Accelerator Data for Cosmic Ray Physics

I give a brief tour of data from accelerator-based experiments on particle production that are most relevant for understanding high energy cosmic ray showers. The database of particle production in hadron collisions is vast, and I will have to ignore most of it. I decide to focus on the highest energy laboratory collisions, namely hadron colliders, and the highest production cross sections, mostly forward particles. It is therefore far from being a complete review, with a strong bias towards my taste (and knowledge), for which I apologize to nearly everyone. Much of what I leave out is the very high transverse momentum (pT ) small cross section ( ) physics that now dominates the hadron collider eld (weak vector bosons, top quarks, very high pT jets, supersymmetry and Higgs boson searches, etc.). We can suppose these have no relevance to cosmic ray shower development, although when it comes to interactions of primaries with energy E > 10 18 eV, nobody knows. I do not attempt to cover new results to be reported at this symposium by other speakers (from experiments at RHIC; MIPP, CDF, and DZero at Fermilab; ATLAS, CMS, LHCb at the LHC); this is an introductory talk, not a summary. My nal \cut" is Feynman