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Accueil > Seminar on 2021.03.01 by Eduardo (...) > The abundance of lithium measured (...)

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

Alessio Muciarelli

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.