Related papers: The subgiant HR 7322 as an asteroseismic benchmark…
Space asteroseismology reveals that stellar structure and evolution models of intermediate- and high-mass stars are in need of improvement in terms of angular momentum and chemical element transport. We aim to probe the interior structure…
The size of convective cores remains uncertain, despite its substantial influence on stellar evolution, and thus on stellar ages. The seismic modeling of young subgiants can be used to obtain indirect constraints on the core structure…
Context. The interpretation of stellar pulsations in terms of internal structure depends on the knowledge of the fundamental stellar parameters. Long-base interferometers permit us to determine very accurate stellar radii, which are…
[Abridged] We present 2.12-2.23 um high contrast integral field spectroscopy of the extrasolar planet HR 8799 b. Our observations were obtained with OSIRIS on the Keck II telescope and sample the 2.2 um CH4 feature, which is useful for…
We present an asteroseismic analysis of 33 solar-type stars observed in short cadence during Campaigns (C) 1-3 of the NASA K2 mission. We were able to extract both average seismic parameters and individual mode frequencies for stars with…
We present Kepler observations of the bright (V=8.3), oscillating star HD 179070. The observations show transit-like events which reveal that the star is orbited every 2.8 days by a small, 1.6 R_Earth object. Seismic studies of HD 179070…
Asteroseismology of dwarf stars cooler than the Sun is very challenging due to the low amplitudes and rapid timescales of oscillations. Here, we present the asteroseismic detection of solar-like oscillations at 4-minute timescales…
Eclipsing binary stars with an oscillating giant component allow accurate stellar parameters to be derived and asteroseismic methods to be tested and calibrated. To this aim, suitable systems need to be firstly identified and secondly…
Metal-poor stars are key to understanding the first stellar generation in the Galaxy. Asteroseismic characterisation of red giants has traditionally relied on global seismic parameters, not the full spectrum of individual oscillation modes.…
Photometric observations made by the NASA Kepler Mission have led to a dramatic increase in the number of main-sequence and subgiant stars with detected solar-like oscillations. We present an ensemble asteroseismic analysis of 76 solar-type…
We present updated parameters for the star HD 209458 and its transiting giant planet. The stellar angular diameter $\theta$=0.2254$\pm$0.0017 mas is obtained from the average ratio between the absolute flux observed with the Hubble Space…
A short observing run with the spectrometer Harps at the ESO 3.6-m telescope was conducted in order to continue exploring the asteroseismic properties of F type stars. In fact, Doppler observations of F type on the main sequence are…
Data from the space missions {\it Gaia}, {\it Kepler}, {\it CoRoT} and {\it TESS}, make it possible to compare parallax and asteroseismic distances. From the ratio of two densities $\rho_{\rm sca}/\rho_{\pi}$, we obtain an empirical…
Asteroseismology provides fundamental stellar parameters independent of distance, but subject to systematics under calibration. Gaia DR2 has provided parallaxes for a billion stars, which are offset by a parallax zero-point. Red Clump (RC)…
Asteroseismology has started to provide constraints on stellar properties that will be essential to accurately reconstruct the history of the Milky Way. Here we look at the information content in data sets representing current and future…
We have obtained H-band interferometric observations of three galactic red supergiant stars using the MIRC instrument on the CHARA array. The targets include AZ Cyg, a field RSG and two members of the Per OB1 association, RS Per and T Per.…
Asteroseismology has proven to be an excellent tool to determine not only the global stellar properties with a good precision but also to infer stellar structure, dynamics, and evolution for a large sample of Kepler stars. Prior to the…
The paper presents a correction to the scaling relations for red-giant stars using model-based masses and radii. We measure radial-mode frequencies from Kepler observations for 3,642 solar-like oscillators on the red-giant branch and use…
Asteroseismology is a powerful tool to measure the fundamental properties of stars and probe their interiors. This is particularly efficient for red giants because their modes are well detectable and give information on their deep layers.…
About 4" south of the young A0-type star HR 7329, a faint companion candidate was found by Lowrance et al. (2000). Its spectral type of M7-8 is consistent with a young brown dwarf companion. Here, we report ten new astrometric imaging…