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Related papers: New binaries in the epsilon Cha association

200 papers

A total of 28 young nearby stars (ages $\leq 60$,Myr) have been observed in the K$_{\rm s}$-band with the adaptive optics imager Naos-Conica of the Very Large Telescope at the Paranal Observatory in Chile. Among the targets are ten visual…

We report the discovery of companions to 5 nearby late M dwarfs (>M5), LHS1901, LHS4009, LHS6167, LP869-26 and WT460, and we confirm that the recently discovered mid-T brown dwarf companion to SCR1845-6357 is physically bound to that star.…

The pre-main sequence star CHXR74 (M4.25) in ChaI was detected a few years ago to be a very low-mass spectroscopic binary. Determination of its mass would provide a valuable dynamical mass measurement at young ages in the poorly constrained…

Solar and Stellar Astrophysics · Physics 2015-06-03 V. Joergens , M. Janson , A. Müller

We report the first results of a multi-epoch search for wide (separations greater than a few tens of AU), low-mass tertiary companions of a volume-limited sample of 118 known spectroscopic binaries within 30 pc of the Sun, using the 2MASS…

Solar and Stellar Astrophysics · Physics 2015-06-05 Peter R. Allen , Adam J. Burgasser , Jacqueline K. Faherty , J. Davy Kirkpatrick

The aim of the project is to improve our knowledge on the multiplicity of planet-host stars at wide physical separations. We cross-matched approximately 6200 square degree area of the Southern sky imaged by the Visible Infrared Survey…

Earth and Planetary Astrophysics · Physics 2014-10-08 N. Lodieu , A. Perez-Garrido , V. J. S. Bejar , B. Gauza , M. T. Ruiz , R. Rebolo , D. J. Pinfield , E. L. Martin

The results of long-term surveys of radial velocities of cool Ap and Am stars are presented. There are two samples, one of about 100 Ap stars and the other of 86 Am stars. Both have been observed with the CORAVEL scanner from Observatoire…

Astrophysics · Physics 2007-05-23 P. North , N. Ginestet , J. -M. Carquillat , F. Carrier , S. Udry

We present the results of an adaptive optics survey for faint companions among Galactic O-type star systems (V < 8) using the Advanced Electro-Optical System (AEOS) 3.6-meter telescope on Haleakala. We surveyed these O star systems in…

The star-forming regions in Chamaeleon are one of the nearest (distance ~165 pc) and youngest (age ~2 Myrs) conglomerates of recently formed stars and the ideal target for population studies of star formation. We investigate a total of 16…

Solar and Stellar Astrophysics · Physics 2015-06-04 N. Vogt , T. O. B. Schmidt , R. Neuhäuser , A. Bedalov , T. Roell , A. Seifahrt , M. Mugrauer

Orbits of 55 visual binary stars are computed using recent speckle interferometry data from the SOAR telescope: 33 first-time orbits and 22 revisions of previous orbit calculations. The orbital periods range from 1.4 to 370 years, the…

Solar and Stellar Astrophysics · Physics 2016-08-04 Andrei Tokovinin

We report the discovery of 14 low-mass binary systems containing mid-M to mid-L dwarf companions with separations larger than 250 AU. We also report the independent discovery of 9 other systems with similar characteristics that were…

We present the first results of a multi-year program to map the orbits of M dwarf multiples within 25 parsecs. The observations were conducted primarily during 2019 - 2020 using speckle interferometry at the Southern Astrophysical Research…

Solar and Stellar Astrophysics · Physics 2022-03-30 Eliot Halley Vrijmoet , Andrei Tokovinin , Todd J. Henry , Jennifer G. Winters , Elliott Horch , Wei-Chun Jao

As a part of our ongoing Volume-limited A-Star (VAST) adaptive optics survey, we have obtained observations of 26 binary systems with projected separations <100 AU, 13 of which have sufficient historical measurements to allow for refinement…

We present the results of a speckle interferometric survey of Galactic massive stars that complements and expands upon a similar survey made over a decade ago. The speckle observations were made with the KPNO and CTIO 4 m telescopes and…

Orbital motions in four hierarchical stellar systems discovered by speckle interferometry are studied. Their inner orbits are relatively well constrained, while the long outer orbits are less certain. The eccentric and misaligned inner…

Solar and Stellar Astrophysics · Physics 2023-04-05 Andrei Tokovinin

The very young brown dwarf candidate ChaHa8 was recently discovered to have a close (~1AU) companion by means of radial velocity monitoring. We present additional radial velocity data obtained with UVES/VLT between 2007 and 2010, which…

Solar and Stellar Astrophysics · Physics 2015-05-19 V. Joergens , A. Mueller , S. Reffert

We describe an astrometric and spectroscopic campaign to confirm the youth and association of a complete sample of candidate wide companions in Taurus and Upper Sco. Our survey found fifteen new binary systems (3 in Taurus and 12 in Upper…

Solar and Stellar Astrophysics · Physics 2015-05-13 Adam L. Kraus , Lynne A. Hillenbrand

The solar galactic neighbourhood contains a number of young co-moving associations of stars (so-called `young moving groups') with ages of ~10--150 Myr, which are prime targets for a range of scientific studies, including direct imaging…

The latest results from our ongoing multiplicity study of (Community) TESS Objects of Interest are presented, using astro- and photometric data from the ESA-Gaia mission, to detect stellar companions of these stars and characterize their…

Solar and Stellar Astrophysics · Physics 2022-08-24 M. Mugrauer , J. Zander , K. -U. Michel

We conducted a survey of nearby binary systems composed of main sequence stars of spectral types F and G in order to improve our understanding of the hierarchical nature of multiple star systems. Using Robo-AO, the first robotic adaptive…

We present the latest results of our ongoing multiplicity study of (Community) TESS Objects of Interest, using astro- and photometric data from the ESA-Gaia mission, to detect stellar companions of these stars and to characterize their…

Solar and Stellar Astrophysics · Physics 2021-10-04 M. Mugrauer , K. -U. Michel