[en] The new LIONS code (Lancement d'IONS or Ion Launching), a dynamical code implemented in the SPIRaL project for the CIME cyclotron studies, is presented. The various software involves a 3D magnetostatic code, 2D or 3D electrostatic codes for generation of realistic field maps, and several dynamical codes for studying the behaviour of the reference particle from the cyclotron center up to the ejection and for launching particles packets complying with given correlations. Its interactions with the other codes are described. The LIONS code, written in Fortran 90 is already used in studying the CIME cyclotron, from the center to the ejection. It is designed to be used, with minor modifications, in other contexts such as for the simulation of mass spectrometer facilities