Direct CP, Lepton Flavor and Isospin Asymmetries in the Decays B->K(*)l+l-

Abstract

We measure rate asymmetries for the rare decays B->K(*)l+l-, where l+l- is either e+e- or mu+mu-, using a sample of 384 million BBbar events collected with the Babar detector at the PEP-II e+e- collider. We find no evidence for direct CP or lepton-flavor asymmetries. For dilepton masses below the J/psi resonance, we find evidence for unexpectedly large isospin asymmetries in both B->Kl+l- and B->K*l+l-, which differ respectively by 3.2 sigma and 2.7 sigma, including systematic uncertainties, from the Standard Model expectations.

7 pages, 3 postscript figures, final version accpeted by PRL; includes EPAPS supplemental material giving full branching fraction results

References in corpus (12)

• The Cosmological Parameters 2006
• Big-Bang nucleosynthesis (Particle Data Group mini-review)
• Weak Decays Beyond Leading Logarithms
• The BABAR Detector
• More Model-Independent Analysis of b->s Processes
• Exclusive radiative and electroweak b->d and b->s penguin decays at NLO
• Improved Model-Independent Analysis of Semileptonic and Radiative Rare B Decays
• CP Asymmetries in bar B -> bar K* (-> bar K pi) l+ l- and Untagged bar B_s,B_s -> phi (-> K+ K-) l+ l- Decays at NLO
• Angular Distributions in the Decays B -> K* l+l-
• Angular Distribution and CP Asymmetries in the Decays B->K^-pi^+e^-e^+ and B->pi^-pi^+e^-e^+
• Forward-backward and isospin asymmetry for B -> K* l+ l- decay in the standard model and in supersymmetry
• Exclusive semileptonic rare decays $B-{>}_{(}$K,K^*) \ell^+ \ell^- in supersymmetric theories

Cited by in corpus (69)

• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of summer 2016
• Symmetries and Asymmetries of B -> K* mu+ mu- Decays in the Standard Model and Beyond
• Measurement of the Differential Branching Fraction and Forward-Backword Asymmetry for B->K(*)l+l-
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2018
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2021
• A facility to Search for Hidden Particles (SHiP) at the CERN SPS
• "Dark" Z implications for Parity Violation, Rare Meson Decays, and Higgs Physics
• Flavor Physics in the Quark Sector
• On B -> V l l at small dilepton invariant mass, power corrections, and new physics
• Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
• Theory of B -> K(*)l+l- decays at high q^2: OPE and quark-hadron duality
• Reassessing the discovery potential of the $B\to K^{\ast }{\ell }^{+}{\ell }^{-}$ decays in the large-recoil region: SM challenges and BSM opportunities
• New constraints on light vectors coupled to anomalous currents
• Phenomenology of a very light scalar (100 MeV $<m_h<$ 10 GeV) mixing with the SM Higgs
• Dark forces coupled to non-conserved currents
• More Benefits of Semileptonic Rare B Decays at Low Recoil: CP Violation
• Observation of the Baryonic Flavor-Changing Neutral Current Decay Lambda_b -> Lambda mu+ mu-
• $B\to K{l}^{+}{l}^{-}$ decay form factors from three-flavor lattice QCD
• Constraints on New Physics in MFV models: a model-independent analysis of Delta F=1 processes
• Constraining the Axion Portal with B -> K l+ l-
• $b\to s$ Transitions in Family-dependent $U(1{)}^{\prime }$ Models
• Measurement of the isospin asymmetry in $B\to K^{(\ast )}{\mu }^{+}{\mu }^{-}$ decays
• $B\to K$ and $D\to K$ form factors from fully relativistic lattice QCD
• New light mediators for the $R_K$ and $R_{K^{\ast }}$ puzzles
• Isospin asymmetries in $B\to (K^{\ast },\rho )\gamma /l^{+}{l}^{-}$ and $B\to K{l}^{+}{l}^{-}$ in and beyond the Standard Model
• Radiative and Electroweak Penguin Decays of B Mesons
• Neutrino Masses and Absence of Flavor Changing Interactions in the 2HDM from Gauge Principles
• Standard Model predictions for $B\to K{\ell }^{+}{\ell }^{-}$, $B\to K{\ell }_1^{-}{\ell }_2^{+}$ and $B\to K\nu \bar{\nu }$ using form factors from $N_f=2+1+1$ lattice QCD
• Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay
• Precision Flavour Physics with $B\to K\nu \bar{\nu }$ and $B\to K{l}^{+}{l}^{-}$
• Rare dileptonic decays of Λ_b in a quark model
• New-physics contributions to the forward-backward asymmetry in B -> K* mu+ mu-
• Bayesian Fit of Exclusive $b\to s\bar{\ell }\ell$ Decays: The Standard Model Operator Basis
• Analysis of $B\to K_J^{\ast }(\to K\pi ){\mu }^{+}{\mu }^{-}$ in the higher kaon resonance region
• Constraints on Relaxion Windows
• $B\to K^{\ast }{l}^{+}{l}^{-}$, $K{l}^{+}{l}^{-}$ decays in a family non-universal $Z^{\prime }$ model
• Branching ratios, forward-backward asymmetries and angular distributions of $B\to K_2^{\ast }{l}^{+}{l}^{-}$ in the standard model and new physics scenarios
• Search for lepton-number violating processes in B+ -> h- l+ l+ decays
• Radiative and Semileptonic B Decays Involving the Tensor Meson K_2^*(1430) in the Standard Model and Beyond
• Light vectors coupled to bosonic currents
• Lepton flavor violation in the Simplest Little Higgs model
• Study of $B\to K^{(\ast )}{\ell }^{+}{\ell }^{-}$ Decays in the Family Non-universal $Z^{\prime }$ Models
• Radiative and Semileptonic B Decays Involving Higher K-Resonances in the Final States
• Precision flavour physics with $B\to K\nu \bar{\nu }$ and $B\to K{l}^{+}{l}^{-}$
• Pair production of dark particles in meson decays
• Constraining new physics with B to K* mu+ mu- in the early LHC era
• Lepton polarization in $B\to K_1{\ell }^{+}{\ell }^{-}$ Decays
• Detecting multimuon jets from the Higgs exotic decays in the Higgs portal framework
• A Search for the Rare Decays B --> pi l+l- and B0 --> eta l+l-
• (B -> K_2 l^+ l^-) decay beyond the Standard Model
• Right-handed Neutrino Dark Matter, Neutrino Masses, and non-Standard Cosmology in a 2HDM
• Study of ${\bar{B}}_s\to K^{(\ast )}{\ell }^{+}{\ell }^{-}$ decays in the PQCD factorization approach with the lattice QCD input
• B to strange tensor meson transition in a model with one universal extra dimension
• Constraints on a New Light Spin-One Particle from Rare b -> s Transitions
• Impact of $Z^{\prime }$ and UED parameters on different asymmetries in $B_s\to \varphi {\ell }^{+}{\ell }^{-}$ decays
• Angular distribution of the FCNC process $B_c\to D_s^{\ast }(\to D_s\pi ){\ell }^{+}{\ell }^{-}$
• Is light thermal scalar dark matter possible?
• Complementarity of Semileptonic $B$ to $K_2^{\ast }(1430)$ and $K^{\ast }(892)$ Decays in the Standard Model with Fourth Generation
• Form factors for $B$ to $Kll$ semileptonic decay from three-flavor lattice QCD
• Rare ${\Lambda }_c$ decays and new physics effects
• Signatures of a Flavor Changing $Z^{\prime }$ Boson in $B_q\to \gamma Z^{\prime }$
• Contribution of low-lying vector resonances to polarization observables in \bar B_d^0 -> \bar K*0 e+ e- decay
• Exploring New Physics in transition $b\to s{\ell }^{+}{\ell }^{-}$ through different $B_c\to D_s^{(\ast )}{\ell }^{+}{\ell }^{-}$ observables
• Tensor form factors of $B\to K_1$ transition from QCD light cone sum rules
• Rare decays of b hadrons
• Lepton universality violation from neutral pion decays in $R_{K^{(\ast )}}$ measurements
• Theoretical Status of Rare B Decays with Muons
• Lepton flavor violating top quark FCNC processes at the $\mu$TRISTAN
• Radiative and Leptonic B-meson Decays from the B-factories