Halo chemistry and first stars. The chemical composition of the matter in the early Galaxy, from C to Mg†
Monique Spite
(1, 2)
,
Piercarlo Bonifacio
(1, 2, 3)
,
Roger Cayrel
(1, 2)
,
François Spite
(1, 2)
,
Patrick François
(1, 2)
,
Hans-Günter Ludwig
(1, 2, 3)
,
Elisabetta Caffau
(1, 2)
,
Sergei Andrievsky
(4)
,
Beatriz Barbuy
(5)
,
Bertrand Plez
(6)
,
Paolo Molaro
(7)
,
Johannes Andersen
(8)
,
T. Beers
(9)
,
Éric Depagne
(10)
,
Birgitta Nordström
(8)
,
Francesca Primas
(11)
1
GEPI -
Galaxies, Etoiles, Physique, Instrumentation
2 Physique stellaire et galactique
3 CIFIST - Cosmological Impact of the First Stars
4 Department of Astronomy, Odessa Nat. University
5 Departamento de Astronomia, Universidade de São Paulo
6 GRAAL - Groupe de Recherches Autrichiennes et Allemandes. UHB
7 INAF-OATs - INAF-Osservatorio Astronomico di Trieste
8 Niels Bohr Institute, Department of Astrophysics
9 Michigan State University, East Lansing
10 Las Cumbres Observatory, Goleta
11 ESO - European Southern Observatory
2 Physique stellaire et galactique
3 CIFIST - Cosmological Impact of the First Stars
4 Department of Astronomy, Odessa Nat. University
5 Departamento de Astronomia, Universidade de São Paulo
6 GRAAL - Groupe de Recherches Autrichiennes et Allemandes. UHB
7 INAF-OATs - INAF-Osservatorio Astronomico di Trieste
8 Niels Bohr Institute, Department of Astrophysics
9 Michigan State University, East Lansing
10 Las Cumbres Observatory, Goleta
11 ESO - European Southern Observatory
Patrick François
- Fonction : Auteur
- PersonId : 1294615
- ORCID : 0000-0001-8698-2217
Elisabetta Caffau
- Fonction : Auteur
- PersonId : 772584
- ORCID : 0000-0001-6011-6134
- IdRef : 14550266X
Résumé
From NLTE computations of the magnesium abundance in a sample of extremely metal-poor giants we derive [Mg/Fe]= 0.7, leading to [Al/Mg]=-0.80 and [Na/Mg]=-0.85 in the early Galaxy. The ratio [O/Mg] should be near to the solar value. Measurements of nitrogen abundances derived from the analysis of the NH band in eight more stars confirm the large scatter of the ratios [N/Fe] and [N/O] in the early Galaxy.