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Related papers: FCNC Top Quark Decays in Extra Dimensions

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A search for flavor-changing neutral currents in top-quark decays t to Zq is performed in events produced from the decay chain t t-bar to Zq + Wb, where both vector bosons decay leptonically, producing a final state with three leptons…

High Energy Physics - Experiment · Physics 2014-05-06 CMS Collaboration

We present an experimental and theoretical analysis of the ratio of branching ratios R=BR(H^+ -> tau^+ nu)/BR(H^+ -> t b-bar) of charged Higgs boson decays as a discriminant quantity between supersymmetric and non-supersymmetric models.

High Energy Physics - Phenomenology · Physics 2007-05-23 K. A. Assamagan , J. Guasch , S. Moretti , S. Penaranda

We study the branching ratio, CP-violating asymmetry, forward-backward asymmetry and the CP-violating asymmetry in the forward-backward asymmetry for the exclusive decay B--> K l^+ l^-$ in the two Higgs doublet model with tree level flavor…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. O. Iltan

Rare flavour changing neutral current (FCNC) decays of top, beauty and charm quarks can provide a powerful probe for as yet unobserved particles. Recent results on FCNC $b \to s$, $c \to u$ and $t$ transitions from the LHC experiments are…

High Energy Physics - Experiment · Physics 2014-08-25 Thomas Blake

The prospects of searching for the flavor changing neutral current effect in the decay of $t\to H c, H\to \tau\tau$ are investigated with the simulated $p-p$ collision data for the ATLAS detector at the LHC, where the Higgs mass is assumed…

High Energy Physics - Phenomenology · Physics 2016-06-29 Xin Chen , Li-Gang Xia

We consider the branching ratio for the process $t \to c \gamma$ in the context of the General Two Higgs Doublet Model type III. We find that taking into account reasonable values for the parameter $\tan \beta$ is possible to get values of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Rodolfo A. Diaz , R. Martinez , J-Alexis Rodriguez

A search for flavor-changing neutral current interactions of the top quark (t) and the Higgs boson (H) is presented. The search is based on a data sample corresponding to an integrated luminosity of 137 fb$^{-1}$ recorded by the CMS…

High Energy Physics - Experiment · Physics 2022-03-02 CMS Collaboration

A search for flavor-changing neutral current (FCNC) processes in associated production of a top quark and Higgs boson, with the Higgs boson decaying to a pair of b quarks, is presented. To experimentally probe the top-Higgs FCNC couplings,…

High Energy Physics - Experiment · Physics 2017-11-22 Predrag Cirkovic

Flavor-changing neutral current (FCNC) top-quark decays are highly suppressed due to the Glashow-Iliopoulos-Maiani mechanism in the standard model (SM). If $t\to q h, qV$ with $V=g,\gamma, Z$ are all induced via quantum loop levels, then we…

High Energy Physics - Phenomenology · Physics 2022-11-23 Chuan-Hung Chen , Takaaki Nomura

We perform a complete one-loop computation of the two-body flavour-changing top decays $t \rightarrow c h$ and $t \rightarrow c V$ ($V= \gamma, Z$), within the aligned two-Higgs-doublet model. We evaluate the impact of the model parameters…

High Energy Physics - Phenomenology · Physics 2015-06-02 Gauhar Abbas , Alejandro Celis , Xin-Qiang Li , Jie Lu , Antonio Pich

Recently we have presented an analysis of flavor changing neutral coupling mediated radiative top quark decays at next-to-leading order in QCD. In the present paper we provide the details of the calculation of QCD corrections to t-> q gamma…

High Energy Physics - Phenomenology · Physics 2010-11-11 Jure Drobnak , Svjetlana Fajfer , Jernej F. Kamenik

The one-loop level mediated $t-> c \gamma$ decay is analyzed in the framework of 331 models, which induce three-level flavor-changing neutral currents mediated by an extra neutral gauge boson, Z', and a neutral scalar boson, \phi. These…

High Energy Physics - Phenomenology · Physics 2013-07-15 I. Cortés-Maldonado , G. Hernández-Tomé , G. Tavares-Velasco

We compute the contributions to rare top decays $t\rightarrow cZ$ and $t\rightarrow ch_1$ from the scalar sector in the 2HDM type III with CP violation, where $h_1$ is the Standard Model Higgs boson. The branching ratio for $BR(t\rightarrow…

High Energy Physics - Phenomenology · Physics 2018-08-29 Ricardo Gaitán , Roberto Martinez , Jose Halim Montes de Oca , Estela A. Garcés

ATLAS results are presented on a search for flavor-changing neutral currents (FCNC) in top quark decays at the LHC. Events are searched for where a pair of top quarks is produced and one decays through the Standard Model $t \rightarrow Wb$…

High Energy Physics - Experiment · Physics 2015-06-03 Arely Cortes-Gonzalez

We discuss the production and the decay of top quark through flavor-changing neutral current (FCNC) interaction at future linear colliders. We first discuss the theoretical predictions of top quark FCNC decays into $qH$ and $qZ$ within a…

High Energy Physics - Phenomenology · Physics 2024-10-01 Adil Jueid , Shinya Kanemura

Analyticity and unitarity constrain certain classe of new physics models by linking flavor-conserving and flavor-violating four-fermion interactions. In this work, we explore how these theoretical relations impact flavor-violating rare top…

High Energy Physics - Phenomenology · Physics 2025-09-09 Wolfgang Altmannshofer , Zev Balme , Christopher M. Donohue , Stefania Gori , Siddharth Vignesh Mukundhan

The LHC will have unprecedented sensitivity to flavor-changing neutral current (FCNC) top quark decays, whose observation would be a clear sign of physics beyond the standard model. Although many details of top flavor violation are model…

High Energy Physics - Phenomenology · Physics 2009-01-22 Patrick J. Fox , Zoltan Ligeti , Michele Papucci , Gilad Perez , Matthew D. Schwartz

Kaluza-Klein fields characterizing, from a four-dimensional viewpoint, the presence of compact universal extra dimensions would alter low-energy observables through effects determined by some compactification scale, $R^{-1}$, since the…

High Energy Physics - Phenomenology · Physics 2020-03-13 Carlos M. Farrera , Alejandro Granados-González , Héctor Novales-Sánchez , J. Jesús Toscano

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

A search for flavour changing neutral current (FCNC) processes in top-quark decays by the ATLAS Collaboration is presented. Data collected from pp collisions at the LHC at a centre-of-mass energy of sqrt(s) = 7 TeV during 2011,…

High Energy Physics - Experiment · Physics 2013-06-11 ATLAS Collaboration