from LEP and SLC. Constraints on the electroweak universal parameters ($S,T,U$) and on the masses of the top quark and Higgs boson within the Standard Model (SM) are investigated. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Seiji Matsumoto

We estimate the CP asymmetry A_{CP}(q^2) in the decays B --> X_s mu+ mu- and B --> X_d mu+ mu- in the standard model (SM) with an additional fourth generation. We use a parametrization that allows us to explore the complete parameter space…

High Energy Physics - Phenomenology · Physics 2010-02-08 Ashutosh Kumar Alok , Amol Dighe , Shamayita Ray

If the fourth generation fermions exist, the new quarks could influence the branching ratio of the rare $B\to K^{*}\nu\bar{\nu}$ decay. Two possible solutions of the fourth generation CKM factor $(V^{*}_{\acute{t}s}V_{\acute{t}b})^(\pm)$…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thabit Barakat

We discuss the possible existence of the fully-heavy tetraquarks. We calculate the ground-state energy of the $bb \bar b \bar b$ bound state, where $b$ stands for the bottom quark, in a nonrelativistic effective field theory framework with…

High Energy Physics - Phenomenology · Physics 2018-07-17 Muhammad Naeem Anwar , Jacopo Ferretti , Feng-Kun Guo , Elena Santopinto , Bing-Song Zou

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…

High Energy Physics - Experiment · Physics 2007-09-17 Susana Cabrera