Study of the decay $B^0_d \to K^{*0} \mu^+\mu^-$ in ATLAS

A measurement of the muon forward-backward asymmetry $A_{FB}$ and the longitudinal polarization fraction $F_L$ of $K^{*0}$ in the decay $B_d\to K^{*0}\mu^+\mu^-$ as functions of the di-muon invariant mass squared is presented. A data sample of $4.9~\text{fb}^{-1}$ integrated luminosity collected with the ATLAS detector at the Large Hadron Collider in $pp$ collisions at a centre of mass energy $\sqrt{s} = 7$ TeV is used. The measurement is compared to the Standard Model predictions and the results of other experiments.