Test of lepton flavour universality with $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ decays

Abstract

The first test of lepton flavor universality between muons and electrons using $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ ($\ell =e,\mu$) decays is presented. The measurement is performed with data from proton-proton collisions collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$. The ratio of branching fractions between $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{e}^{+}{e}^{-}$ and $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{\mu }^{+}{\mu }^{-}$decays is measured in the dilepton invariant-mass-squared range $1.1<q^2<7.0{\mathrm{GeV}}^2/c^4$ and is found to be $R_{K\pi \pi }^{-1}=1.31_{-0.17}^{+0.18}(\mathrm{stat}){}_{-0.09}^{+0.12}(\mathrm{syst})$, in agreement with the standard model prediction. The first observation of the $B^{+}\to K^{+}{\pi }^{+}{\pi }^{-}{e}^{+}{e}^{-}$ decay is also reported.

arXiv commentAll figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://lbfence.cern.ch/alcm/public/analysis/full-details/1606/ (LHCb public pages)

References in corpus (34)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• Precision Electroweak Measurements on the Z Resonance
• LHCb Detector Performance
• Test of lepton universality using $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• Electroweak Measurements in Electron-Positron Collisions at W-Boson-Pair Energies at LEP
• Test of lepton universality with $B^0\to K^{\ast 0}{\ell }^{+}{\ell }^{-}$ decays
• Kernel Estimation in High-Energy Physics
• More Model-Independent Analysis of b->s Processes
• Explaining $h\to {\mu }^{\pm }{\tau }^{\mp }$, $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ and $B\to K{\mu }^{+}{\mu }^{-}/B\to K{e}^{+}{e}^{-}$ in a two-Higgs-doublet model with gauged $L_{\mu }-L_{\tau }$
• Search for lepton-universality violation in $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• Dressing L_mu - L_tau in Color
• Test of lepton universality in beauty-quark decays
• Efficient, reliable and fast high-level triggering using a bonsai boosted decision tree
• Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
• B-decay Anomalies in a Composite Leptoquark Model
• Family non-universal Z' models with protected flavor-changing interactions
• Lepton Flavor Non-Universality in B-meson Decays from a U(2) Flavor Model
• Test of lepton flavor universality and search for lepton flavor violation in $B\to K\ell \ell$ decays
• Test of lepton universality in $b\to s{\ell }^{+}{\ell }^{-}$ decays
• Measurement of lepton universality parameters in $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ and $B^0\to K^{\ast 0}{\ell }^{+}{\ell }^{-}$ decays
• Improved measurement of the $π\rightarrow \mbox{e} ν$ branching ratio
• LHCb Topological Trigger Reoptimization
• Tests of lepton universality using $B^0\to K_S^0{\ell }^{+}{\ell }^{-}$ and $B^{+}\to K^{\ast +}{\ell }^{+}{\ell }^{-}$ decays
• Reweighting with Boosted Decision Trees
• Test of lepton universality with ${\Lambda }_b^0\to p{K}^{-}{\ell }^{+}{\ell }^{-}$ decays
• Test of lepton flavor universality in B${}^{\pm }$ $\to$ K${}^{\pm }{\mu }^{+}{\mu }^{-}$ and B${}^{\pm }$ $\to$ K${}^{\pm }$e${}^{+}$e${}^{-}$ decays in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Study of the K+ pi+ pi- Final State in B+ -> J/psi K+ pi+ pi- and B+ -> psi-prime K+ pi+ pi-
• First observations of the rare decays $B^{+}->K^{+}{\pi }^{+}{\pi }^{-}{\mu }^{+}{\mu }^{-}$ and $B^{+}->\varphi K^{+}{\mu }^{+}{\mu }^{-}$
• Rate difference between b $\to$ s mu^+ mu^- and b $\to$ s e^+e^- in SUSY with large tan$\beta$
• A general effective field theory description of $b\to s{l}^{+}{l}^{-}$ lepton universality ratios
• Test of lepton flavour universality with $B_s^0\to \varphi {\ell }^{+}{\ell }^{-}$ decays
• Measurement of the ratio of the leptonic widths ${\Gamma }_{ee}/{\Gamma }_{\mu \mu }$ for the $J/\psi$ meson