Abundances of Big Bang elements
نویسنده
چکیده
In this paper we review the present status of observations of the Big Bang elements D, 3He, 4He and 7Li and of their extrapolation to the primordial values. It is shown that, within the errors, the abundances are consistent with the predictions of the standard Big Bang nucleosynthesis for 1 ≤ η10 ≤ 6, which corresponds to 0.004 ≤ Ωbh 2 0 ≤ 0.02. Narrower consistencies in η10 are still possible at ≈ 1.7 or ≈ 4, but in this case some of the observations of D and 4He should be incorrect. Finally, it is noted that extragalactic Li may have already been detected in a star possibly accreted by the Galaxy.
منابع مشابه
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