Related papers: Speckle Interferometry of Red Dwarf Stars

We report the results of a deep photometric search for planets and brown dwarfs in the nearby young OB Upper Scorpius association. We obtained optical (I) and near-infrared (JKs) images around nine very low-mass stars and brown dwarf member…

We present the results of spectroscopic follow-up observations for a sample of 71 red objects with high proper motions in the range 0.08-1.14 arcsec/yr as detected using APM and SSS measurements of multi-epoch photographic Schmidt plates.…

White dwarfs with a F, G or K type companion represent the last common ancestor for a plethora of exotic systems throughout the galaxy, though to this point very few of them have been fully characterised in terms of orbital period and…

We have obtained high contrast images of four nearby, faint, and very low mass objects 2MASSJ04351455-1414468, SDSSJ044337.61+000205.1, 2MASSJ06085283-2753583 and 2MASSJ06524851-5741376 (here after 2MASS0435-14, SDSS0443+00, 2MASS0608-27…

We combine absolute astrometry from Hipparcos and Gaia with archival radial velocities from the Keck/HIRES and ESO/HARPS spectrographs, as well as relative astrometry (when available), to derive masses and orbits for 156 companions around…

Zechmeister et al. (2009) surveyed 38 nearby M dwarfs from March 2000 to March 2007 with VLT2 and the UVES spectrometer. This data has recently been reanalyzed (Butler et al. 2019), yielding a significant improvement in the Doppler velocity…

The orbital parameters of binaries at intermediate periods ($10^2$--$10^3$ d) are difficult to measure with conventional methods and are very incomplete. We have undertaken a new survey, applying our pulsation timing method to {\it Kepler}…

We present an all-sky catalog of M dwarf stars with apparent infrared magnitude J<10. The 8,889 stars are selected from the ongoing SUPERBLINK survey of stars with proper motion >40 mas/yr, supplemented on the bright end with the TYCHO-2…

We present the results of a multiplicity survey for a magnitude-limited sample of 31 classical Be stars conducted with the Navy Precision Optical Interferometer and the Mark III Stellar Interferometer. The interferometric observations were…

Results of 2433 intensified CCD observations of double stars, made with the 26-inch refractor of the U.S. Naval Observatory are presented. Each observation of a system represents a combination of over 2000 short-exposure images. These…

As part of our search for young M dwarfs within 25 pc, we acquired high-resolution spectra of 185 low-mass stars compiled by the NStars project that have strong X-ray emission. By cross-correlating these spectra with radial velocity…

The recently detected TRAPPIST-1 planetary system, with its seven planets transiting a nearby ultracool dwarf star, offers the first opportunity to perform comparative exoplanetology of temperate Earth-sized worlds. To further advance our…

While M dwarfs are the most abundant stars in the Milky Way, there is still large uncertainty about their basic physical properties (mass, luminosity, radius, etc.) as well as their formation environment. Precise knowledge of multiplicity…

We have measured the orbital parameters of seven close binaries, including six new objects, in a radial velocity survey of 38 objects comprising a hot subdwarf star with orbital periods ranging from ~0.17 to 3 d. One new system, GALEX…

We present the first results from an ongoing survey for multiplicity among the bright stars using the Navy Precision Optical Interferometer (NPOI). We first present a summary of NPOI observations of known multiple systems, including the…

We describe a search for close spectroscopic dwarf M star binaries using data from the Sloan Digital Sky Survey (SDSS) to address the question of the rate of occurrence of multiplicity in M dwarfs. We use a template fitting technique to…

We present the results of speckle interferometric observations of 273 magnetic stars most of which are Ap/Bp type. All observations were made at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences.…

Red dwarf stars, which represent 75% of stars in the Milky Way, can be studied in great detail in the solar neighborhood where the sample is more complete. We intend to better characterize red dwarf candidates selected from the Gaia Catalog…

The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact companions (massive white dwarfs M>1.0 Msun, neutron stars or stellar mass black holes). The…

We present projected rotational velocities and new measurements of the rotational profile of some 180 nearby stars with spectral types A-F. The overall broadening profile is derived analysing spectral line shape from hundreds of spectral…