ELEMENTAL AND ISOTOPIC COMPOSITION OF THE GALACTIC COSMIC RAYS.

Abstract

The purpose of this review is to record the remarkable advances in recent years in our knowledge of cosmic ray nuclear composition (including anti-nuclei), which led to discovering significant differences in the composition between solar system matter and the matter at the source(s) of the galactic cosmic rays - results having important astrophysical implications. This review discusses the underlying assumptions and biases in determining source abundances and summarizes some of the consequent astrophysical implications. This review is intended for nonspecialists and, therefore, includes a brief summary of cosmic ray physics in addition to tables of measured and source abundances that can be applied to a wide array of astrophysical investigations. However, there are also some new results that may interest investigators in cosmic ray and nuclear astrophysics.