A grid of MARCS model atmospheres for late-type stars. I. Methods and general properties
- B. Gustafsson, B. Edvardsson, K. Eriksson, U. Jørgensen, Å. Nordlund, B. Plez
- Physics
- 5 May 2008
Context. In analyses of stellar spectra and colours, and for the analysis of integrated light from galaxies, a homogeneous grid of model atmospheres of late-type stars and corresponding flux spectra…
First stars V - Abundance patterns from C to Zn and supernova yields in the early Galaxy
- R. Cayrel, É. Depagne, B. Nordstrom
- Physics
- 4 November 2003
In the framework of the ESO Large Programme "First Stars", very high-quality spectra of some 70 very metal-poor dwarfs and giants were obtained with the ESO VLT and UVES spectrograph. These stars are…
The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not as Cool as We Thought
- E. Levesque, P. Massey, G. Meynet
- Physics
- 15 April 2005
We use moderate-resolution optical spectrophotometry and the new MARCS stellar atmosphere models to determine the effective temperatures of 74 Galactic red supergiants (RSGs). The stars are mostly…
First stars. I. The extreme r-element rich, iron-poor halo giant CS 31082-001 - Implications for the r-process site(s) and radioactive cosmochronology
We present a high-resolution (R = 75 000, S/N 500) spectroscopic analysis of the bright (V = 11.7), extreme halo giant CS 31082-001 ((Fe/H) = 2.9), obtained in an ESO-VLT Large Programme dedicated to…
The photospheric solar oxygen project. I. Abundance analysis of atomic lines and influence of atmosp
Context: The solar oxygen abundance has undergone a major downward revision in the past decade, the most noticeable one being the update including 3D hydrodynamical simulations to model the solar…
First stars VI - Abundances of C, N, O, Li, and mixing in extremely metal-poor giants. Galactic evolution of the light elements
We have investigated the poorly-understood origin of nitrogen in the early Galaxy by determining N abundances from the NH band at 336 nm in 35 extremely metal-poor halo giants, with carbon and oxygen…
Measurement of stellar age from uranium decay
The observation of this cosmochronometer gives the most direct age determination of the Galaxy, and with improved theoretical and laboratory data, it will provide a highly precise lower limit to the age of the Universe.
The metal–poor end of the Spite plateau
- L. Sbordone, P. Bonifacio, O. D. L. C. D. -. France.
- PhysicsProceedings of the International Astronomical…
- 1 August 2009
Abstract We present the largest sample available to date of lithium abundances in extremely metal poor (EMP) Halo dwarfs. Four Teff estimators are used, including IRFM and Hα wings fitting against 3D…
First stars VIII. Enrichment of the neutron-capture elements in the early Galaxy
- P. François, É. Depagne, F. Primas
- Physics
- 21 September 2007
Context: Extremely metal-poor (EMP) stars in the halo of the Galaxy are sensitive probes of the production of the first heavy elements and the efficiency of mixing in the early interstellar medium.…
A holistic approach to carbon-enhanced metal-poor stars
- T. Masseron, J. Johnson, H Germany
- Physics
- 29 January 2009
Context. Carbon-enhanced metal-poor (CEMP) stars are known to have properties that reflect the nucleosynthesis of the first low- and intermediate-mass stars, because most have been polluted by a no…
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