[en] The system Xe + Sn was studied by means of INDRA multidetector at different bombarding energies between 32 and 50 A.MeV. For this system the reaction mechanisms are dominated by binary processes i.e. there are several particle production sources. The existence of a so-called fusion channel is investigated in this work. To search for such events we have first selected those events able to provide through final product detection a good picture of the reaction. A selection of the 'complete' events was first undertaken. So, the utilisation of global variable like flow angle is justified. This angle is issued in the shape analysis of every event and indicates an enhanced energy flow. The isotropic events selected by this method, which represents the shape of an event in the kinetic energy spaces by means of a ellipsoid, correspond to high charged particles multiplicity reactions while their characteristics show that fragments are emitted from a single source. There are presented the center-of-mass distributions of the fragments with Z ≥ 3 which reveal an isotropic production. The light particles detected forward have a isotropic component and a anisotropic component characterized by an emission velocity close to that of the projectile. This anisotropic particles could originate in the first phases of interaction or correspond to residues of the two initial projectile-target nuclei. The properties of the unique source formed in the central collisions are summarized in a table obtained from of an event-by-event analysis of the characteristics of all the fragments and the isotropic part of the light particle production brought to 4 π. The values of < E^*>, < Mimf>, < Z_s>, < Z_s(corr.)> and σ(Z_s, complete) for Xe + Sn at 50 A.MeV and 32 A.MeV are given. To answer the question of fusion or other mechanisms one have to know the characterization of the mechanisms corresponding to intermediate impact parameters. From the present data we can merely state that the characteristics of the selected events correspond to central collisions resulting in a unique source which decays isotropically having a size incorporating almost the entire Xe + Sn