NEW CALCULATION OF ANTIPROTON PRODUCTION BY COSMIC RAY PROTONS AND NUCLEI.

A dramatic increase in the accuracy and statistics of space-borne cosmic ray (CR) measurements has yielded several breakthroughs over the last several years. The most puzzling is the rise in the positron fraction above ~10 GeV over the predictions of the propagation models assuming pure secondary production. The accuracy of the antiproton production cross section is critical for astrophysical applications and searches for new physics since antiprotons in CRs seem to hold the keys to many puzzles including the origin of those excess positrons.

NUCLEAR ENHANCEMENT OF THE PHOTON YIELD IN COSMIC RAY INTERACTIONS.

The concept of the nuclear enhancement factor has been used since the beginning of ray astronomy. It provides a simple and convenient way to account for the contribution of nuclei ( > 1) in cosmic rays (CRs) and in the interstellar medium (ISM) to the diffuse ray emission. An accurate treatment of the dominant emission process, such as hadronic interactions of CRs with the ISM, enables one to study CR acceleration processes and CR propagation in the ISM, and provides a reliable background model for searches of new phenomena.