|
Lithium is one of the elements (with deuterium) formed primarily during the primordial nucleosynthesis, a few minutes after the Big-Bang. Its abundance thus allows to determine the quantity of baryons in the Universe. It proves that the density of baryons deduced (or its value Omega-b normalized to the critical density to close the Universe) is much larger than the one visible by radiation. It is therefore essential to better constrain this density of baryons. A recent work on the ESO-VLT of an international consortium, in which take part several astronomers of the Paris Observatory, brings confirmation of the constancy of the lithium abundance in stars, which suggests that the abundance observed is quite close to the primordial abundance, and thus makes it possible to refine the determination of Omega-b.
|