I'm curious to know what tends to be 'left over' after particle collisions at sites like LHC. I realize that many different particles may arise, depending on the types of particles used for collision, as well as the kinetic energy put into the experiments. Despite the amazing diversity of outcomes these experiments produce, many of these exotic particles are short lived, and most decay almost immediately. What tends to be left over after the decay process has ceased? Are photons the most likely end-result, or is it electrons and protons, etc? Have we truly created new matter that is stable? I know certain things are supposed to be preserved, but I've never heard a good estimate, of what tends to be 'lying around' after everything happens. Particularly, I am wanting to know if we are creating or destroying matter in the end. Thanks!