Assessing lepton-flavour non-universality from B → K*ℓℓ angular analyses

By B. Capdevila, S. Descotes-Genon, J. Matias, J. Virto. 2016

138 citations recorded by the source corpus.

The recent years of activity at the LHC have brought to light several anomalies in exclusive semileptonic b → sℓ+ℓ− decays. Even though the latest model independent analyses are pointing to sizable New Physics contributions to different Wilson coefficients (especially C9), the possibility of interpreting these results unambiguously in terms of New Physics is spoilt by non-perturbative QCD corrections entering at amplitude level. In this proceeding, we present a brief summary of the latest results of our global fits. Also, the origin of the above mentioned QCD corrections, plus their interplay with possible New Physics contributions, is shortly reviewed. A discussion about the properties of the observable RK leads to the central part of this work: the proposal of a new set of observables able to test for lepton-flavour universality violation, where hadronic uncertainties cancel (in the Standard Model). To conclude, the properties of these observables are analysed within the Standard Model as well as within several New Physics benchmark scenarios.

Subfields: Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/8f98027fe87a8f40ec4138eba7dbddbd529d2a05

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Nuclear and High Energy Physics

Citations in the corpus

Phenomenology of an SU(2) × SU(2) × U(1) model with lepton-flavour non-universality (2016, background): “[147] for other observables in B → K∗`` testing lepton-flavour non-universality.”
Opportunities in Flavour Physics at the HL-LHC and HE-LHC (2018, unknown): “Differences between angular observables in B! Xμμ and B! Xee decays are theoretically pristine [1129, 1130] and are sensitive to different combinations of Wilson coefficients compared to the RX measurements.”
Test of lepton universality in beauty-quark decays (2021, background): “An angular analysis of the electron mode, where SM-like behaviour might be expected in the light of the present results and those from b→ sμ+μ− decays, would allow the formation of ratios between observable quantities other than branching fractions, enabling further precise tests of lepton universal”
New Physics in $${\varvec{b \rightarrow s \ell ^+ \ell ^-}}$$ confronts new data on lepton universality (2019, background): “theoretical and experimental communities [35,36], and may shed new light on this matter [37–39].”
Patterns of New Physics in b → sℓ+ℓ− transitions in the light of recent data (2017, background): “The latter are only important at very low q2, wherever m2`/q 2 is not small compared to 1 (say, below q2 ∼ 1GeV2), and affect in particular the first measured bin in RK∗ .”