B→K^∗νν¯ decays in the Standard Model and beyond

Abstract: We present an analysis of the rare exclusive B decays (Formula presented.) and (Formula presented.) within the Standard Model (SM), in a model-independent manner, and in a number of new physics (NP) models. Combining new form factor determinations from lattice QCD with light-cone sum rule results and including complete two-loop electroweak corrections to the SM Wilson coefficient, we obtain the SM predictions (Formula presented.) and (Formula presented.), more precise and more robust than previous estimates. Beyond the SM, we make use of an effective theory with dimension-six operators invariant under the SM gauge symmetries to relate NP effects in (Formula presented.) transitions to b → sℓ⁺ℓ⁻ transitions and use the wealth of experimental data on B → K^(∗)ℓ⁺ℓ⁻ and related modes to constrain NP effects in (Formula presented.). We then consider several specific NP models, including Z′ models, the MSSM, models with partial compositeness, and leptoquark models, demonstrating that the correlations between (Formula presented.) observables among themselves and with B_s → μ⁺μ⁻ and b → sℓ⁺ℓ⁻ transitions offer powerful tests of NP with new right-handed couplings and non-MFV interactions.