Related papers: Investigating stellar activity with CoRoT data and…
The nearby (6.5 pc) star HD 219134 was recently shown by Motalebi et al. (2015) and Vogt et al. (2015) to host several planets, the innermost of which is transiting. We present twenty-seven years of radial velocity observations of this star…
The solar-like pulsator HD49385 was observed with the CoRoT satellite during 137 days. The analysis of its oscillation spectrum yielded precise estimates of the mode frequencies over nine radial orders and pointed out some unusual…
Photometric observations of HD~217522 in 1981 revealed only one pulsation frequency $\nu_1=1.21529$~mHz. Subsequent observations in 1989 showed the presence of an additional frequency $\nu_2=2.0174$~mHz. New observations in 2008 confirm the…
A promising way of testing the impact of a magnetic field on internal mixing (core overshooting, internal rotation) in main-sequence B-type stars is to perform asteroseismic studies of a sample of magnetic pulsators. The CoRoT satellite…
Context. Observations and analysis of solar-type oscillations in red-giant stars is an emerging aspect of asteroseismic analysis with a number of open questions yet to be explored. Although stochastic oscillations have previously been…
Empirical evidence suggests a tantalising but unproven link between various indicators of solar activity and the barycentric motion of the Sun. The latter is exemplified by transitions between regular and more disordered motion modulated by…
CoRoT has allowed a quantitative leap for the solar-like-star seismology thanks to 5-month-long uninterrupted timeseries of high-precision photometric data. Kepler is also starting to deliver similar data. Now, several F and G main-sequence…
The presence of g- and p-modes allows testing stellar models from the core to the envelope. Moreover, binarity in an eclipsing system constrains the physical parameters of the pulsating star. CoRot ID 100866999 is a relatively…
The CoRoT space telescope observed nearly 160 000 light curves. Among the most outstanding is that of the young, active planet host star CoRoT-2A. In addition to deep planetary transits, the light curve of CoRoT-2A shows strong rotational…
The present work reports on the discovery of three stars that we have identified to be rotating Sun-like stars, based on rotational modulation signatures inferred from light curves from the CoRoT mission's Public Archives. In our analysis,…
We present our latest results on the solar-stellar connection by studying 18 solar analogs that we identified among the Kepler seismic sample (Salabert et al., 2016a). We measured their magnetic activity properties using observations…
The Microvariability and Oscillations of STars (MOST) photometric satellite has already undertaken more than 64 primary campaigns which include some clusters and has obtained observations of >850 secondary stars of which ~180 are variable.…
A growing number of solar-like oscillations has been detected in red giant stars thanks to CoRoT and Kepler space-crafts. The seismic data gathered by CoRoT on red giant stars allow us to test mode driving theory in physical conditions…
Transmission spectroscopy allows us to detect molecules in planetary atmospheres, but is subject to contamination from inhomogeneities on the stellar surface. Quantifying the extent of this contamination is essential for accurate…
The oscillation frequencies observed in Sun-like stars are susceptible to being shifted by magnetic activity effects. The measured shifts depend on a complex relationship involving the mode type, the field strength and spatial distribution…
We study the response of the low-degree solar p-mode frequencies to the unusual extension of the minimum of solar surface activity since 2007. Helioseismic observations collected by the space-based, Sun-as-a-star GOLF instrument and by the…
Stellar activity strongly affects and may prevent the detection of Earth-mass planets in the habitable zone of solar-type stars with radial velocity technics. Astrometry is in principle less sensitive to stellar activity because the…
A former member of the Hyades cluster, $\iota$ Horologii ($\iota$ Hor) is a planet-hosting Sun-like star which displays the shortest coronal activity cycle known to date ($P_{\rm cyc}\sim$ 1.6 yr). With an age of $\sim$$625$ Myr, $\iota$…
Understanding stellar activity in M dwarfs is fundamental to improving our knowledge of the physics of stellar atmospheres and for planet search programmes. High levels of stellar activity (also with flare events) can cause additional…
Over 2,000 stars were observed for one month with a high enough cadence in order to look for acoustic modes during the survey phase of the Kepler mission. Solar-like oscillations have been detected in about 540 stars. The question of why no…