Abstract
Using an isotope-separator technique, cross sections have been measured for the spallation production of in targets of N, Si, and Mg by protons of 600 MeV and in N by protons of 150 MeV. For 600-MeV protons mb in N, Si, and Mg respectively. For 150-MeV protons mb in N. The results are discussed in terms of the cosmogenic production of in meteorites, lunar surface, cosmic dust, the earth's atmosphere, and the interstellar gas. It is shown that the Si and Mg components of chondritic material will be important sources of , at least as far as the primary galactic flux is concerned. It is also pointed out that the quantitative evaluation of the from lighter nuclei such as oxygen in meteorites and nitrogen in the earth's atmosphere depends strongly on the magnitude of the (unmeasured) secondary-neutron-induced reactions. is shown to be a small fraction of the total Be formed in the spallation of cosmic rays over the whole range of important primary nuclei. Using standard radiochemical techniques cross sections have also been measured for and production in targets of Si and Mg irradiated by 600-MeV protons. The results differ significantly from previously published values.
[NUCLEAR REACTIONS , MeV, , , , , MeV, measured 's. Discuss implications for cosmogenic production of .]
- Received 23 October 1973
DOI:https://doi.org/10.1103/PhysRevC.9.1385
©1974 American Physical Society
