Tracking and physics validation studies of the simplified geometry   description with $B^0_{(s)} \to h^+h^{'-}$ decays
  This note validates the usage of the simplified detector geometry description. A sample of $B^0_{(s)} \to h^+h^{'-}$ decays was used to assess the tracking and physics performance with respect to what is obtained with the full detector description. No significant degradation of performance was found. 
M. Gersabeck, E. Rodrigues