COSMIC-RAY PRODUCED NITROGEN IN EXTRA TERRESTRIAL MATTER

Production rates of N-15 by both solar cosmic rays (SCR) and galactic cosmic rays (GCR) have been calculated for moon, as well as meteorites of various sizes. Our production rates of N-15 which considered both the reaction channels O-16(p,pn)O-15 and (O(p,2p)N)-O-16-N-15 separate ly are about 30% higher than those by Reedy (1981) who considered only the channel O-16(p,pn)O-15 and used an empirical scaling factor to es timate the contribution from (O(p,2p)N)-O-16-N-15. Production ratio N- 15/Ne-21 is composition dependent and hence is different for various s ilicate minerals. Additionally the ratio N-15/Ne-21 is very sensitive to the energy spectrum of the cosmic rays. This fact can be made use o f in characterizing as well as in decoupling the SCR and GCR effects i n extraterrestrial samples.