Spallation, cosmic rays, meteorites, and planetology

In this review article we present some of the major applications for cosmogenic nuclide studies; extraterrestrial applications on meteorites, lunar surface samples but also on interstellar grains and terrestrial applications ranging from ages for exposure and burial over erosion and denudation rates to uplift and soil dynamics. For all the applications a good knowledge of the cosmogenic nuclide production rates is indispensable. Since it is neither possible nor feasible measuring production rates for all possible set-ups and geometries they are usually calculated using the particle spectra for primary and secondary particles and the cross sections for the relevant nuclear reactions. Considering the reacting particles we also discuss in some detail the basic properties of solar and galactic cosmic rays, especially we focus on the temporal variability. With a good understanding of the projectile types, a very relevant step is to understand and model the induced nuclear reactions. In doing so, we will briefly discuss the basic properties of spallation reactions and we especially focus on the recent very impressive improvements. We finish with a short outlook of the next possible steps for further improvements