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Related papers: Flavor Changing Neutral Currents involving Heavy Q…

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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 discuss the Flavor-Changing Neutral Current (FCNC) decays of the top quark t -> c Vi Vj (Vi=gamma, Z, g) in the framework of the Standard Model (SM) and in a two-higgs doublet model (2HDM) with tree-level FCNC couplings. While in the SM…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. L. Diaz-Cruz , M. A. Perez , G. Tavares-Velasco , J . J. Toscano

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

We report on a search for pair production of a fourth generation charge -1/3 quark (b') in pbar p collisions at sqrt(s) = 1.8 TeV at the Fermilab Tevatron using an integrated luminosity of 93 pb^-1. Both quarks are assumed to decay via…

High Energy Physics - Experiment · Physics 2012-08-27 D0 Collaboration

Flavor changing neutral currents (FCNC) decays t to H + c, t to Z + c, and H to t + bar{c} are discussed in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions where FCNC decays may take place…

High Energy Physics - Phenomenology · Physics 2009-11-11 R. Gaitan , O. G. Miranda , L. G. Cabral-Rosetti

Flavour Changing Neutral Current (FCNC) decays are forbidden at lowest perturbative order in the Standard Model (SM) and only allowed via quantum loops. These transitions are therefore heavily suppressed in the SM, and New Physics (NP) can…

High Energy Physics - Experiment · Physics 2026-05-19 Christoph Langenbruch

Flavor changing neutral current (FCNC) interactions for a top quark $t$ decays into $Xq$ with $X$ represents a neutral gauge or Higgs boson, and $q$ a up- or charm-quark are highly suppressed in the Standard Model (SM) due to the…

High Energy Physics - Phenomenology · Physics 2018-03-14 P. Q. Hung , Yu-Xiang Lin , Chrisna Setyo Nugroho , Tzu-Chiang Yuan

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

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 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 study the effect of the FCNC on rare $B$ decays in the beyond standard model with vector like singlet quarks. It has been shown that $b \rightarrow s \gamma $ does not receive sizable contribution compared with that of the standard model…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. T. Handoko , T. Morozumi

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

Top quark flavor changing neutral current (FCNC) interactions are highly suppressed in the Standard Model. Therefore, any large signal of FCNCs will indicate the existence of new interactions. In this paper, searches for FCNC interactions…

High Energy Physics - Experiment · Physics 2019-08-15 Efe Yazgan

Anomalous b --> s transitions from LHCb data may suggest a new massive gauge boson Z' that couples to the left-handed b --> s current, which in turn implies a coupling to the t --> c current. In this paper, we study flavor-changing neutral…

High Energy Physics - Phenomenology · Physics 2016-03-23 Kaori Fuyuto , Wei-Shu Hou , Masaya Kohda

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

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

Tree-level Flavor-Changing Neutral Currents (FCNC) are characteristic of models with extra vector-like quarks. These new couplings can strongly modify the B^0 CP asymmetries without conflicting with low--energy constraints. In the light of…

High Energy Physics - Phenomenology · Physics 2011-03-23 G. Barenboim , F. J. Botella , O. Vives

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 the implications of flavour-changing neutral currents (FCNC's) in a model with the $SU(2)_l\times SU(2)_h\times U(1)_Y$ electroweak gauge symmetry for several anomalies appearing in $b\to s \ell\bar \ell$ induced $B$ decays in LHCb…

High Energy Physics - Phenomenology · Physics 2016-04-20 Cheng-Wei Chiang , Xiao-Gang He , German Valencia

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
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