Related papers: Visual Orbits of Spectroscopic Binaries with the C…

Adding to the large radial velocity survey of nearby solar-type stars (summary in Tokovinin, 2023a), spectroscopic orbits are determined for four hierarchical systems: HIP 49442 (inner and outer periods of 164.55 d and 34 yr, respectively),…

We present here the results of astrometric, photometric and spectroscopic observations leading to the determination of the orbit and dynamical masses of the binary L dwarf 2MASSW J0746425+2000321. High angular resolution observations spread…

ASAS photometric observations of LS 1135, an O-type SB1 binary system with an orbital period of 2.7 days, show that the system is also eclipsing. This prompted us to re-examine the spectra used in the previously published spectroscopic…

Combing Gaia DR2 with LAMOST DR5, we spectroscopically identified 924 hot subdwarf stars, among which 32 stars exhibit strong double-lined composite spectra. We measured the effective temperature $T_{\rm eff}$, surface gravity $\log\,g$,…

We present high-precision radial velocity (RV) observations of four solar-type (F7-G5) stars - HD 79498, HD 155358, HD 197037, and HD 220773 - taken as part of the McDonald Observatory Planet Search Program. For each of these stars, we see…

We present observations of the young stars TW Hya and HD 100546 made with the Australia Telescope Compact Array at 89 GHz with $\sim2''$ resolution and $\sim3$ mJy continuum sensitivity. Compact thermal dust continuum emission is detected…

HR 8799 is an hF0 mA5 gamma Doradus, lambda Bootis, Vega-type star best known for hosting four directly imaged candidate planetary companions. Using the CHARA Array interferometer, we measure HR 8799's limb-darkened angular diameter to be…

We present the very first analysis of the spectroscopic variability of the three rapidly rotating Oef stars HD192281 (O5(ef)), HD14442 (O5.5ef) and HD14434 (O6.5(ef)). Radial velocities of the HeII lambda 4541 line reveal no evidence of…

We have obtained low-dispersion IUE spectra of the stars 56 Persei (F4 V) and HR 3643 (F7 II), as part of a survey of late-type stars with a 1565 A flux excess in the TD-1 ultraviolet sky survey. The IUE spectrum of each star reveals the…

Using Chandra we have obtained imaging X-ray spectroscopy of the 10 to 16 Myr old F-star binary HD 113766. We individually resolve the binary components for the first time in the X-ray and find a total 0.3 to 2.0 keV luminosity of 2.2e29…

One of the most effective ways to test stellar evolutionary models is to measure dynamical masses for binary systems at a range of temperatures. In this paper, we present orbits of three young K+M binary systems in Taurus (Hubble~4, FF~Tau,…

We describe radial-velocity time series obtained by HARPS on the 3.60 m telescope in La Silla (ESO, Chile) over ten years and report the discovery of five new giant exoplanets in distant orbits; these new planets orbit the stars HD 564, HD…

Using new data from the UVES spectrograph on the ESO Very Large Telescope and archive images from the Hubble Space Telescope, we have measured projected velocity dispersions and structural parameters for two bright young star clusters in…

Very young massive planets are sufficiently luminous by their internal heat of formation to permit detailed studies, including spectroscopy of their atmospheres with large telescopes at sufficient resolution ($\lambda / \Delta \lambda…

We report on the discovery and validation of a two-planet system around a bright (V = 8.85 mag) early G dwarf (1.43 $R_{\odot}$, 1.15 $M_{\odot}$, TOI 2319) using data from NASA's Transiting Exoplanet Survey Satellite (TESS). Three transit…

Recently, Gauza et al. (2015) reported the discovery of a companion to the late M-dwarf, VHS J125601.92-125723.9 (VHS 1256-1257). The companion's absolute photometry suggests its mass and atmosphere are similar to the HR 8799 planets.…

We present long baseline Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 870$\,\mu$m dust continuum emission and CO (3-2) from the protoplanetary disk around the Herbig Ae/Be star HD 100546, which is one of the few…

The harvest of exoplanet discoveries has opened the area of exoplanet characterisation. But this cannot be achieved without a careful analysis of the host star parameters. The system of HD219134 hosts two transiting exoplanets and at least…

We use photometric and spectroscopic observations of the eclipsing binaries V65, V66 and V69 in the field of the globular cluster M4 to derive masses, radii, and luminosities of their components. The orbital periods of these systems are…

Several nearby solar-type dwarfs with variable radial velocity were monitored to find their spectroscopic orbits. First orbital elements of 15 binaries (HIP 12144, 17895, 27970, 32329, 38636, 39072, 40479, 43004, 73700, 79234, 84696, 92140,…