English
Related papers

Related papers: Flavor Changing Neutral Currents and Left-Right Sy…

200 papers

In the left-right symmetric model based on $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$ gauge symmetry, there appear heavy neutral scalar particles mediating quark flavor changing neutral currents (FCNCs) at tree level. We consider a situation…

High Energy Physics - Phenomenology · Physics 2018-02-14 Naoyuki Haba , Hiroyuki Umeeda , Toshifumi Yamada

We propose a class of Two Higgs Doublet Models where there are Flavour Changing Neutral Currents (FCNC) at tree level, but under control due to the introduction of a discrete symmetry in the full Lagrangian. It is shown that in this class…

High Energy Physics - Phenomenology · Physics 2017-09-20 Joao M. Alves , Francisco J. Botella , Gustavo C. Branco , Fernando Cornet-Gomez , Miguel Nebot

Models with a non-universal Z' exhibit in general flavor changing neutral currents (FCNC) at tree-level. When the Z' couplings favor the third generation, flavor changing transitions of the form Z'tc and Z'tu could be large enough to be…

High Energy Physics - Phenomenology · Physics 2010-09-09 Sudhir Kumar Gupta , G. Valencia

A complete study on the fermion masses and flavor mixing is presented in a non-minimal left-right symmetric model (NMLRMS) where the ${\bf S}_{3}\otimes {\bf Z}_{2}\otimes {\bf Z}^{e}_{2}$ flavor symmetry drives the Yukawa couplings. In the…

High Energy Physics - Phenomenology · Physics 2018-10-30 E. A. Garcés , Juan Carlos Gómez-Izquierdo , F. Gonzalez-Canales

The Flavor Changing Neutral Current decays(FCNC) is forbidden at tree level in the Standard Model (SM) and could only contribute through loops. Any direct observation beyond SM expectations could be a good probe of physics beyond SM. BESIII…

High Energy Physics - Experiment · Physics 2018-11-26 Dayong Wang

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

Flavor symmetric model is one of the attractive Beyond Standard Models (BSMs) to reveal the flavor structure of the Standard Model (SM). A lot of efforts have been put into the model building and we find many kinds of flavor symmetries and…

High Energy Physics - Phenomenology · Physics 2015-05-29 Tatsuo Kobayashi , Yuji Omura , Fumihiro Takayama , Daiki Yasuhara

We perform a systematic reevaluation of the constraints on the flavor-changing neutral current (FCNC) parameters in R-parity conserving and R-parity violating supersymmetric models. As a typical process, we study the constraints coming from…

High Energy Physics - Phenomenology · Physics 2014-11-17 Jyoti Prasad Saha , Anirban Kundu

We investigate a family-nonuniversal Abelian extension of hypercharge, which significantly alters the phenomenological features of the standard model. Anomaly cancellation requires that the third quark family transforms differently from the…

High Energy Physics - Phenomenology · Physics 2024-10-22 N. T. Duy , D. T. Huong , Duong Van Loi , Phung Van Dong

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

We consider a Z' model where the Z' boson couples only to up and top quarks. As a simple setup, one can consider a family-dependent $U(1)'$ symmetry, under which only right-handed up-type quarks are charged. After symmetry breaking, the…

High Energy Physics - Phenomenology · Physics 2020-03-16 Sungwoong Cho , P. Ko , Jungil Lee , Yuji Omura , Chaehyun Yu

In this work we overhaul previous studies of Flavor Changing Neutral Current processes in the context of the Reduced Minimal 3-3-1 model(RM331). We sift the individual contributions from the CP even scalars and the $Z^{\prime}$ gauge boson…

High Energy Physics - Phenomenology · Physics 2015-06-18 D. Cogollo , Farinaldo S. Queiroz , P. Vasconcelos

Aspects of top quark physics can be studied at a future Circular Electron-Positron Collider (CEPC). In particular, Flavor-Changing Neutral Current interactions (FCNC) of the top quark can be studied even with a center-of-mass energy from…

High Energy Physics - Phenomenology · Physics 2022-02-10 M. A. Arroyo-Ureña , J. Lorenzo Díaz-Cruz , R. Gaitán , J. H. Montes de Oca , T. A. Valencia-Pérez

In many extensions of the Standard Model flavour changing neutral current processes can be mediated by tree-level heavy neutral scalars and/or pseudo-scalars H^0(A^0). This generally introduces new sources of flavour violation and CP…

High Energy Physics - Phenomenology · Physics 2013-07-09 Andrzej J. Buras , Fulvia De Fazio , Jennifer Girrbach , Robert Knegjens , Minoru Nagai

Some interpretations of $R_{D^{(*)}}$ anomaly in $B$ meson decay using leptoquark (LQ) models can also generate top quark decays through Flavor Changing Neutral Current (FCNC). In this work we focus on two LQs, i.e. scalar $S_1$ and vector…

High Energy Physics - Phenomenology · Physics 2020-01-08 Tae Jeong Kim , Pyungwon Ko , Jinmian Li , Jiwon Park , Peiwen Wu

Flavour-changing neutral currents are extremely rare processes in the standard model that can be sensitive to various new physics effects. The summary of the latest experimental results from the LHC experiments is given. Preliminary results…

High Energy Physics - Experiment · Physics 2017-11-09 Kirill Skovpen

A search for flavour-changing neutral current (FCNC) events via the coupling of a top quark, a photon, and an up or charm quark is presented using 81 fb$^{-1}$ of proton-proton collision data taken at a centre-of-mass energy of 13 TeV with…

High Energy Physics - Experiment · Physics 2019-12-02 ATLAS Collaboration

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

The flavour-changing neutral currents (FCNC) are derived at tree level if the electroweak gauge group depends on the fermion family, which are absent in the standard model. We study the lepton flavour violation (LFV) through the FCNC…

High Energy Physics - Phenomenology · Physics 2015-05-19 Kang Young Lee

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