Angular Analysis of $B_{d} \to K^{\ast 0}\mu^{+}\mu^{-}$ with the ATLAS Experiment

A measurement of the forward-backward asymmetry $A_{FB}$ and the fraction of the $K^{\ast 0}$ longitudinal polarisation $F_{L}$ in the decay $B_{d}^{0} \rightarrow K^{\ast 0} \mu^+\mu^-$ as a function of the di-muon invariant mass is presented. A data sample of $4.9\, \text{fb}^{-1}$ of integrated luminosity collected with the ATLAS detector at the LHC at CERN taken in the year 2011 is used. The measurement is compared to the expectations from the Standard Model.