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The abundance of lithium measured for the first time beyond our Galaxy

Alessio Muciarelli

Évènements associés

  • Le lundi 8 décembre 2014 de 11:00 à 12:00 - lieu : Salle 108, Bâtiment des Communs - Meudon

The discrepancy between the primordial lithium abundance derived from the Population II dwarf stars and from the predictions of Standard Big Bang Nucleosynthesis is one of the most intriguing and tricky open questions in the modern astrophysics. The use of lower red giant branch stars, instead of the usual method of observing dwarf stars, represents a new approach to attack the problem, allowing to investigate distant, extra-galactic stellar systems for which observations of dwarf stars are precluded because of their faintness. By using FLAMES at VLT observations we have derived for the first time the initial lithium abundance in an extragalactic globular cluster, namely M54 in the Sagittarius galaxy.