Related papers: The planetary system host HR\,8799: On its $\lambd…
In 2015, we initiated a survey of Scorpius-Centaurus A-F stars that are predicted to host warm-inner and cold-outer belts of debris similar to the case of the system HR~8799. The survey aims to resolve the disks and detect planets…
The HR 8799 system, with its four giant planets and two debris belts, has an architecture closely mirroring that of our Solar system where the inner, warm asteroid belt and outer, cool Edgeworth-Kuiper belt bracket the giant planets. As…
The atmospheres of gas giant planets are thought to be inhomogeneous due to weather and patchy clouds. We present two full nights of coronagraphic observations of the HR 8799 planets using the CHARIS integral field spectrograph behind the…
CoRoT and Kepler missions are now providing high-quality asteroseismic data for a large number of stars. Among intermediate-mass and massive stars, fast rotators are common objects. Taking the rotation effects into account is needed to…
The Rocky Planet Search (RPS) program is dedicated to a blind radial velocity (RV) search of planets around bright stars in the Northern hemisphere, using the high-resolution echelle spectrograph HARPS-N installed on the Telescopio…
Gamma Doradus stars (hereafter gamma Dor stars) are gravity-mode pulsators of spectral type A or F. Such modes probe the deep stellar interior, offering a detailed fingerprint of their structure. Four-year high-precision space-based Kepler…
The analysis of a dense time-series on V974 Oph disclosed the rich pulsational content (at least five independent terms) of this high-amplitude (0.60 mag in B-light) Delta Sct star. A mode with a frequency very close to the main one…
With four years of nearly-continuous photometry from Kepler, we are finally in a good position to apply asteroseismology to $\gamma$ Doradus stars. In particular several analyses have demonstrated the possibility to detect non-uniform…
We have analysed the photometric data obtained with the STEREO spacecraft for 558 non-magnetic chemically peculiar (CP) stars to search for rotational and pulsational variability. Applying the Lomb-Scargle and the phase dispersion…
We use precise radial velocity measurements and photometric data to derive the frequency spacing of the p-mode oscillation spectrum of the planet-hosting star Beta Gem. This spacing along with the interferometric radius for this star is…
HR 8799 is a four planet system that also hosts a debris disk. By numerically integrating both planets and a planetesimal disk, we find interactions between an exterior planetesimal disk and the planets can influence the lifetime of the…
The extrasolar planetary system around HR 8799 is the first multiplanet system ever imaged. It is also, by a wide margin, the highest mass system with >27 Jupiters of planetary mass past 25 AU. This is a remarkable system with no analogue…
Context. Gamma Doradus (hereafter $\gamma$~Dor) stars are gravity-mode pulsators whose periods carry information about the internal structure of the star. These periods are especially sensitive to the internal rotation and chemical mixing,…
One of the goals of the ground-based support program for the COROT and MONS/Roemer satellite missions is to select and characterise suitable target stars for the part of the missions dedicated to asteroseismology. While the global…
We present a pre-discovery H-band image of the HR 8799 planetary system that reveals all three planets in August 2007. The data were obtained with the Keck adaptive optics system, using angular differential imaging and a coronagraph. We…
HD 179949 is an F8V star, orbited by a giant planet at ~8 R* every 3.092514 days. The system was reported to undergo episodes of stellar activity enhancement modulated by the orbital period, interpreted as caused by Star-Planet Interactions…
The theory the rotational and chemical evolution is incomplete, thereby limiting the accuracy of model-dependent stellar mass and age determinations. The $\gamma$ Doradus pulsators are excellent points of calibration for the current…
The Transiting Exoplanet Survey Satellite (TESS) is recording short-cadence, high duty-cycle timeseries across most of the sky, which presents the opportunity to detect and study oscillations in interesting stars, in particular planet…
The near-infrared colors of the planets directly imaged around the A star HR 8799 are much redder than most field brown dwarfs of the same effective temperature. Previous theoretical studies of these objects have concluded that the…
We present the current status of and new results from our search for exoplanets in a sample of solar-mass, evolved stars observed with the HARPS-N and the 3.6-m Telescopio Nazionale Galileo (TNG), and the High Resolution Spectrograph (HRS)…