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Last name: THÉVENIN
First name: F.
Physica Scripta Volume T, 133, p. 4010, http://dx.doi.org./10.1088/0031-8949//t133/014010
This paper presents the results of a detailed investigation of the validity of oscillator strengths in the spectral domain of the Gaia spectrometer 848-875 nm. This analysis is performed by fitting the most significant Fe I and Si I solar lines in this spectral range with synthetic profiles calculated by 3D radiative hydrodynamical (RHD)...
Journal of Physics Conference Series, 130, p. 2001, http://dx.doi.org./10.1088/1742-6596/130/1/012001
Context: Thanks to its proximity, alpha Centauri is an outstanding target for an imaging search for extrasolar planets. Aims: We searched for faint comoving companions to alpha Cen located at angular distances of a few tens of arcseconds, up to 2-3 arcmin. Methods: We obtained CCD images from the NTT-SUSI2 instrument in the Bessel V, R, I, and...
HD 179821 is classified as G5 Ia star. From the IRAS colors and spectral energy distributions it was classified as a post-AGB star. But some studies classify it as a massive (30 to 19 M sun) post-red supergiant evolving to become a Type II supernova. Its mass and evolutionary status remained a hotly debated question even after several detailed...
The effects of background line opacity (line-blocking) in statistical equilibrium calculations for Fe in late-type stellar atmospheres have been investigated using an extensive and up-to-date model atom with radiative data primarily from the Project. The background metal line opacities have been computed using data from the stellar...
Astronomy and Astrophysics, 459, pp. 669-678, http://dx.doi.org./10.1051/0004-6361:5966
Astronomy and Astrophysics, 493, pp. 107-114, http://dx.doi.org./10.1051/0004-6361:200810565
For the nearby dwarf star α Cen B (K1 V), we present limb-darkening predictions from a 3D hydrodynamical radiative transfer model of its atmosphere. We first compared the results of this model to a standard Kurucz's atmosphere. Then we used both predictions to fit the new interferometric visibility measurements of α Cen B obtained with the...
For the nearby dwarf star α Cen B (K1 V), we present limb-darkening predictions from a 3D hydrodynamical radiative transfer model of its atmosphere. We first compared the results of this model to a standard Kurucz's atmosphere. Then we used both predictions to fit the new interferometric visibility measurements of α Cen B obtained with the...
Memorie della Societa Astronomica Italiana Supplement, 77, p. 411 (2006)
Context. Recently the triple-α reaction rate has been re-evaluated. In the temperature range, 107-108 K, with respect to the NACRE rate, the new rate is enhanced by up to 20 orders-magnitude. Aims: To validate this new rate, we investigate its consequences for the evolution of Cepheid models. Methods: The stellar evolutionary tracks are...
Context. Weak G-band (wGb) stars are a very peculiar class of red giants; they are almost devoided of carbon and often present mild lithium enrichment. Despite their very puzzling abundance patterns, very few detailed spectroscopic studies existed up to a few years ago, which prevented any clear understanding of the wGb phenomenon. We recently...
Astronomy and Astrophysics, 436, pp. 253-262, http://dx.doi.org./10.1051/0004-6361:20042075
International audience
International audience
Evolution of the 7Li abundance in the convection zone of the Sun during different stages of its life time is considered to explain its low photospheric value in comparison with that of the solar system meteorites. Lithium is intensively and transiently burned in the early stages of evolution (pre-main sequence, pMS) when the radiative core...
Aims. The nearby metal-poor giant HD 122563 is an important astrophysical laboratory in which to test stellar atmospheric and interior physics. It is also a benchmark star for which to calibrate methods to apply to large scale surveys. Recently it has been remeasured using various methodologies given the new high precision instruments at our...
Astronomy and Astrophysics, 488, pp. 635-642, http://dx.doi.org./10.1051/0004-6361:10011
International audience
The Kepler space telescope yielded unprecedented data for the study of solar-like oscillations in other stars. The large samples of multi-year observations posed an enormous data analysis challenge that has only recently been surmounted. Asteroseismic modeling has become more sophisticated over time, with better methods gradually developing...
Astronomy and Astrophysics, 438, pp. 949-955, http://dx.doi.org./10.1051/0004-6361:20042274