Comparison of Geant4 hadron generation with data from the interactions   with beryllium nuclei of +8.9 GeV/c protons and pions, and of -8 GeV/c pions
  Hadron generation in the Geant4 simulation tool kit is compared with inclusive spectra of secondary protons and pions from the interactions with beryllium nuclei of +8.9 GeV/c protons and pions, and of -8.0 GeV/c pions. The data were taken in 2002 at the CERN Proton Synchrotron with the HARP spectrometer. We report on significant disagreements between data and simulated data especially in the polar-angle distributions of secondary protons and pions. 
A. Bolshakova, et al