Calculation Of Secondary Particles In Atmosphere And Hadronic   Interactions
  Calculation of secondary particles produced by the interaction of cosmic rays with the nuclei of Earth's atmosphere pose important requirements to particle production models. Here we summarize the important features of hadronic simulations, stressing the importance of the so called ``microscopic'' approach, making explicit reference to the case of the FLUKA code. Some benchmarks are also presented. 
G. Battistoni, A. Ferrari and P.R. Sala