Related papers: One is the loneliest number: multiplicity in cool …
We investigate the membership in double, triple or higher-order-multiplicity systems of 54 pairs with at least one bright M dwarf in the solar neighbourhood. These M dwarfs are potential targets of radial-velocity surveys for exoplanets. We…
Cool subdwarfs are the oldest members of the low mass stellar population. Mostly present in the galactic halo, subdwarfs are characterized by their low metallicity. Measuring their binary fraction and comparing it to solar metallicity stars…
Multiplicity studies greatly benefit from focusing on M dwarfs because they are often paired in a variety of configurations with both stellar and substellar objects, including exoplanets. We aim to address the observed multiplicity of M…
This doctoral thesis studies stellar multiplicity in the solar neighborhood (d < 10 pc) and in systems hosting planets (d < 100 pc). Using data from the Washington Double Star Catalogue, Gaia DR3, and a comprehensive literature review, it…
The study of stellar multiplicity offers important constraints on the structure of the Galaxy as well as stellar and planet formation and evolution. Focusing on the most immediate solar neighbourhood benefits from obtaining both complete…
Observational advances over the last decade have enabled high-resolution, interferometric studies of forming multiple systems, statistical surveys of multiplicity in star-forming regions, and new insights into disk evolution and planetary…
We present ten new ultra-cool dwarfs in seven wide binary systems discovered using $\textit{Gaia}$ DR2 data, identified as part of our $\textit{Gaia}$ Ultra-Cool Dwarf Sample project. The seven systems presented here include an L1 companion…
Among the hundred or so extrasolar planets discovered to date, 19 are orbiting a component of a double or multiple star system. In this paper, we discuss the properties of these planets and compare them to the characteristics of planets…
We investigate and compare the composition of M-dwarf planets in systems with only one known planet (``singles") to those residing in multi-planet systems (``multis") and the fundamental properties of their host stars. We restrict our…
The properties of multiple stellar systems have long provided important empirical constraints for star formation theories, enabling (along with several other lines of evidence) a concrete, qualitative picture of the birth and early…
We present the discovery of 255 binary and six multiple system candidates with wide > 5" separation composed by ultracool dwarfs companions to stars, plus nine double ultracool dwarf systems. These systems were selected based on common…
- Aims: We intended to quantify the impact of stellar multiplicity on the presence and properties of exoplanets. - Methods: We investigated all exoplanet host stars at less than 100 pc using the latest astrometric data from Gaia DR3 and…
We identify and investigate known late M, L and T dwarfs in the Gaia second data release. This sample is being used as a training set in the Gaia data processing chain of the ultra cool dwarfs work package. We find 695 objects in the…
Cool subdwarfs of types K and M are the fainter counterparts of cool main sequence dwarfs that dominate the Galactic population. In this paper we present the results of an optical speckle survey of 62 confirmed cool subdwarf systems within…
As of August 2008, over 30 multiple exoplanet systems are known, and 28% of stars with planets show significant evidence of a second companion. I briefly review these 30 systems individually, broadly grouping them into five categories: 1)…
The system WDS 16329+0315 is an old, nearby quintuple physical system in the thick Galactic disc formed by a close-resolved, triple primary of solar metallicity, namely HD 149162, and a very wide, common proper motion, secondary pair,…
Determining the orbital eccentricity of an extrasolar planet is critically important for understanding the system's dynamical environment and history. However, eccentricity is often poorly determined or entirely mischaracterized due to poor…
Most stars - especially young stars - are observed to be in multiple systems. Dynamical evolution is unable to pair stars efficiently, which leads to the conclusion that star-forming cores must usually fragment into \geq 2 stars. However,…
Cool M dwarfs outnumber sun-like G stars by ten to one in the solar neighborhood. Due to their proximity, small size, and low mass, M-dwarf stars are becoming attractive targets for exoplanet searches via almost all current search methods.…
The discovered planets in apparent single-planet systems (singles) and those in systems with multiple detected planets (multis) exhibit a rich diversity of physical and orbital properties. We investigate the differences and similarities…