Search Publications
Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs
Thévenin, Frédéric; Kervella, Pierre; Arenou, Frédéric
Context. The multiplicity fraction of stars, down to the substellar regime, is a parameter of fundamental importance for stellar formation, evolution, and planetology. The census of multiple stars in the solar neighborhood is however incomplete.
Aims: Our study is aimed at detecting companions of HIPPARCOS catalog stars from the proper motion…
The Gaia EDR3 view of Johnson-Kron-Cousins standard stars: the curated Landolt and Stetson collections
Rainer, M.; Marinoni, S.; Marrese, P. M. +7 more
Context. In the era of large surveys and space missions, it is necessary to rely on large samples of well-characterized stars for inter-calibrating and comparing measurements from different surveys and catalogues. Among the most employed photometric systems, the Johnson-Kron-Cousins has been used for decades and for a large amount of important dat…
A quarter century of spectroscopic monitoring of the nearby M dwarf Gl 514. A super-Earth on an eccentric orbit moving in and out of the habitable zone
Amado, P. J.; Caballero, J. A.; Reiners, A. +31 more
Context. Statistical analyses based on Kepler data show that most of the early-type M dwarfs host multi-planet systems consisting of Earth- to sub-Neptune-sized planets with orbital periods of up to ~250 days, and that at least one such planet is likely located within the habitable zone. M dwarfs are therefore primary targets to search for potenti…
Precise dynamical masses of new directly imaged companions from combining relative astrometry, radial velocities, and HIPPARCOS-Gaia eDR3 accelerations
Zhang, H.; Ségransan, D.; Udry, S. +7 more
Aims: With an observing time span of more than 20 yr, the CORALIE radial-velocity survey is able to detect long-term trends in data corresponding to companions with masses and separations accessible to direct imaging. Combining exoplanet detection techniques, such as radial velocities from the CORALIE survey, astrometric accelerations from HI…
The origin of early-type runaway stars from open clusters
Heber, U.; Irrgang, A.; Bhat, A.
Runaway stars are ejected from their place of birth in the Galactic disk, with some young B-type runaways found several tens of kiloparsecs from the plane traveling at speeds beyond the escape velocity, which calls for violent ejection processes. Young open clusters are a likely place of origin, and ejection may be either through N-body interactio…
Dynamical masses for two M1 + mid-M dwarf binaries monitored during the SPHERE-SHINE survey
Henning, T.; Messina, S.; D'Orazi, V. +25 more
We present orbital fits and dynamical masses for HIP 113201AB and HIP 36985AB, two M1 + mid-M dwarf binary systems monitored as part of the SPHERE-SHINE survey. To robustly determine the age of both systems via gyrochronology, we undertook a photometric monitoring campaign for HIP 113201 and GJ 282AB, the two wide K star companions to HIP 36985, u…
Analytical determination of orbital elements using Fourier analysis. II. Gaia astrometry and its combination with radial velocities
Ségransan, D.; Delisle, J. -B.
The ESA global astrometry space mission Gaia has been monitoring the position of a billion stars since 2014. The analysis of such a massive dataset is challenging in terms of the data processing involved. In particular, the blind detection and characterization of single or multiple companions to stars (planets, brown dwarfs, or stars) using Gaia a…
Constraining masses and separations of unseen companions to five accelerating nearby stars
Rouan, D.; Schmidt, T. O. B.; Henning, T. +40 more
Aims: In this work, we aim to constrain the masses and separations of potential substellar companions to five accelerating stars (HIP 1481, HIP 88399, HIP 96334, HIP 30314, and HIP 116063) using multiple data sets acquired with different techniques.
Methods: Our targets were originally observed as part of the SPHERE/SHINE survey, and rad…
V1294 Aql = HD 184279: A bad boy among Be stars or an important clue to the Be phenomenon?
Wolf, M.; Chini, R.; Harmanec, P. +21 more
A reliable determination of the basic physical properties and variability patterns of hot emission-line stars is important for understanding the Be phenomenon and ultimately, the evolutionary stage of Be stars. This study is devoted to one of the most remarkable Be stars, V1294 Aql = HD 184279. We collected and analysed spectroscopic and photometr…
Towards a consistent model of the hot quadruple system HD 93206 = QZ Carinæ. I. Observations and their initial analyses
Wolf, M.; Chini, R.; Harmanec, P. +18 more
The hot nine-component system HD 93206, which contains a gravitationally bounded eclipsing Ac1+Ac2 binary (P = 5.9987 d) and a spectroscopic Aa1+Aa2 (P = 20.734 d) binary can provide important insights into the origin and evolution of massive stars. Using archival and new spectra, and a rich collection of ground-based and space photometric observa…