The Evolution of 4 He and LiBeB

Our understanding of the evolution of 4 He and 7 Li depends critically on the available data for these two elements at low metallicity. In particular, the degree to which there is a slope in an abundance vs metallicity regression can help determine the evolution of He, C, N, and O in dwarf galaxies in the case of 4 He, and cosmic-ray induced nucleosynthesis of LiBeB in our own galaxy in the case of 7 Li. Recent data and their implications will be discussed.

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