Charme, estranheza e o fluxo de energia em colisões hadrônicas

We present and apply to several situations a model for particle production. With this model it is possible to understand the energy flow in hadronic reactions, in photoproduction and also make predictions for the behavior of some observables at higher energies. It is also possible to study the individual contributions of soft and semihard interactions and the individual contributions coming from the central and fragmentation regions. We discuss the charm and strange structure of the nucleon, the meson cloud and their role in fast particle production. We predict, among other things, that an increasing fraction of the reaction energy is going to be released in the central region. As a consequence the asymmetry observed in charm production will decrease.