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Related papers: Unparticle effects on top quark rare decays

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We have used the Collider Detector at Fermilab (CDF II) to search for the flavor-changing neutral-current (FCNC) top quark decay ${t\goes Zc}$ using a technique employing ratios of $W$ and $Z$ production, measured in \ppbar data…

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

A calculation of the one-loop contribution to the rare three-body flavor changing neutral current top quark decay $t\to c\gamma\gamma$ is presented in the framework of models with one or more scalar leptoquark $SU(2)$ doublets with…

High Energy Physics - Phenomenology · Physics 2023-05-24 A. Bolaños-Carrera , R. Sánchez-Vélez , G. Tavares-Velasco

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 rare top decay t-> c l+l-, which involves flavor violation, is studied as a possible probe of new physics. This decay is analyzed with the simplest Standard Model extensions with additional gauge symmetry formalism. The considered…

High Energy Physics - Phenomenology · Physics 2015-06-04 J. L. Diaz-Cruz , A. Diaz-Furlong , R. Gaitan-Lozano , J. H. Montes de Oca Y

The latest searches for flavor changing neutral currents (FCNCs) and measurements of properties in top quark events at the CMS and ATLAS experiments are presented. The vast amounts of proton-proton collision data recorded during the CERN…

High Energy Physics - Experiment · Physics 2023-06-14 Gerrit Van Onsem

The rare top quark decays mediated by a new neutral massive gauge boson that is predicted in models with extended gauge symmetries are studied. We focus on the processes $t\to cV, uV$ induced at the one loop level, where $V =\gamma, g$, by…

High Energy Physics - Phenomenology · Physics 2020-05-06 J. I. Aranda , D. Espinosa-Gomez , J. Montano , F. Ramirez-Zavaleta , E. S. Tututi

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

The sensitivity of the ATLAS experiment to the top-quark rare decay via flavor-changing neutral currents $t \rightarrow Zq$ ($q$ represents $c$ and $u$ quarks) has been studied at $\sqrt{s}$=14 TeV in two decay modes: 1.The pure leptonic…

High Energy Physics - Experiment · Physics 2007-05-23 Leila Chikovani , Tamar Djobava

The top quark flavor changing neutral current processes are extremely suppressed within the Standard Model. Nevertheless, they could be enhanced in a new physics model beyond the Standard Model. Investigating the top quark's flavor changing…

High Energy Physics - Phenomenology · Physics 2024-08-12 Eda Alici

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

If the LHC should fail to observe direct signals for new physics, it may become necessary to look for new physics effects in rare events such as flavour-changing decays of the top quark, which, in the Standard Model, are predicted to be too…

High Energy Physics - Phenomenology · Physics 2016-08-09 Debjyoti Bardhan , Gautam Bhattacharyya , Diptimoy Ghosh , Monalisa Patra , Sreerup Raychaudhuri

Models beyond the Standard Model with extra scalars have been highly motivated by the recent discovery of a Higgs boson. The Two Higgs Doublet Model Type III considers the most general case for the scalar potential, allowing mixing between…

High Energy Physics - Phenomenology · Physics 2016-12-07 Ricardo Gaitán , Estela A. Garcés , Roberto Martinez , Jose Halim Montes de Oca

Observation of top quark flavor changing neutral process $t\to c +\gamma$ at the LHC would be the signal of physics beyond the Standard Model. If anomalous $t\to c\gamma$ coupling exists, it will affect the precisely measured…

High Energy Physics - Phenomenology · Physics 2011-02-01 Xing-Bo Yuan , Yang Hao , Ya-Dong Yang

A study of single top quark production via flavor changing neutral current interactions at $tq\gamma$ vertices is performed at future circular hadron electron collider. The signal cross sections for the processes $e^{-}p\to e^{-}W^{\pm}q+X$…

High Energy Physics - Phenomenology · Physics 2017-07-28 H. Denizli , A. Senol , A. Yilmaz , I. T. Cakir , H. Karadeniz , O. Cakir

We have investigated the flavor changing top quark physics on the dimension-six anomalous $tq\gamma$ ($q=u,c$) couplings through the process $pp\to p\gamma \gamma p\to p t\bar{q}p$ at the LHC by considering different forward detector…

High Energy Physics - Phenomenology · Physics 2015-06-17 S. C. İnan

The results of a search for flavor changing neutral currents in top quark decays t to Zq in events with a topology compatible with the decay chain t t-bar to Wb + Zq to ell nu b + ell ell q are presented. The search is performed with a data…

High Energy Physics - Experiment · Physics 2013-03-21 CMS Collaboration

Flavor-changing neutral currents (FCNC) are studied on the basis of a ``democratic seesa'' mass matrix model, which yields a singular enhancement of the top-quark mass m_t and can give reasonable quark masses and CKM matrix elements. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yoshio Koide

We calculate flavor-changing neutral current (FCNC) processes with top-quark production via anomalous couplings at LHC energies. We report on progress on the FCNC processes gu -> tZ, gu -> t gamma and gu -> tg. We go beyond leading order…

High Energy Physics - Phenomenology · Physics 2013-10-02 Nikolaos Kidonakis , Elwin Martin

This paper investigates the effects of parameters in the Bestest Little Higgs Model (BLHM) on rare flavor-changing decays of the top quark. As a result, flavor-changing phenomena are introduced in the BLHM for the first time. In this study,…

High Energy Physics - Phenomenology · Physics 2023-06-30 T. Cisneros-Pérez , M. A. Hernández-Ruíz , A. Gutiérrez-Rodríguez , E. Cruz-Albaro

Our main aim in this paper is to present detailed studies to probe the top quark flavor changing neutral current (FCNC) interactions at $tqg$, $tq\gamma$, $tqH$ and $tqZ (\sigma^{\mu \nu}, \gamma_{\mu})$ vertices in the triple-top signal $p…

High Energy Physics - Phenomenology · Physics 2020-08-18 Hamzeh Khanpour