Analysis of the rare decays B⁰→μ⁺μ^- and B_s⁰→μ⁺μ^- at ATLAS

The rare decays B⁰→μ⁺μ^- and B_s⁰→μ⁺μ^- have measurable deviations of their rates from the Standard Model (SM) predictions in many Beyond the Standard Model (BSM) extensions, such as the Minimal Supersymmetric, Minimal Flavor Violation, and Two Higgs-Doublet models. The SM predictions for these decays are in tension with the most recent combined LHC results. The branching ratio measurement uses the reference channel B⁺→J/Ψ[→μ⁺μ^-]K⁺. I will discuss data analysis methods for extraction of the reference channel yield, including Monte Carlo modeling, simultaneous functional fits, and systematic error extraction for the partial Run 2 analysis and for analysis which is in development for the Full Run 2 data.