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Related papers: Safe $Z'$ for LFUV

200 papers

Even though the LHC searches did not unveil the new physics particles so far, LHCb hints towards deviations from lepton flavor universality in exclusive decays based on the transition $b\to s\ell\ell$. In this proceeding, we present a new…

High Energy Physics - Phenomenology · Physics 2017-10-25 Olcyr Sumensari

Recent measurements of semileptonic B-meson decays seemingly imply violations of lepton flavor universality beyond the Standard Model predictions. With three-level explanations based on extended Higgs sectors being strongly challenged by…

High Energy Physics - Phenomenology · Physics 2018-08-28 Sean Fraser , Carlo Marzo , Luca Marzola , Martti Raidal , Christian Spethmann

Experimental hints for lepton-flavor universality violation in the muon's magnetic moment as well as neutral- and charged-current $B$-meson decays require Standard-Model extensions by particles such as leptoquarks that generically lead to…

High Energy Physics - Phenomenology · Physics 2022-05-26 Julian Heeck , Anil Thapa

There are indications of a possible breakdown of the standard model, suggesting that $\tau$ lepton interactions violate flavor universality. BABAR, Belle and LHCb report high ratios of $B\to D^{(*)}\tau\nu$. There are long-standing excesses…

High Energy Physics - Phenomenology · Physics 2016-04-13 James M. Cline

In this talk, I will present the status of lepton flavor physics in composite Higgs models with partial compositeness in the light of recent data in the lepton sector. I will consider anarchic flavor setups, scenarios with flavor…

High Energy Physics - Phenomenology · Physics 2021-12-03 Florian Goertz

We define a new class of $Z'$ models with neutral flavor-changing interactions at tree level in the down-quark sector. They are related in an exact way to elements of the quark mixing matrix due to an underlying flavored $U(1)'$ gauge…

High Energy Physics - Phenomenology · Physics 2015-07-17 Alejandro Celis , Javier Fuentes-Martin , Martin Jung , Hugo Serodio

One of the main motivations to look beyond the SM is the discrepancy between the theoretical prediction and observation of anomalous magnetic moment of muon. Alleviating this tension between theory and experiment and satisfying the bounds…

High Energy Physics - Phenomenology · Physics 2021-03-24 Nivedita Ghosh , Jayita Lahiri

Lepton flavor universality in the Standard Model and hints of its violation in neutral ($R_K$) and charged currents $(R_{D^{(*)}})$ in $B$ decays are presented. We discuss model independent features as well as several leptoquark scenarios…

High Energy Physics - Phenomenology · Physics 2016-10-04 Nejc Kosnik

General expressions for one-loop contributions associated with lepton-flavor violating decays of the standard model-like Higgs boson $h\to e_b^\pm e_a^\mp$ and gauge boson $Z\to e^\pm_b e_a^\mp$ are introduced in the unitary gauge. The…

High Energy Physics - Phenomenology · Physics 2024-12-17 L. T. Hue , Khiem Hong Phan , T. T. Hong , T. Phong Nguyen , N. H. T. Nha

Anomalies in (semi)leptonic $B$-meson decays present interesting patterns that might be revealing the shape of the new physics to come. In order to understand the experimental data, we explore symmetry arguments that lead to the hypothesis…

High Energy Physics - Phenomenology · Physics 2015-05-21 Rodrigo Alonso , Benjamín Grinstein , Jorge Martin Camalich

Significant deviations from Standard Model (SM) predictions have been observed in $ b \to s \mu^+ \mu^-$ decays and in the muon $g-2$. Scalar leptoquark extensions of the SM are known to be able to address these anomalies, but generically…

High Energy Physics - Phenomenology · Physics 2021-10-15 Admir Greljo , Peter Stangl , Anders Eller Thomsen

We perform a comprehensive search for Standard Model extensions inspired by asymptotic safety. Our models feature a singlet matrix scalar field, three generations of vector-like leptons, and direct links to the Higgs and flavor sectors via…

High Energy Physics - Phenomenology · Physics 2020-12-30 Gudrun Hiller , Clara Hormigos-Feliu , Daniel F. Litim , Tom Steudtner

We calculate lepton flavor violating Z -> l^+ l^- decay in the framework of the general two Higgs Doublet model. In our calculations we used the constraints for the Yukawa couplings \bar{\xi}^{D}_{N,\tau e} and \bar{\xi}^{D}_{N,\tau\mu}…

High Energy Physics - Phenomenology · Physics 2009-11-07 E. O. Iltan , I. Turan

In recent years, lepton flavour violating (LFV) decays are one of the most trending topics to probe new physics (NP). The latest results of LHCb have motivated us to study the LFV decays through b to s transition. The branching ratios,…

High Energy Physics - Phenomenology · Physics 2023-10-18 S. Biswas , S. Mahata , A. Biswas , S. Sahoo

We discuss the possibility of using the observables deduced from the angular distribution of the $B\to D^{(\ast)} \ell\bar{\nu}$ decays to test the effects of lepton flavor universality violation (LFUV). We show that the measurement of even…

High Energy Physics - Phenomenology · Physics 2019-07-16 Damir Becirevic , Marco Fedele , Ivan Nisandzic , Andrey Tayduganov

Tension between the Standard Model (SM) and data concerning $b \rightarrow s$ processes has become apparent. Most notoriously, concerning the $R_K$ ratio, which probes lepton non-universality in $b$ decays, and measurements involving the…

High Energy Physics - Phenomenology · Physics 2017-03-30 Isabel Garcia Garcia

New sub-GeV vector bosons with couplings to muons but not electrons have been discussed in order to explain the muon's magnetic moment, the gap of high-energy neutrinos in IceCube or the proton radius puzzle. If such a light Z' not only…

High Energy Physics - Phenomenology · Physics 2016-05-11 Julian Heeck

The electroweak sector of the Standard Model contains three generations of charged leptons $\ell^-\in\{e^-,\mu^-,\tau^-\}$ as exact replicas of each other, except for their Yukawa couplings to the Higgs that determine their masses. The…

High Energy Physics - Experiment · Physics 2018-12-04 Biplab Dey

A new heavy $Z'$ vector boson provides a possible explanation for the neutral current B anomalies and points to the scale where we expect the solution to the hierarchy problem to appear. In this paper, we explore a modified Top Seesaw model…

High Energy Physics - Phenomenology · Physics 2023-03-13 Yi Chung

We investigate the implications of scalar and tensor operators proposed to accommodate the hints of lepton flavor universality violation in charged-current $B$-meson decays. We show that these scenarios unavoidably induce chirality enhanced…

High Energy Physics - Phenomenology · Physics 2018-12-26 Ferruccio Feruglio , Paride Paradisi , Olcyr Sumensari