Related papers: Revisiting symbiotic binaries with interferometry:…
Barium (Ba) dwarfs and CH subgiants are the less-evolved analogues of Ba and CH giants. They are F- to G-type main-sequence stars polluted with heavy elements by a binary companion when the latter was on the Asymptotic Giant Branch (AGB).…
Our long term aim is to derive model-independent stellar masses and distances for long period massive binaries by combining apparent astrometric orbit with double-lined radial velocity amplitudes (SB2). We follow-up ten O+O binaries with…
The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis of subluminous B (sdB) stars in close binary systems with…
The unparalleled photometric data obtained by NASA's Kepler Space Telescope has led to improved understanding of red-giant stars and binary stars. We discuss the characterization of known eccentric system, containing a solar-like…
We show that the evolutionary track of a low-mass red giant should make an extended zigzag on the Hertzsprung-Russel diagram just after the bump luminosity, if fast internal rotation and enhanced extra mixing in the radiative zone bring the…
Photometric time series gathered by space telescopes such as CoRoT and Kepler allow to detect solar-like oscillations in red-giant stars and to measure their global seismic constraints, which can be used to infer global stellar properties…
Wide binaries with hot subdwarf-B (sdB) primaries and main sequence companions are thought to form only through stable Roche lobe overflow (RLOF) of the sdB progenitor near the tip of the red giant branch (RGB). We present the orbital…
The detection of solar-like oscillations in G and K giants with the CoRoT and Kepler space-based satellites allows robust constraints to be set on the mass and radius of such stars. The availability of these constraints for thousands of…
The INTEGRAL satellite has revealed a major population of supergiant High Mass X-ray Binaries in our Galaxy, revolutionizing our understanding of binary systems and their evolution. This population, constituted of a compact object orbiting…
Barium (Ba), CH, and extrinsic or Tc-poor S-type stars are evolved low- and intermediate-mass stars that show enhancement of slow-neutron-capture-process elements on their surface, an indication of mass accretion from a former asymptotic…
We have measured the projected rotational velocities (v sin i) of the mass donors for 29 S-type symbiotic stars using high resolution spectroscopic observations and the cross-correlation function (CCF) method. The results of the CCF have…
Red supergiants (RSGs) are evolved massive stars in a stage preceding core-collapse supernova. Understanding evolved-phases of these cool stars is key to understanding the cosmic matter cycle of our Universe, since they enrich the cosmos…
Long secondary periods (LSPs) occur in about one-third of evolved stars, yet their origin remains unclear. The leading explanations are oscillatory convective modes and a binary companion embedded in dust. We investigate the LSP of the red…
Massive stars deeply influence their surroundings by their luminosity and the injection of kinetic energy. So far, they have mostly been studied with spatially unresolved observations, although evidence of geometrical complexity of their…
Barium stars and technetium-poor, extrinsic S stars are binary systems with a white dwarf companion, and with orbital elements similar to those of symbiotic systems. One may thus wonder whether these various families of binary systems…
SMC 3 is one of the most interesting symbiotic stars. This binary contains a bright K-type giant transferring mass to a massive white dwarf comanion, which makes it is a very promising SN Ia candidate. We discuss the evolutionary status of…
Binary star systems are of particular interest to astronomers because they can be used as astrophysical laboratories to study the properties and processes of stars. Between 70% to 90% of the stars in our galaxy are part of a binary star…
This paper is a follow-up of the vast effort to collect radial velocity data for stars belonging to the Hipparcos survey. We aim at extending the orbital data available for binaries with M giant primaries. The data will be used in the…
We present highlights and an overview of 20 FUSE and HST/STIS observations of the bright symbiotic binary EG And. The main motivation behind this work is to obtain spatially-resolved information on an evolved giant star in order to…
Context. Red giant branch (RGB) stars are very bright objects in galaxies and are often used as standard candles. Interferometry is the ideal tool to characterize the dynamics and morphology of their atmospheres. Aims. We aim at precisely…