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Related papers: Signals from Flavor Changing Scalar Currents at th…

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In this work, we propose and explore for the first time a new collider signature of heavy neutral scalars typically found in many distinct classes of multi-Higgs models. This signature, particular relevant in the context of the Large Hadron…

High Energy Physics - Phenomenology · Physics 2023-06-14 Pedro M. Ferreira , João Gonçalves , António P. Morais , António Onofre , Roman Pasechnik , Vasileios Vatellis

We discuss $Z$ mediated flavour changing neutral currents within a model where the hierarchical quark and lepton masses are explained via a fourth vector-like family, together with a scalar sector consisting of two Higgs doublets augmented…

High Energy Physics - Phenomenology · Physics 2022-02-08 A. E. Cárcamo Hernández , S. F. King , H. Lee

The LHC is a top quark factory and provides a unique opportunity to look for flavour changing neutral current or charged-lepton flavour violating interactions of the top quark. These processes are highly suppressed in the Standard Model and…

High Energy Physics - Experiment · Physics 2024-01-17 Pavol Bartos

Top decays into a light Higgs boson and an up or charm quark can reach detectable levels in Standard Model extensions with two Higgs doublets or with new exotic quarks, and in the Minimal Supersymmetric Standard Model. Using both a standard…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. A. Aguilar-Saavedra , G. C. Branco

We demonstrate that light charged and extra neutral scalars in the (100-200) GeV mass range pass the potentially dangerous flavor constraints in a particular class of two-Higgs-doublet model which has appropriately suppressed…

High Energy Physics - Phenomenology · Physics 2014-06-24 Gautam Bhattacharyya , Dipankar Das , Anirban Kundu

We solve the strong CP problem in a broad class of two Higgs doublet theories that will be probed at the Large Hadron Collider and at future colliders. These theories feature CP and Abelian flavor symmetries, both broken softly in the…

High Energy Physics - Phenomenology · Physics 2025-06-20 Quentin Bonnefoy , Lawrence J. Hall , Claudio Andrea Manzari , Bea Noether

We present a vacuum of heterotic M-theory whose observable sector has the MSSM spectrum with the addition of one extra pair of Higgs-Higgs conjugate superfields. The quarks/leptons have a realistic mass hierarchy with a naturally light…

High Energy Physics - Theory · Physics 2008-11-26 Michael Ambroso , Volker Braun , Burt A. Ovrut

We study phenomenological constraints on a simple $3-3-1$ model with flavor violating Yukawa couplings. Both triplets Higgs couple to leptons and quarks, which generates flavor violating signals in both lepton and quark sectors. We have…

High Energy Physics - Phenomenology · Physics 2020-05-28 D. T. Huong , N. T. Duy

In this paper, we study the observability of the top-Higgs flavor changing neutral current (FCNC) $tqh$ coupling through the process $pp\to qg\to t(\to \ell^{+}b\nu)h(\to \gamma\gamma)$ at the Large Hadron Collider~(LHC), where $\ell=e,…

High Energy Physics - Phenomenology · Physics 2016-11-18 Yao-Bei Liu , Zhen-Jun Xiao

Flavour-Changing-Neutral-Currents (FCNC) play an important r\^ ole in testing the Standard Model (SM) while probing the possibility of having New Physics beyond the SM. In the SM, FCNC are forbidden at three level, but arise through…

High Energy Physics - Phenomenology · Physics 2013-08-22 G. C. Branco , M. N. Rebelo

The Higgs-fermion couplings are sensitive probes of possible new physics behind a stable light Higgs particle. It is then essential to identify the flavour pattern of those interactions. We consider the case in which a strong dynamics lies…

High Energy Physics - Phenomenology · Physics 2013-09-20 R. Alonso , M. B. Gavela , L. Merlo , S. Rigolin , J. Yepes

We extend the Zee model by introducing a vector-like lepton doublet and a flavor dependent global $U(1)$ symmetry. Flavor changing neutral currents in the quark sector can be naturally forbidden at tree level due to the $U(1)$ symmetry,…

High Energy Physics - Phenomenology · Physics 2021-09-15 Toshinori Matsui , Takaaki Nomura , Kei Yagyu

With no evidence of any exotic particle detected so far beyond the Standard Model, the new physics may lie above the presently accessible energies at colliders and, at low-energies, can be accounted for via an effective description. The…

High Energy Physics - Phenomenology · Physics 2023-08-21 Arturo de Giorgi , Fotis Koutroulis , Luca Merlo , Stefan Pokorski

We consider the phenomenology at the Large Hadron Collider of new heavy vector-like quarks which couple mainly to the third generation quarks via Yukawa interactions, with special emphasis on non-standard doublet representations which are…

High Energy Physics - Phenomenology · Physics 2015-05-30 Giacomo Cacciapaglia , Aldo Deandrea , Naveen Gaur , Daisuke Harada , Yasuhiro Okada , Luca Panizzi

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 discuss a model in which the third generation fermions undergo a different $SU(2)$ weak interaction from the first two generation fermions. In general, a flavor changing neutral current interaction is expected. Constrained by the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ehab Malkawi , Tim Tait , C. --P. Yuan

A search for flavor-changing neutral currents (FCNC) in events with the top quark and the Higgs boson is presented. The Higgs boson decay to a pair of b quarks is considered. The data sample corresponds to an integrated luminosity of 35.9…

High Energy Physics - Experiment · Physics 2018-07-02 CMS Collaboration

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

The top quark flavor changing neutral current (FCNC) process is an excellent probe to search for new physics in top sector since the Standard Model expectation is extremely suppressed. We explore Higgs-mediated top quark FCNC, focusing on…

High Energy Physics - Phenomenology · Physics 2016-01-27 C. S. Kim , Yeo Woong Yoon , Xing-Bo Yuan

We update phenomenological constraints on a Two Higgs Doublet Model with lepton flavour non-conserving Yukawa couplings. We review that $\tan \beta$ is ambiguous in such "Type III" models, and define it from the $\tau$ Yukawa coupling. The…

High Energy Physics - Phenomenology · Physics 2010-06-15 Sacha Davidson , Gerald Grenier