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Observations of Binary Stars with the Differential Speckle Survey Instrument. IV. Observations of Kepler, CoRoT, and Hipparcos Stars from the Gemini North Telescope

Howell, Steve B.; Ciardi, David R.; Everett, Mark E. +1 more

We present the results of 71 speckle observations of binary and unresolved stars, most of which were observed with the DSSI speckle camera at the Gemini North Telescope in 2012 July. The main purpose of the run was to obtain diffraction-limited images of high-priority targets for the Kepler and CoRoT missions, but in addition, we observed a number…

Wide Companions to Hipparcos Stars within 67 pc of the Sun

Lépine, Sébastien; Tokovinin, Andrei

A catalog of common-proper-motion (CPM) companions to stars within 67 pc of the Sun is constructed based on the SUPERBLINK proper-motion survey. It contains 1392 CPM pairs with angular separations 30'' < ρ < 1800'', relative proper motion between the two components less than 25 mas yr^-1, and magnitudes and colors of the secondarie…

Speckle Interferometry and Orbits of "Fast" Visual Binaries

Tokovinin, Andrei

Results of speckle observations at the 4.1 m SOAR telescope in 2012 (158 measures of 121 systems, 27 non-resolutions) are reported. The aim is to follow fast orbital motion of recently discovered or neglected close binaries and sub-systems. Here, eight previously known orbits are defined better, two more are completely revised, and five orbits are…

Revealing Companions to Nearby Stars with Astrometric Acceleration

Tokovinin, Andrei; Makarov, Valeri V.; Hayward, Thomas L. +1 more

A subset of 51 Hipparcos astrometric binaries among FG dwarfs within 67 pc has been surveyed with the Near-Infrared Coronagraphic Imager adaptive optics system at Gemini-S, directly resolving for the first time 17 subarcsecond companions and 7 wider ones. Using these data together with published speckle interferometry of 57 stars, we compare the s…

On the Nature of the Hot Component in the Symbiotic, Supersoft X-Ray Binary AG Draconis

Sion, Edward M.; Godon, Patrick; Mikolajewska, Joanna +2 more

AG Dra is a symbiotic variable consisting of a metal-poor, yellow giant mass donor underfilling its Roche lobe and a hot accreting white dwarf, possibly surrounded by an optically thick, bright accretion disk (which could be present from wind accretion). We constructed NLTE synthetic spectral models for white dwarf spectra and optically thick accr…

First Orbit and Mass Determinations for Nine Visual Binaries

Ling, J. F.

This paper presents the first published orbits and masses for nine visual double stars: WDS 00149-3209 (B 1024), WDS 01006+4719 (MAD 1), WDS 03130+4417 (STT 51), WDS 04357+3944 (HU 1084), WDS 19083+2706 (HO 98 AB), WDS 19222-0735 (A 102 AB), WDS 20524+2008 (HO 144), WDS 21051+0757 (HDS 3004 AB), and WDS 22202+2931 (BU 1216). Masses were calculated…