Related papers: Sub-stellar companions of the young weak-line TTau…

We report the discovery of two binary systems, each consisting of a slightly bloated G-type main-sequence star and an unseen companion, identified through photometric data from TESS and radial velocity variation from Gaia. High-resolution…

Brown-dwarfs are substellar objects with masses intermediate between planets and stars within about 13-80Mjup. While isolated BDs are most likely produced by gravitational collapse in molecular clouds down to masses of a few Mjup, a…

Subdwarf B stars are core-helium burning stars located on the extreme horizontal branch. Extensive mass loss on the red giant branch is necessary to form them. It has been proposed that substellar companions could lead to the required…

The Stellar Planet Survey is an ongoing astrometric search for giant planets and brown dwarfs around a sample of about 30 M-dwarfs. We have discovered several low-mass companions by measuring the motion of our target stars relative to their…

The non-thermal 3.6 cm radio continuum emission from the young stars S1 and DoAr21 in the core of Ophiuchus, has been observed with the Very Long Baseline Array (VLBA) at 6 and 7 epochs, respectively, between June 2005 and August 2006. The…

We report the discovery of a candidate brown dwarf or a very low mass stellar companion (MARVELS-5b) to the star HIP 67526 from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The radial velocity curve for this…

The identification and characterization of massive ($\gtrsim 0.8~M_\odot$) white dwarfs is challenging in part due to their low luminosity. Here we present two candidate single-lined spectroscopic binaries, Gaia DR3 4014708864481651840 and…

Aim: The focus of this paper is on two famous but still poorly understood RV Tauri stars: RV Tau and DF Cyg. We aim at confirming their suspected binary nature and deriving their orbital elements to investigate the impact of their orbits on…

We report the discovery of a 16-20 Jupiter mass radial velocity companion around the very young (~3 Myr) brown dwarf candidate ChaHa8 (M5.75-M6.5). Based on high-resolution echelle spectra of ChaHa8 taken between 2000 and 2007 with UVES at…

Dynamical masses of giant planets and brown dwarfs are critical tools for empirically validating substellar evolutionary models and their underlying assumptions. We present a measurement of the dynamical mass and an updated orbit of PZ Tel…

In 2005, Scholz and collaborators (Scholz et al. 2005) discovered, in a proper motion survey, a young brown dwarf SSSPMJ1102-3431(SSSPMJ1102) of spectral type M8.5, probable member of the TW Hydrae Association (TWA) and possible companion…

Using FORS2 on the Very Large Telescope, we have astrometrically monitored over a period of two months the two components of the brown dwarf system WISE J104915.57-531906.1, the closest one to the Sun. Our astrometric measurements - with a…

We present the results of a survey for stellar and substellar companions to 82 young stars in the nearby OB association Upper Scorpius. This survey used nonredundant aperture-mask interferometry to achieve typical contrast limits of…

Since the beginning of precise Doppler surveys, which have had stunning success in detecting extrasolar planetary companions, one surprising enigma has emerged: the relative paucity of spectroscopic binaries where the secondary mass lies in…

We report limits in the planetary-mass regime for companions around the nearest single white dwarf to the Sun, van Maanen's star (vMa 2), from deep J-band imaging with Gemini North and Spitzer IRAC mid-IR photometry. We find no resolved…

We surveyed thirteen very low mass (VLM; M < 0.2 M_sun) objects in the Taurus star-forming region using near-infrared diffraction-limited imaging techniques on the W.M. Keck I 10 m telescope. Of these thirteen, five were found to be binary,…

The companion GL229B was recently resolved by Xuan et al. (2024) as a tight binary of two brown dwarfs (Ba and Bb) through VLTI-GRAVITY interferometry and VLT-CRIRES+ RV measurements. Here, we present Bayesian models of the interferometric…

We present the spectroscopic orbits of eleven nearby, mid-to-late M dwarf binary systems in a variety of configurations: two single-lined binaries (SB1s), seven double-lined binaries (SB2s), one double-lined triple (ST2), and one…

We report the detection of a substellar companion orbiting the intermediate-mass giant star 11 Com (G8 III). Precise Doppler measurements of the star from Xinglong station and Okayama Astrophysical Observatory (OAO) revealed Keplerian…

Gl 758 B is a late-T dwarf orbiting a metal-rich Sun-like star at a projected separation of $\rho$ $\approx$ 1.6" (25 AU). We present four epochs of astrometry of this system with NIRC2 at Keck Observatory spanning 2010 to 2017 together…