Elisabetta Caffau

Overview of the lithium problem in metal-poor stars and new results on 6Li (2008)

Cayrel, Roger, Steffen, Matthias, Bonifacio, Piercarlo, Ludwig, Hans-Günter, Caffau, Elisabetta

Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang...

Overview of the lithium problem in metal-poor stars and new results on 6Li (2008)

Cayrel, Roger, Steffen, Matthias, Bonifacio, Piercarlo, Ludwig, Hans-Günter, Caffau, Elisabetta

Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang...

Overview of the lithium problem in metal-poor stars and new results on 6Li (2008)

Cayrel, Roger, Steffen, Matthias, Bonifacio, Piercarlo, Ludwig, Hans-Günter, Caffau, Elisabetta

Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang...

The solar photospheric abundance of hafnium and thorium. Results from CO5BOLD 3D hydrodynamic model atmospheres. (2008)

Caffau, Elisabetta, Sbordone, L., Bonifacio, P., Steffen, M., Behara, N.T.

Context: The stable element hafnium (Hf) and the radioactive element thorium (Th) were recently suggested as a suitable pair for radioactive dating of stars. The applicability of this elemental pair...

The solar photospheric abundance of hafnium and thorium. Results from CO5BOLD 3D hydrodynamic model atmospheres. (2008)

Caffau, Elisabetta, Sbordone, L., Bonifacio, P., Steffen, M., Behara, N.T.

Context: The stable element hafnium (Hf) and the radioactive element thorium (Th) were recently suggested as a suitable pair for radioactive dating of stars. The applicability of this elemental pair...

The photospheric solar oxygen project: I. Abundance analysis of atomic lines and influence of atmospheric models (2008)

Caffau, Elisabetta, Ludwig, Hans-G., Steffen, Matthias, R. Ayres, Thomas, Bonifacio, Piercarlo, Cayrel, Roger, ...

The solar oxygen abundance has undergone a major downward revision in the last decade, the most noticeable one being the update including 3D hydrodynamical simulations to model the solar photosphere....

The photospheric solar oxygen project: I. Abundance analysis of atomic lines and influence of atmospheric models (2008)

Caffau, Elisabetta, Ludwig, Hans-G., Steffen, Matthias, R. Ayres, Thomas, Bonifacio, Piercarlo, Cayrel, Roger, ...

The solar oxygen abundance has undergone a major downward revision in the last decade, the most noticeable one being the update including 3D hydrodynamical simulations to model the solar photosphere....

Overview of the lithium problem in metal-poor stars and new results on 6Li (2008)

Cayrel, Roger, Steffen, Matthias, Bonifacio, Piercarlo, Ludwig, Hans-Günter, Caffau, Elisabetta

Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang...

Overview of the lithium problem in metal-poor stars and new results on 6Li (2008)

Cayrel, Roger, Steffen, Matthias, Bonifacio, Piercarlo, Ludwig, Hans-Günter, Caffau, Elisabetta

Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang...

The forbidden 1082 nm line of sulphur: the photospheric abundance of sulphur in the Sun and 3D effects (2007)

Caffau, Elisabetta, Ludwig, Hans-Guenter

Sulphur is an element which is formed in the alpha-process and is easily measured in the gaseous phase in external galaxies. Since it does not form dust, it is the preferred indicator for...

Sulphur abundances from the SI near-infrared triplet at 1045 nm (2007)

Caffau, Elisabetta, Faraggiana, Rosanna, Bonifacio, Piercarlo, Ludwig, Hans-G., Steffen, Matthias

context : Unlike silicon and calcium, sulphur is an alpha-element which does not form dust. Some of the available observations of the evolution of sulphur with metallicity indicate an increased...

The solar photospheric abundance of phosphorus: results from co5bold 3D model atmospheres (2007)

Caffau, Elisabetta, Steffen, Matthias, Sbordone, Luca, Ludwig, Hans-G., Bonifacio, Piercarlo

aims: We determine the solar abundance of phosphorus using co5bold 3D hydrodynamic model atmospheres. method: High resolution, high signal-to-noise solar spectra of the PI lines of Multiplet 1 at...

Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination (2007)

Cayrel, Roger, Steffen, Matthias, Chand, Hum, Bonifacio, Piercarlo, Spite, Monique, Spite, François, ...

Context: Line asymmetries are generated by convective Doppler shifts in stellar atmospheres, especially in metal-poor stars, where convective motions penetrate to higher atmospheric levels. Such...

Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination (2007)

Cayrel, Roger, Steffen, Matthias, Chand, Hum, Bonifacio, Piercarlo, Spite, Monique, Spite, François, ...

Context: Line asymmetries are generated by convective Doppler shifts in stellar atmospheres, especially in metal-poor stars, where convective motions penetrate to higher atmospheric levels. Such...

The solar photospheric abundance of phosphorus: results from co5bold 3D model atmospheres (2007)

Caffau, Elisabetta, Steffen, Matthias, Sbordone, Luca, Ludwig, Hans-G., Bonifacio, Piercarlo

aims: We determine the solar abundance of phosphorus using co5bold 3D hydrodynamic model atmospheres. method: High resolution, high signal-to-noise solar spectra of the PI lines of Multiplet 1 at...

Sulphur abundances from the SI near-infrared triplet at 1045 nm (2007)

Caffau, Elisabetta, Faraggiana, Rosanna, Bonifacio, Piercarlo, Ludwig, Hans-G., Steffen, Matthias

context : Unlike silicon and calcium, sulphur is an alpha-element which does not form dust. Some of the available observations of the evolution of sulphur with metallicity indicate an increased...

The forbidden 1082 nm line of sulphur: the photospheric abundance of sulphur in the Sun and 3D effects (2007)

Caffau, Elisabetta, Ludwig, Hans-Guenter

Sulphur is an element which is formed in the alpha-process and is easily measured in the gaseous phase in external galaxies. Since it does not form dust, it is the preferred indicator for...