English
Related papers

Related papers: FCNC top quark decays beyond the Standard Model

200 papers

The result of a search for flavor changing neutral currents (FCNC) through single top quark production in association with a photon is presented. The study is based on proton-proton collisions at a center-of-mass energy of 8 TeV using data…

High Energy Physics - Experiment · Physics 2016-04-14 CMS Collaboration

We suggest a simplified model that simultaneously addresses the dark-matter problem and give rise to top quark flavor changing neutral current (FCNC) interactions at the one-loop order. The model consists of two extra $SU(2)_L$ gauge…

High Energy Physics - Phenomenology · Physics 2024-02-14 Adil Jueid , Shinya Kanemura

Among other roles the LHC will play a role of the top "factory" and it will give us unique possibility to study new physics signatures in different ways. Many scenarios of new physics allow top quark FCNC decays. Using most general model…

High Energy Physics - Phenomenology · Physics 2009-11-05 Jure Drobnak , Svjetlana Fajfer , Jernej F. Kamenik

Over a decade since the discovery of the top quark we are still trying to unravel mysteries of the heaviest observed particle and learn more about its nature. The continuously accumulating statistics of CDF and Dzero data provide the means…

High Energy Physics - Experiment · Physics 2019-08-14 Andrew G. Ivanov

The flavor changing neutral current (FCNC) transitions t --> q'H and t --> q'V_i (V_i=\gamma, g, Z) are studied in the context of the effective Lagrangian approach. We focus on the scenario in which these decays are predominantly induced by…

High Energy Physics - Phenomenology · Physics 2014-11-17 Adriana Cordero-Cid , M. A. Perez , G. Tavares-Velasco , J. J. Toscano

We analyse the constraints and some of the phenomenological implications of a class of two Higgs doublet models where there are flavour-changing neutral currents (FCNC) at tree level but the potentially dangerous FCNC couplings are…

High Energy Physics - Phenomenology · Physics 2015-06-18 F. J. Botella , G. C. Branco , Adrian Carmona , M. Nebot , Leonardo Pedro , M. N. Rebelo

In a general two Higgs doublet model, we study flavor changing neutral Higgs (FCNH) decays into leptons at hadron colliders, $pp \to \phi^0 \to \tau^\mp\mu^\pm +X$, where $\phi^0$ could be a CP-even scalar ($h^0$, $H^0$) or a CP-odd…

High Energy Physics - Phenomenology · Physics 2019-07-24 Wei-Shu Hou , Rishabh Jain , Chung Kao , Masaya Kohda , Brent McCoy , Amarjit Soni

We discuss the formalism of two Higgs doublet model type III with CP violation from CP-even CP-odd mixing in the neutral Higgs bosons. The flavor changing interactions among neutral Higgs bosons and fermions are presented at tree level in…

High Energy Physics - Phenomenology · Physics 2015-06-18 R. Gaitán , R. Martinez , J. H. Montes de Oca Y. , S. Rodriguez Romo

In the present work we consider including the Flavor Changing Neutral Currents (FCNCs) in Left-Right Symmetric model. Within this model a simulation calculation are made of the decay width of Z' LR boson, the production cross section of the…

High Energy Physics - Phenomenology · Physics 2014-10-06 H. M. M. Mansour , N. Bakheet

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

The investigation of flavour-changing neutral current transitions(FCNC) involving the top quark are only possible with new theoretical frameworks that extend the Standard Model(SM), given that these transitions are almost entirely…

High Energy Physics - Phenomenology · Physics 2024-12-13 Eda Alici

We discuss an extended standard model electroweak sector which contains a stable scalar dark matter particle, the D boson. To search for the D boson at the LHC we exploit the flavor-changing neutral current (FCNC) top quark decay, t->c D D,…

High Energy Physics - Phenomenology · Physics 2015-03-17 Tong Li , Qaisar Shafi

Scalar singlets under the Standard Model gauge group appear naturally in many well-motivated New Physics scenarios, such as the composite Higgs models. Unlike the Higgs boson in the Standard Model, they can induce large flavour-changing…

High Energy Physics - Phenomenology · Physics 2025-01-14 Biao-Feng Hou , Xin-Qiang Li , Ya-Dong Yang , Xing-Bo Yuan , Ming-Wang Zhang

The direct searches for Beyond Standard Model (BSM) particles have been constraining their mass scale to the extent where it is now becoming consensual that such particles are likely to be above the energy reach of the LHC. Meanwhile, the…

High Energy Physics - Experiment · Physics 2022-09-21 A. Hicheur

The Tevatron experiments CDF and D0 investigated the top quark decay in search of deviations from the Standard Model. Rare processes expected in the Standard Model as well as decays including hypothetical particles of models beyond the…

High Energy Physics - Experiment · Physics 2022-03-02 Daniel Wicke

We present a search for flavor changing neutral currents (FCNC) in decays of top quarks. The analysis is based on a search for $t\bar{t}\rightarrow\ell'\nu\ell\bar{\ell}$+jets ($\ell, \ell' = e,\mu$) final states using 4.1 {\rm fb}$^{-1}$…

High Energy Physics - Experiment · Physics 2019-08-14 C. L. McGivern

We present a comprehensive, model-independent analysis of rare flavour-changing neutral current (FCNC) interactions of the top quark within an effective field theory framework. Beginning with a general parametrisation of top-FCNC couplings,…

High Energy Physics - Phenomenology · Physics 2026-02-12 Subhajit Kala , Soumitra Nandi

One of the most interesting puzzles in particle physics today is that new physics is expected at the TeV energy scale to solve the hierarchy problem, and stabilise the Higgs mass, but so far no unambiguous signal of new physics has been…

High Energy Physics - Phenomenology · Physics 2017-01-04 Thomas Blake , Gaia Lanfranchi , David M. Straub

These proceedings present a search for flavour-changing neutral-current (FCNC) interaction involving the top quark, Higgs boson and either the up or the charm quark, using 140 fb$^{-1}$ of 13 TeV proton--proton collision data from the ATLAS…

High Energy Physics - Experiment · Physics 2026-02-04 Shayma Wahdan , On behalf of the ATLAS collaboration

CP4 3HDM is a peculiar three-Higgs-doublet model in which a single symmetry leads to tight constraints on the scalar and Yukawa sectors. In this models, tree-level flavor-changing neutral couplings are unavoidable; however, as previously…

High Energy Physics - Phenomenology · Physics 2025-11-26 Duanyang Zhao , Igor P. Ivanov