Related papers: The triple system AT Mic AB + AU Mic in the beta P…
There are a variety of different techniques available to estimate the ages of pre-main-sequence stars. Components of physical pairs, thanks to their strict coevality and the mass difference, such as the binary system analysed in this paper,…
We discuss the properties of companions to B stars in the Scorpius-Centaurus association (age ~15 Myr, 181 B-stars). We gathered available data combining high contrast imaging samples with evidence of companions from Gaia, from eclipsing…
Determining the precise ages of young (tens to a few hundred Myr) kinematic (``moving") groups is important for placing star, protoplanetary disk, and planet observations on an evolutionary timeline. The nearby $\sim$25 Myr-old $\beta$…
The origin of very low-mass hydrogen-burning stars, brown dwarfs, and planetary-mass objects at the low-mass end of the initial mass function is not yet fully understood. Gravitational fragmentation of circumstellar discs provides a…
We have carried out a multi-band photometric monitoring of the close visual binary GJ3039, consisting of a M4 primary and a fainter secondary component, and likely member of the young stellar association $\beta$ Pictoris (24-Myr old). From…
Magnetic cycles have been detected in tens of solar-like stars. The relationship between the cycle properties and global stellar parameters is not fully understood yet. We searched for activity cycles in 90 solar-like stars with ages…
In 1981, Beta Pictoris showed strong and rapid photometric variations possibly due to a transiting giant planet. Later, a planetary mass companion to the star, Beta Pic b, was identified using imagery. Observations at different epochs (2003…
We present 75 new stellar rotation periods in the young cluster IC348. Stars estimated to be less massive than 0.25 Mo show a unimodal distribution with a peak at P ~1-2 d) and a tail of slower rotators, while stars estimated to be more…
We characterize the impact of several sources of systematic errors on the computation of the traceback age of the $\beta$ Pictoris Moving Group ($\beta$PMG). We find that uncorrected gravitational redshift and convective blueshift bias…
We present photometric, astrometric, and spectroscopic observations of USco160611.9-193532 AB, a candidate ultrawide (~1600 AU), low-mass (M_tot~0.4 M_sun) multiple system in the nearby OB association Upper Scorpius. We conclude that both…
In this paper we present an analysis of near-infrared spectropolarimetric and velocimetric data of the young M dwarf AU Mic, collected with SPIRou at the Canada-France-Hawaii telescope from 2019 to 2022, mostly within the SPIRou Legacy…
We present a comparison between the rotation period distributions of solar-type single stars and primary stars in close binaries (0.1 AU ~< a ~< 5 AU) in the young (150 Myr) open cluster M35 (NGC 2168). We find that the primary stars in the…
We investigate the orbital dynamics of four-planet systems consisting of Earth-mass planets on initially-circular, coplanar orbits around a star of one solar mass. In our simulations, the innermost planet's semimajor axis is set at 1 AU,…
Some chemically peculiar stars in the upper main sequence show rotational period variations of unknown origin. We propose these variations are a consequence of the propagation of internal waves in magnetic rotating stars that lead to the…
We present Multiband Imaging Photometer for Spitzer (MIPS) observations at 24 and 70 microns for 30 stars, and at 160 microns for a subset of 12 stars, in the nearby (~30 pc), young (~12 Myr) Beta Pictoris Moving Group (BPMG). In several…
We present deep HST/STIS coronagraphic images of the Beta Pic debris disk obtained at two epochs separated by 15 years. The new images and the re-reduction of the 1997 data provide the most sensitive and detailed views of the disk at…
Star ADS 9173=WDS 14135+5147=Hip 69483 is a complex system. The B component has a spectroscopic companion, whose orbit with a period of 4.9 years has been known since 1986. The Gaia telescope has detected a distant faint pair over 100…
This paper aims to precisely determine the masses and detect pulsation modes in the two massive components of Beta Cen with BRITE-Constellation photometry. In addition, seismic models for the components are considered and the effects of…
In this study, we conducted a comprehensive analysis of the SX Phoenicis (SX Phe) type star CY Aquarii (CY Aqr). Our investigation included a detailed $O-C$ analysis based on a 90-year observational dataset, augmented by 1,367 newly…
We present Lick Natural Guide Star Adaptive Optics observations of the L8 brown dwarf Gliese 337C, which is resolved for the first time into two closely separated (0"53+/-0"03), nearly equal magnitude components with a K_s flux ratio of…