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Related papers: FCNC top quark decays beyond the Standard Model

200 papers

We investigate the discovery potential of flavor changing neutral Higgs (FCNH) interactions in top quark decays at the LHC. A general two Higgs doublet model (2HDM) is adopted to study the top quark decay $t \to c \phi^0$, where $\phi^0$ is…

High Energy Physics - Phenomenology · Physics 2025-11-12 Chenyu Fang , Phillip Gutierrez , Chung Kao

In this work we study the flavor changing neutral current(FCNC) decays of the top quark, $t\to c\gamma$ and $t\to c g$. The Standard Model, predictions for the branching ratios of these decays are about $\sim 5\times 10^{-14}$, and $\sim…

High Energy Physics - Phenomenology · Physics 2009-01-16 T. M. Aliev , O. Cakir , K. O. Ozansoy

The two Higgs doublet model for the top (T2HDM) is a 2HDM in which the top quark receives a special status, which endows it with a naturally large mass, and also gives rise to unique FC charged and neutral scalar interactions. We calculate…

High Energy Physics - Phenomenology · Physics 2007-11-09 Itzhak Baum

We report a search for the flavor changing neutral current (FCNC) decay of the top quark \tZq ($q=u,c$) in \ppbar collisions at $\sqrt{s} = 1.96\tev$ using a data sample corresponding to an integrated luminosity of 1.9\invfb collected by…

High Energy Physics - Experiment · Physics 2010-05-12 CDF Collaboration , T. Aaltonen

We study a version of Two Higgs Doublet Models with non-standard flavor violation in the up quark sector. We find branching ratios for the rare top decays $t\to hc$ and $t\to hu$ that are within reach of current and future colliders, while…

High Energy Physics - Phenomenology · Physics 2019-07-17 Wolfgang Altmannshofer , Brian Maddock , Douglas Tuckler

The flavor changing neutral top quark decay t -> c X is computed, where X is a neutral standard model particle, in a extended model with a single extra dimension. The cases for the photon, X= \gamma$, and a Standard Model Higgs boson, X =…

High Energy Physics - Phenomenology · Physics 2009-11-11 G. A. Gonzalez-Sprinberg , R. Martinez , J. -Alexis Rodriguez

We survey the flavor-changing neutral couplings (FCNC) of the top quark predicted by some extensions of the Standard Model: THDM, SUSY, L-R symmetric, TC2, 331, and models with extra quarks. Since the expected sensitivity of the LHC and ILC…

High Energy Physics - Phenomenology · Physics 2009-11-11 F. Larios , R. Martinez , M. A. Perez

Flavour Changing Neutral Current (FCNC) processes are forbidden at tree level in the Standard Model and highly suppressed at higher orders. This makes FCNC one of the key processes to search for new physics since any small deviations from…

High Energy Physics - Experiment · Physics 2019-08-14 J. P. Araque

We study the FCNC top quark decays t -> c h in the framework of the MSSM, where h= h^0,H^0,A^0 is any of the supersymmetric neutral Higgs bosons. We include the leading set of SUSY-QCD and SUSY electroweak contributions. While the FCNC top…

High Energy Physics - Phenomenology · Physics 2011-02-11 Jaume Guasch , Joan Sola

Flavour-changing neutral current (FCNC) interactions between the Higgs boson and the top quark are subject to significant suppression within the Standard Model (SM). Consequently, these interactions can only attain an observable level…

High Energy Physics - Phenomenology · Physics 2025-03-24 Eda Alici

Since the top quark FCNC processes are extremely supressed in the Standard Model (SM) but could be greatly enhanced in some new physics models, they could serve as a smoking gun for new physics hunting at the LHC. In this brief review we…

High Energy Physics - Phenomenology · Physics 2010-10-27 Jin Min Yang

We investigate the potential of the HL-LHC for discovering new physics effects via the same-sign top pair signatures. We focus on the semi leptonic (electron and muon) decay of the top quarks and study the reach for a simplified model…

High Energy Physics - Phenomenology · Physics 2022-11-08 O. M. Ozsimsek , V. Ari , O. Cakir

In the so called two Higgs doublet model for the top-quark (T2HDM), first suggested by Das and Kao, the top quark receives a special status, which endows it with a naturally large mass, and also potentially gives rise to large flavor…

High Energy Physics - Phenomenology · Physics 2008-11-26 Itzhak Baum , Gad Eilam , Shaouly Bar-Shalom

The ATLAS experiment sensitivity to top quark Flavour Changing Neutral Current (FCNC) decays was studied at LHC using ttbar events. While one of the top quarks is expected to follow the dominant Standard Model decay t->bW, the other decays…

High Energy Physics - Experiment · Physics 2008-11-26 J. Carvalho , N. Castro , L. Chikovani , T. Djobava , J. Dodd , S. McGrath , A. Onofre , J. Parsons , F. Veloso

Searches for light charged Higgs bosons (H^\pm) in the decay of top quarks, t -> H^\pm b, are being carried out at the LHC and at the Tevatron. It is assumed that the dominant decay channels for such an H^\pm state are either H^\pm ->…

High Energy Physics - Phenomenology · Physics 2013-05-30 A. G. Akeroyd , J. Hernandez-Sanchez , S. Moretti

We determine the constraints on the anomalous top-quark coupling associated with the flavor-changing neutral current vertex $\bar t c \gamma $ from the limits on the $b$-quark rare decay $b\rightarrow s \gamma$ and non-standard top-quark…

High Energy Physics - Phenomenology · Physics 2016-08-24 T. Han , K. Whisnant , B. -L. Young , X. Zhang

A search for neutral Higgs bosons in the minimal supersymmetric extension of the Standard Model (MSSM) decaying to a pair of b quarks or a pair of tau leptons, using events recorded by the CMS experiment at the LHC in 2011 and 2012 at the…

High Energy Physics - Experiment · Physics 2019-08-13 Aruna Kumar Nayak

We examine the decays $t\rightarrow c\gamma$ and $c Z^0$ in the Standard Model with an extra scalar doublet and no discrete symmetry preventing tree-level flavour changing neutral currents. The Yukawa couplings of the new scalars are…

High Energy Physics - Phenomenology · Physics 2009-10-22 Michael Luke , Martin J. Savage

The observed flavor-changing neutral-current (FCNC) processes in the standard model (SM) arise from the loop diagrams involving the weak charged currents mediated by the $W$-gauge boson. Nevertheless, the top-quark FCNCs and lepton-flavor…

High Energy Physics - Phenomenology · Physics 2023-02-01 Chuan-Hung Chen , Cheng-Wei Chiang , Chun-Wei Su

The top quark decay process $\tcups$ is studied in the Standard Model and the Minimal Supersymmetric Standard Model with conserved and violated $R-$parity. In dealing with the heavy quarkonium, $\ups$, production, we take both color-singlet…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. T. Handoko , C. -F. Qiao