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Related papers: Rare top quark decays in extended models

200 papers

An overview of searches for top quark flavour changing neutral currents (FCNC) from the CDF, D0, ATLAS and CMS collaborations is presented. The FCNC interactions of top quarks are probed through the anomalous decays and production channels.…

High Energy Physics - Experiment · Physics 2019-08-15 Reza Goldouzian

We present a study to examine the sensitivity of a future $e^{-} e^{+}$ collider to the anomalous top flavour-changing neutral current (FCNC) to the gluon. To separate signal from background a multivariate analysis is performed on top-quark…

High Energy Physics - Experiment · Physics 2014-12-31 Hoda Hesari , Hamzeh Khanpour , Morteza Khatiri Yanehsari , Mojtaba Mohammadi Najafabadi

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

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

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 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

Decays of the top quark induced by flavor changing neutral currents (FCNC) are known to be extremely rare events within the Standard Model. This is so not only for the decay modes into gauge bosons, but most notably in the case of the Higgs…

High Energy Physics - Phenomenology · Physics 2010-03-26 Santi Bejar , Jaume Guasch , Joan Sola

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

We analyze the rare and flavor changing decay of the top quark into a charm quark and a gauge boson in the littlest Higgs model with T-parity (LHT). We calculate the one-loop level contributions from the T-parity odd mirror quarks and gauge…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hou Hong-Sheng

We show that supersymmetric $R$-parity breaking ($\not R_p$) interactions always result in Flavor Changing Neutral Current (FCNC) processes. Within a single coupling scheme, these processes can be avoided in either the charge $+2/3$ or the…

High Energy Physics - Phenomenology · Physics 2009-10-28 K. Agashe , M. Graesser

This letter documents a search for flavour-changing neutral currents (FCNCs), which are strongly suppressed in the Standard Model, in events with a photon and a top quark with the ATLAS detector. The analysis uses data collected in $pp$…

High Energy Physics - Experiment · Physics 2023-11-14 ATLAS Collaboration

Large top quark flavor changing through neutral currents is expected by many extensions of the standard model. Direct and indirect searches for flavor changing neutral currents (FCNC) in the top quark decays to an up type quark (up,charm)…

High Energy Physics - Phenomenology · Physics 2016-01-14 Hoda Hesari , Hamzeh Khanpour , Mojtaba Mohammadi Najafabadi

I would like to discuss $D^0-\bar{D}^0$ the mixing and rare D decays as manifestations of Flavor Changing Neutral Currents (FCNC) in the charm sector. I will first review the expectations in the Standard Model (SM) and then summarize some…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Pakvasa

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

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

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

Rare B meson decays mediated by flavour changing neutral current (FCNC) transition play interesting role to probe the flavour sector of the standard model (SM). Generally at the tree level, FCNC processes are not allowed in the SM but…

High Energy Physics - Phenomenology · Physics 2020-07-15 P. Nayek , S. Biswas , P. Maji , S. Sahoo

The Standard Model (SM) has no flavor-changing neutral current (FCNC) processes at the tree level. Therefore, processes featuring FCNC in new physics are tightly constrained by data. Typically, the lower bounds on the scale of new physics…

High Energy Physics - Phenomenology · Physics 2023-12-05 S. Kovalenko , A. S. de Jesus , A. R. Zerwekh , Y. M. Oviedo-Torres , F. S. Queiroz , T. B. de Melo , J. P. Neto , Y. S. Villamizar

We present the sensitivity to Flavor Changing Neutral Currents (FCNC) in interactions involving the top quark at future $e^+e^-$ and $\mu^+\mu^-$ machines. We consider the $Ztc$ vertex as well as four-fermion contact interactions involving…

High Energy Physics - Phenomenology · Physics 2026-01-22 Sagar Airen , Roberto Franceschini

We study the one-loop contribution of the effective flavor changing neutral couplings (FCNC) $tcZ$ to the charm quark electric dipole moment. Using the known limits on the top and charm quarks electric dipole moments, we place limits on…

High Energy Physics - Phenomenology · Physics 2010-04-21 M. Mohammadi Najafabadi , N. Tazik