Probing Cosmic Ray Origin With Beryllium and Boron
نویسنده
چکیده
The propagation of cosmic rays through the interstellar medium (ISM) inevitably produces LiBeB nuclei, and the accumulation of these elements over lifetime of galaxy can broadly account for the solar LiBeB abundances. Furthermore, data in old (Population II) stars provides crucial new information: the LiBeB trend versus heavy element abundances traces the Galactic evolution of LiBeB. We summarize the results a careful analysis of the trends among Be, B, Fe, and O. We show that if O/Fe is not constant, as recent data suggest, then the data are consistent with a “standard” cosmic ray origin, wherein the abundances of cosmic ray primaries scale with those of the ISM. On the other hand, if O/Fe is constant, some other cosmic ray origin or component is needed. We suggest future observational tests which will distinguish several recent scenarios of LiBeB and cosmic ray origin.
منابع مشابه
The Galactic Evolution of Beryllium and Boron
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