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Related papers: Study of the Top Quark FCNC

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We determine the constraints on the anomalous top-quark coupling associated with the flavor-changing neutral current vertex $\bar t c \gamma $ from the limits on the $b$-quark rare decay $b\rightarrow s \gamma$ and non-standard top-quark…

High Energy Physics - Phenomenology · Physics 2016-08-24 T. Han , K. Whisnant , B. -L. Young , X. Zhang

We derive a strong bound on the chromo-electric dipole moment of the charm quark, and we quantify its impact on models that allow for a sizeable flavour violation in the up quark sector. In particular we show how the constraints coming from…

High Energy Physics - Phenomenology · Physics 2014-05-22 Filippo Sala

A search for single top quark production via flavour changing neutral currents (FCNC) was performed with data collected by the OPAL detector at the e+e- collider LEP. Approximately 600 pb-1 of data collected at sqrt(s) = 189 - 209 GeV were…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL collaboration , G. Abbiendi

Searches for flavor changing neutral currents in top production and decay using data collected by the Compact Muon Solenoid (CMS) experiment at $\sqrt{s}$ = 7 and 8 TeV are presented, corresponding to an integrated luminosity of around 5…

High Energy Physics - Experiment · Physics 2019-08-13 Tae Jeong Kim

We derive bounds on the electric and chromo-electric dipole moments of the charm quark. The second one turns out to be particularly strong, and we quantify its impact on models that allow for a sizeable flavour violation in the up quark…

High Energy Physics - Phenomenology · Physics 2015-06-18 Filippo Sala

We search for the production of single top quarks via flavor-changing neutral current couplings of a gluon to the top quark and a charm (c) or up (u) quark. We analyze 230 pb^{-1} of lepton+jets data from \ppbar collisions at a center of…

High Energy Physics - Experiment · Physics 2008-11-26 D0 Collaboration , V. Abazov

We propose to study the flavor properties of the top quark at the future Circular Electron Positron Collider (CEPC) in China. We systematically consider the full set of 56 real parameters that characterize the flavor-changing neutral…

High Energy Physics - Phenomenology · Physics 2019-11-05 Liaoshan Shi , Cen Zhang

The Effective Field Theory (EFT) approach is widely used in the search for possible deviations from the predictions of the Standard Model. Such an approximation of possible BSM physics is valid up to a certain levels of energy scale and…

High Energy Physics - Phenomenology · Physics 2020-11-24 E. E. Boos , V. E. Bunichev , L. V. Dudko , M. A. Perfilov , G. A. Vorotnikov

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

We calculate single top-quark production at hadron colliders via the chromo-magnetic flavor-changing neutral current couplings $\bar tcg$ and $\bar tug$. We find that the strength for the anomalous $\bar tcg$ ($\bar tug$) coupling may be…

High Energy Physics - Phenomenology · Physics 2016-08-25 T. Han , M. Hosch , K. Whisnant , Bing-Lin Young , X. Zhang

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

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

The electromagnetic dipole moments of the tau lepton and the chromoelectromagnetic dipole moments of the top quark are estimated via flavor-changing neutral currents, mediated by a new neutral massive gauge boson. We predict them in the…

High Energy Physics - Phenomenology · Physics 2018-12-19 J. I. Aranda , D. Espinosa-Gomez , J. Montano , B. Quezadas-Vivian , F. Ramirez-Zavaleta , E. S. Tututi

Extension of the SM with one extra Higgs doublet may give rise to flavor-changing-scalar coupling of a neutral Higgs to a pair of top-charm quarks. This coupling gives rise to a large tree-level effective W^+W^-;ZZ - Higgs - t bar-c…

High Energy Physics - Phenomenology · Physics 2007-05-23 Shaouly Bar-Shalom

The Next Linear Collider(NLC) will provide a excellent tool for probing the detailed nature of the top quark. By extending the recent analysis of Dokshitzer, Khoze and Sterling, we perform a preliminary examination of the influence of an…

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas G. Rizzo

We review the status of the flavour-changing neutral-current processes (FCNC). In particular we discuss: i) Main targets of the field, ii) The theoretical framework for FCNC, iii) Standard analysis of the unitarity triangle, iv)…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras

It is argued that the topcolor models recently proposed by Hill [1] may face significant constraints from flavor-changing neutral current processes (such as $B-\bar{B}$ mixing) unless the mixing angles between down-type quarks are small.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dimitris Kominis

The rate and corresponding gluon jet energy distribution for the process $e^+e^- \to t\bar tg$ are sensitive to the presence of anomalous dipole-like couplings of the top to the photon and $Z$ at the production vertex. For sizeable…

High Energy Physics - Phenomenology · Physics 2007-05-23 Thomas G. Rizzo

We examine the decays $t\rightarrow c\gamma$ and $c Z^0$ in the Standard Model with an extra scalar doublet and no discrete symmetry preventing tree-level flavour changing neutral currents. The Yukawa couplings of the new scalars are…

High Energy Physics - Phenomenology · Physics 2009-10-22 Michael Luke , Martin J. Savage

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
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