Measurements of the Isotopes of Lithium, Beryllium, and Boron from ACE/CRIS
نویسندگان
چکیده
The isotopes of lithium, beryllium, and boron (LiBeB) are known in nature to be produced primarily by CNO spallation and a a fusion from interactions between cosmic rays and interstellar nuclei. While the dominant source of LiBeB isotopes in the present epoch is cosmic-ray interactions, other sources are known to exist, including the production of Li from big bang nucleosynthesis. Precise observations of galactic cosmic-ray LiBeB in addition to accurate modeling of cosmic-ray transport can help to constrain the relative importance among the different production mechanisms. The Cosmic Ray Isotope Spectrometer (CRIS) on the Advanced Composition Explorer (ACE) has measured nuclei with 2 < Z < 30 in the energy range ~30-500 MeV/nucleon since 1997 with good statistical accuracy. We present measurements of the isotopic abundances of LiBeB and discuss these observations in the context of previous cosmic-ray measurements and spectroscopic observations.
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