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The primordial Helium abundance

V. Luridiana
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Abstract

The primordial abundance of 4He, Y_P, is one of the hottest themes in present-day astronomy, mostly due to its cosmological relevance. The disagreement between different determinations has been currently reduced to the 1-2 percent level, but these differences are still large enough to have deep implications for Big-Bang nucleosynthesis. It is therefore crucial to estimate precisely the uncertainties involved in the measurement of Y_P. Here, I review the methods used in the determination of Y_P and the related uncertainties. I also discuss some recent results, and emphasize the assumptions underlying the differences among them.

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V. Luridiana. 2002-09-10. The primordial Helium abundance. https://arxiv.org/abs/astro-ph/0209177

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