  The ATF2 project aims at demonstrating the strong vertical electron beam
focusing capability, down to the few tens of nanometers level, of a down scale
prototype of the final focus system of the next generation of e+e- machines.
ATF2 offers opportunities to check in a real accelerator environment case for
the performances of the beam transport and background generation code, used in
the simulation of the future e+e- machines, BDSIM, and for the performances of
its underneath particle-matter simulation code, Geant4.
