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After an overture and a non-technical exposition of the relevant theoretical framework including a brief discussion of some of the most popular extensions of the Standard Model, we will compile a list of 20 goals in flavour physics that…

High Energy Physics - Phenomenology · Physics 2014-11-20 Andrzej J. Buras

Recently, several new experimental results of the test of lepton flavor universality (LFU) in $B\to D^{(\ast)}$ semi-leptonic decays were announced: the first result of $R_{D}$ from the LHCb Run 1 data, the first results of $R_{D}$ and…

High Energy Physics - Phenomenology · Physics 2024-10-11 Syuhei Iguro , Teppei Kitahara , Ryoutaro Watanabe

Data in $B$-meson decays indicate violations of lepton flavour universality, thereby raising the question about such phenomena in the charm sector. We perform a model-independent analysis of NP contributions in (semi)-leptonic decays of…

High Energy Physics - Phenomenology · Physics 2020-03-18 Robert Fleischer , Ruben Jaarsma , Gabriël Koole

This is a written version of a series of lectures aimed at graduate students in particle theory/string theory/particle experiment familiar with the basics of the Standard Model. We explain the many reasons for the interest in flavour…

High Energy Physics - Phenomenology · Physics 2010-10-14 Y. Nir

331 models constitute an extension of the Standard Model (SM) obtained by enlarging the SM gauge group $SU(3)_\text{C}\times SU(2)_\text{L}\times U(1)_Y$ to the group $SU(3)_\text{C}\times SU(3)_\text{L}\times U(1)_X$. We investigate how a…

High Energy Physics - Phenomenology · Physics 2019-01-14 Sébastien Descotes-Genon , Marta Moscati , Giulia Ricciardi

The flavor-changing neutral current semileptonic decays of $B$ mesons provide an excellent platform for indirectly probing New Physics (NP) beyond the Standard Model (SM). Recent measurements of lepton flavor universality (LFU) ratios such…

High Energy Physics - Phenomenology · Physics 2026-01-08 Md Isha Ali , Utpal Chattopadhyay , Dilip Kumar Ghosh , N Rajeev

In recent years, the LHCb collaboration has published results on the measurement of several observables associated to semileptonic $b \to s$ transitions. Interestingly, various deviations from their expected values in the Standard Model…

High Energy Physics - Phenomenology · Physics 2018-12-10 Avelino Vicente

Here we update the predictions for lepton flavour violating tau and muon decays, $l_j \to l_i \gamma$, $l_j \to 3 l_i$, and $\mu-e$ conversion in nuclei. We work within a SUSY-seesaw context where the particle content of the Minimal…

High Energy Physics - Phenomenology · Physics 2007-10-23 E. Arganda , M. J. Herrero

The flavor changing decays of heavy bottom quarks to the corresponding lighter quarks ($u$, $c$ and $s$) in various $B$-meson decays via charged current and neutral current semileptonic transitions have emerged as promising candidates to…

High Energy Physics - Phenomenology · Physics 2019-08-28 N Rajeev , Rupak Dutta , Suman Kumbhakar

We present a new class of models of lepton flavor in the composite Higgs framework. Following the concept of minimality, they lead to a rich phenomenology in good agreement with the current experimental picture. Because of a unification of…

High Energy Physics - Phenomenology · Physics 2016-07-19 Adrian Carmona , Florian Goertz

After a summary of the motivations for searching flavour violating decays and electric dipole moments in the leptonic sector, I briefly sketch the present status of the limits on lepton-slepton misalignement and discuss the potentialities…

High Energy Physics - Phenomenology · Physics 2007-05-23 Isabella Masina

We propose a mechanism that allows for sizeable flavour violation in quark-lepton currents, while suppressing flavour changing neutral currents in quark-quark and lepton-lepton sectors. The mechanism is applied to the recently proposed 4321…

High Energy Physics - Phenomenology · Physics 2018-12-05 Luca Di Luzio , Javier Fuentes-Martin , Admir Greljo , Marco Nardecchia , Sophie Renner

We present an overview of searches fo violation of lepton flavor universality with focus on low energy precision probes using pions, kaons, tau leptons, and nuclear beta decays. The current experimental results are reviewed, the theoretical…

High Energy Physics - Phenomenology · Physics 2022-10-12 Douglas Bryman , Vincenzo Cirigliano , Andreas Crivellin , Gianluca Inguglia

We perform a global analysis of the bounds from charged lepton flavour violating observables to new physics. We parametrize generic new physics through the Effective Field Theory formalism and perform global fits beyond the common…

High Energy Physics - Phenomenology · Physics 2025-10-07 Enrique Fernández-Martínez , Xabier Marcano , Daniel Naredo-Tuero

In view of recent experimental indications of violations of Lepton Flavor Universality (LFU) in $B$ decays, we analyze constraints and implications of LFU interactions, both using an effective theory approach, and an explicit dynamical…

High Energy Physics - Phenomenology · Physics 2015-07-03 Admir Greljo , Gino Isidori , David Marzocca

New neutral heavy gauge bosons ($Z^\prime$) are predicted within many extensions of the Standard Model. While in case they couple to quarks the LHC bounds are very stringent, leptophilic $Z^\prime$ bosons (even with sizable couplings) can…

High Energy Physics - Phenomenology · Physics 2021-06-30 Andrzej J. Buras , Andreas Crivellin , Fiona Kirk , Claudio Andrea Manzari , Marc Montull

We analyse the rare processes $K \to \pi\nu\bar\nu$ in view of the recent hints of violations of Lepton Flavour Universality (LFU) observed in B meson decays. If, as suggested by present data, the new interactions responsible for LFU…

High Energy Physics - Phenomenology · Physics 2017-10-25 Marzia Bordone , Dario Buttazzo , Gino Isidori , Joachim Monnard

Tests of lepton-universality as rate ratios in $b\to s \ell\ell$ transitions can be predicted very accurately in the Standard Model. The deficits with respect to expectations reported by the LHCb experiment in muon-to-electron ratios of the…

High Energy Physics - Phenomenology · Physics 2020-02-03 Li-Sheng Geng , Benjamín Grinstein , Sebastian Jäger , Jorge Martin Camalich , Xiu-Lei Ren , Rui-Xiang Shi

We give a pedagogical review of flavour and CP violation in the lepton sector, with a particular emphasis on new physics - and in particular supersymmetric - contributions to flavour and CP violating observables involving leptons.

High Energy Physics - Phenomenology · Physics 2007-05-23 Stéphane Lavignac

We review the recent highlights of theoretical flavour physics, based on the theory summary talk given at FPCP2017. Over the past years, a number of intriguing anomalies have emerged in flavour violating $K$ and $B$ meson decays,…

High Energy Physics - Phenomenology · Physics 2017-08-31 Monika Blanke