Cross sections for the proton-induced production of He and Ne isotopes from magnesium, aluminum, and silicon

Abstract

We measured integral thin target cross sections for the proton-induced production of the rare gas isotopes 3He, 4He, 20Ne, 21Ne and 22Ne from Mg, Al, and Si from the respective reaction threshold up to 1.6 GeV. These target elements were chosen since they account for more than 50% and 95% of the cosmogenic He and Ne production in extraterrestrial matter, respectively. In order to minimize the influences of secondary particles on the production of residual nuclides a so-called “mini-stack”-approach was used instead of the well known “stacked-foil-technique” for all irradiation experiments with proton energies above 200 MeV. With this new data base a complete and consistent set of excitation functions for the proton-induced production of He and Ne isotopes is established for all target elements relevant for deciphering the cosmic ray record in extraterrestrial matter.