Beryllium solar abundance

The predictions of this model (normalized to meteoritic abundance for solar metallicity) are illustrated in Fig. 9.6 and compared with observational data for beryllium in stars, based on ground-based measurements of the near-UV Be II doublet A 3130. Assuming that surface Be can suffer some destruction in some of the metal-rich disk stars, there is fair agreement down to about 0.1 of solar abundance, but the secondary trend predicted at still lower metallicities is too steep. 

SNII events alone explain the observed solar abundance distribution between oxygen and chromium. This can be taken as a major theoretical achievement. Complementary sources of hydrogen, helium, lithium, beryllium, boron, carbon and nitrogen are required, and these have been identified. They are the Big Bang, cosmic rays and intermediate-mass stars. Around iron and a little beyond, we must invoke a contribution from type la supernovas (Pig. 8.5). These must be included to reproduce the evolution of iron abundances, a fact which suggests... 

Natural isotopes of beryllium and their solar abundances... 

Beryllium-10 P-decays to 10B with a half-life of 1.5 Myr. Beryllium and boron (along with lithium) are several orders of magnitude less abundant than the other light elements in the solar system because, except for 7Li, they are not produced in stars. They are produced when high-energy cosmic rays, mostly protons, fragment atomic nuclei into small pieces in a process called spallation. Beryllium-10 is constantly being produced at low levels by spallation in the solar system, and its abundance in bulk meteorites is used to estimate the amount of time that they were exposed to cosmic rays as small bodies (their cosmic-ray... 

It is appropriate to begin this lecture with a diagram from the review of Shapiro Silberberg, 1970, which compares the abundances of elements in the cosmic radiation with solar system abundances. This classic measurement is one of the foundations of cosmic-ray physics. The elements lithium, beryllium and boron are quite abundant among cosmic rays even though they constitute only a tiny fraction of the material in the solar system and the interstellar medium. This fact is understood largely as the result of spallation of the... 

The light and fragile elements lithium, beryllium, and boron (LiBeB) are not primarily produced in primordial or stellar nucleosynthesis. In fact, the abundance curve in O Fig. 12.13 shows a huge dip (almost a gap, actually) for the mass numbers 8-11, reflecting the scarcity of LiBeB-nuclei in the solar system. Only the nuclide Li can be produced both in primordial (see Sect. 12.3) and in stellar nucleosynthesis (see Sect. 12.4.2), whereas the nuclides Li, Be, B, and B are almost pure spallation products of heavier elements. 

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