Related papers: Possible Solution to $R_b$ -- $R_c$ Problem

A search for flavour-changing neutral current decays of a top quark to an up-type quark ($q=u, c$) and the Standard Model Higgs boson, where the Higgs boson decays to $b\bar{b}$, is presented. The analysis searches for top quark pair events…

Extending the Higgs sector by an additional $SU(2)_L$ doublet Higgs boson implies the existence of a charged Higgs boson $H^+$. The LHC experiments search for such particle focusing on it decays into leptonic and quark decay final states,…

In this article, we demonstrate that the unexpected peak at around $95 \, {\rm GeV}$ as seen recently by CMS in the di-photon final state can be explained within the type-I~two-Higgs-doublet model by means of a moderately-to-strongly…

Dark Matter (DM), arising from an Inert Higgs Doublet, may either be light, below the $W$ mass, or heavy, above about 525 GeV. While the light region may soon be excluded, the heavy region is known to be very difficult to probe with either…

We present a search for charged Higgs bosons in top quark decays. We analyze the \eplus, \muplus, $ee$, $e\mu$, $\mu\mu$, \etau and \mutau final states from top quark pair production events, using data from about 1${\text{fb}}^{-1}$ of…

We present an analysis with improved sensitivity to the light charged Higgs ($m_{H^+} < m_t-m_b$) searches in the top quark decays $t \to b H^+ \to b (\tau^+\nu_\tau) + ~{\rm c.c.}$ in the $t\bar{t}$ and single $t/\bar{t}$ production…

In this presentation I will concentrate on top quark physics, the W-boson mass and the possibility of discovering a light Higgs boson via associated production at the Fermilab Tevatron.

We study the phenomenology of the charged Higgs boson in the "flipped" two Higgs doublet model, in which one doublet gives mass to up-type quarks and charged leptons and the other gives mass to down-type quarks. We present the charged Higgs…

Recent measurements of the top quark charge asymmetry at Tevatron disfavor the existence of flavor universal axigluons and colorons at 2 sigmas. In this letter we explore the possibility to reconcile the data with these models and use the…

Recent precise measurement of the electron anomalous magnetic moment (AMM) adds to the longstanding tension of the muon AMM and together strongly point towards physics beyond the Standard Model (BSM). In this work, we propose a solution to…

We present a measurement of the electric charge of the top quark using $\ppbar$ collisions corresponding to an integrated luminosity of 2.7~fb$^{-1}$ at the CDF II detector. We reconstruct $\ttbar$ events in the lepton+jets final state and…

Constraints on the two Higgs doublet model are presented, assuming a top mass of 174 $\pm$ 17 GeV. We concentrate primarily on the ``type II'' model, where up--type quarks receive their mass from one Higgs doublet, and down--type quarks…

Several models predict the existence of heavy colored resonances decaying to top quarks in the TeV energy range that might be discovered at the LHC. In some of those models, moreover, a sizable charge asymmetry of top versus antitop quarks…

In this presentation I will primarily focus on top quark physics but I will include a discussion of the W-boson mass and the possibility of discovering a light Higgs boson via associated production at the Tevatron.

The quadratic divergences of the Higgs mass may be cancelled either accidentally or by the exchange of some new particles. Alternatively its impact on naturalness may be weakened by raising the Higgs mass, which requires changing the…

We report on a search for charged massive resonances decaying to top ($t$) and bottom ($b$) quarks in the full data set of proton-antiproton collisions at center-of-mass energy of $\sqrt{s} = 1.96$ TeV collected by the CDF~II detector at…

In the standard model, for the t --> W b decay mode, the relative phase is 0-degrees between the dominant A(0,-1/2) and A(-1, -1/2) helicity amplitudes. However, in the case of an additional large t_R --> b_L chiral weak-transition moment,…

In this thesis, the first determination of the electric charge of the top quark is presented using 370pb-1 of data recorded by the D0 detector at the Fermilab Tevatron accelerator. ttbar events are selected with one isolated electron or…

We propose a new method for detecting a charged (pseudo-)scalar at colliders, based upon the observation that its Yukawa coupling to charm and bottom quarks can be large due to a significant mixing of the top and charm quarks. After…

We present the masses of singly ($B$, $B_s$, $\Lambda_b$, $\Sigma_b$, etc.), doubly ($B_c$, $\eta_b$, $\Upsilon$, $\Xi_{bc}$, $\Xi_{bb}$, etc.), and triply ($\Omega_{bcc}$, $\Omega_{bbc}$, $\Omega_{bbb}$, etc.) heavy hadrons arising from…