Big-Bang Nucleosynthesis and Galactic Chemical Evolution
نویسندگان
چکیده
Deuterium is the best indicator of the baryon density; however, only its present abundance is known (and only locally) and its chemical evolution is intertwined with that of He. Because galactic abundances are spatially heterogeneous, mean chemical-evolution models are not well suited for extrapolating the pre-solar D and He abundances to their primeval values. We introduce a new approach which explicitly addresses heterogeneity, and show that the decade-old big-bang nucleosynthesis concordance interval η ≈ (2− 8)× 10 based on D and He is robust. submitted to Astrophysical Journal Letters
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