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Related papers: New global fits to $b \to s$ data with all relevan…

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We perform a model-independent global fit to $b\to s\ell^+\ell^-$ observables to confirm existing New Physics (NP) patterns (or scenarios) and to identify new ones emerging from the inclusion of the updated LHCb and Belle measurements of…

Motivated by recent experimental measurements on flavour physics, in tension with Standard Model predictions, we perform an updated analysis of New Physics violating Lepton Flavour Universality, by using the effective Lagrangian approach…

High Energy Physics - Phenomenology · Physics 2019-09-04 Jorge Alda , Jaume Guasch , Siannah Peñaranda

Lepton universality, meaning the equal coupling of the electroweak gauge bosons to the different lepton flavours, is a central property of the Standard Model (SM). Tests of lepton universality in ratios of rates of $b\to s\ell^+\ell^-$…

High Energy Physics - Experiment · Physics 2023-05-19 Christoph Langenbruch

There are some slight tensions with the SM predictions within the latest LHCb measurements. Besides the known anomaly in one angular observable of the rare decay B -> K* mu+ mu-, another small discrepancy recently occurred. The ratio R_K =…

High Energy Physics - Phenomenology · Physics 2014-12-09 T. Hurth , F. Mahmoudi , S. Neshatpour

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

We discuss the status of $b \to s \ell^+\ell^-$ decays in the post-$R_{K^{(*)}}$ era. The recent LHCb update of $R_K$ and $R_{K^*}$ measurements which are now compatible with the Standard Model, constrain new physics contributions to be…

High Energy Physics - Phenomenology · Physics 2023-10-10 T. Hurth , F. Mahmoudi , S. Neshatpour

Recently the LHCb collaboration has confirmed the evidence for lepton flavour nonuniversality at the $3.1\sigma$ level via an updated measurement of $R_K$. In this work we analyse this evidence within a model-independent approach. We make…

High Energy Physics - Phenomenology · Physics 2021-12-15 T. Hurth , F. Mahmoudi , D. Martinez Santos , S. Neshatpour

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 the Standard Model (SM), the coupling of the electroweak gauge bosons to the leptons is lepton flavour universal. Tests of this property constitute sensitive probes for new physics models that violate lepton flavour universality. Recent…

High Energy Physics - Experiment · Physics 2018-07-01 Christoph Langenbruch

The deviations with respect to the Standard Model that are currently observed in $b \to s \ell\ell$ transitions, or $B$ anomalies, can be interpreted in terms of different New Physics (NP) scenarios within a model-independent effective…

High Energy Physics - Phenomenology · Physics 2019-09-04 Marcel Algueró , Bernat Capdevila , Sébastien Descotes-Genon , Pere Masjuan , Joaquim Matias

Within the standard approach of effective field theory of weak interactions for $\Delta B = 1$ transitions, we look for possibly unexpected subtle New Physics effects, here dubbed "flavourful Easter eggs". We perform a Bayesian global fit…

High Energy Physics - Phenomenology · Physics 2017-10-04 Marco Ciuchini , Antonio M. Coutinho , Marco Fedele , Enrico Franco , Ayan Paul , Luca Silvestrini , Mauro Valli

Ratios of branching fractions of semileptonic B decays, $(B \to H \mu \mu)$ over $(B \to H ee)$ with $H=K, K^*,X_s, K_0(1430), \phi, \ldots$ are sensitive probes of lepton universality. In the Standard Model, the underlying flavor changing…

High Energy Physics - Phenomenology · Physics 2015-06-23 Gudrun Hiller , Martin Schmaltz

One of the fundamental predictions of the Standard Model is Lepton Flavour Universality. Any deviation from this prediction would indicate the existence of physics beyond the Standard Model. Recent LHCb measurements present a pattern of…

High Energy Physics - Phenomenology · Physics 2018-08-21 Yoav Afik , Jonathan Cohen , Eitan Gozani , Enrique Kajomovitz , Yoram Rozen

Using the general, model independent form of the effective Hamiltonian, the general expressions of the longitudinal, normal and transversal polarization asymmetries for (l^-) and (l^+) and combinations of them for the exclusive (B -> K l^+…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. M. Aliev , M. K. Cakmak , A. Ozpineci , M. Savci

The LHCb and Belle collaborations have reported on some anomalies in $b \to s$ transitions, with discrepancies with the Standard Model predictions in some angular observables and branching ratios and intriguing hints for lepton universality…

High Energy Physics - Phenomenology · Physics 2020-01-15 Avelino Vicente

The data on high-precision flavour observables reveal certain puzzles when compared to Standard Model expectations based on a global fit of the CKM unitarity triangle and general theoretical estimates. The discussion of these tensions in…

High Energy Physics - Phenomenology · Physics 2010-11-02 Martin Jung

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

The persisting anomalous data in semileptonic B-decays point towards New Physics models exhibiting large sources of Lepton Flavour Universality Violation. In this work we generalise previous studies by considering frameworks which include…

High Energy Physics - Phenomenology · Physics 2018-11-14 Claudia Cornella , Ferruccio Feruglio , Paride Paradisi

We perform a model-independent analysis of $|\Delta b|=|\Delta d|=1$ processes to test the standard model and probe flavor patterns of new physics. Constraints on Wilson coefficients are obtained from global fits to $B^+ \to \pi^+…

High Energy Physics - Phenomenology · Physics 2023-06-07 Rigo Bause , Hector Gisbert , Marcel Golz , Gudrun Hiller

A range of flavour physics observables show tensions with their corresponding Standard Model expectations: measurements of leptonic flavour-changing neutral current processes and ratios of semi-leptonic branching fractions involving…

High Energy Physics - Phenomenology · Physics 2018-03-28 Johannes Albrecht , Florian Bernlochner , Matthew Kenzie , Stefanie Reichert , David Straub , Alison Tully