= interaction between 2 slices of beams : [http://flc.web.lal.in2p3.fr/mdi/BBSIM/guineapig++Prod/guineapig++trunk/doc/html/class_guinea.html GUINEA]-method make_step() =


This method gives informations to the object grid_ (lass : GRID), attribute of the class GUINEA, to achieve a time step consisting of : 

 * [wiki:guiNeaPig/DistributeParticle distribute] particles in grid cells
 * computes fields
 * move particles in transverse plane
 * generate and track secondaries