New Properties of Secondary Cosmic Rays observed by the Alpha Magnetic Spectrometer on the International Space Station

Abstract

Abstract Precise measurements of the secondary cosmic ray fluxes and of secondary-over-primary flux ratios as functions of rigidity are essential for cosmic ray propagation study. We report the properties of heavy secondary cosmic ray fluorine (F) nuclei in the rigidity R range 2GV to 3 TV observed by the Alpha Magnetic Spectrometer experiment (AMS-02) on the International Space Station. The secondary-over-primary ratios fluorine-to-silicon and boron-to-oxygen (or boron-to-carbon) will be discussed, showing that the heavy cosmic rays, from fluorine to silicon, have different propagation properties compared to those of light cosmic rays, from helium to oxygen. The properties of cosmic-ray sodium and aluminum nuclei, which are partly secondary and partly primary, will also be presented.