Related papers: Orbits and Dynamical Masses for the Active Hyades …

Close-by Earth analogs and super-Earths are of primary importance because they will be preferential targets for the next generation of direct imaging instruments. Bright and close-by G-to-M type stars are preferential targets in radial…

EK Dra (HD 129333) is a young, active, nearby star that is orbited by a low mass companion. By combining new speckle observations with old and new radial velocity measurements we find that the orbit is highly eccentric with e=0.82\pm0.03,…

We report on nine wide common proper motion systems containing late-type M, L, or T companions. We confirm six previously reported companions, and identify three new systems. The ages of these systems are determined using diagnostics for…

We report spectroscopic observations of the nearby, 19.5 yr binary system Gls 67 AB spanning more than 35 yr. We carry out a global orbital solution combining our radial velocity measurements with others from the literature going back more…

The relationship between luminosity and mass is of fundamental importance for direct imaging studies of brown dwarf and planetary companions to stars. In principle this can be inferred from theoretical mass-luminosity models; however, these…

The 30 year orbit of the Cepheid Polaris has been followed with observations by the CHARA Array (Center for High Angular Resolution Astronomy) from 2016 through 2021. An additional measurement has been made with speckle interferometry at…

Mid-infrared (8-13 microns) interferometric data of W Hya were obtained with MIDI/VLTI between April 2007 and September 2009, covering nearly three pulsation cycles. The spectrally dispersed visibility data of all 75 observations were…

We present the detailed fundamental stellar parameters of the close visual binary system; HD39438 for the first time. We used Al-Wardat's method for analyzing binary and multiple stellar systems (BMSSs). The method implements Kurucz's plane…

Using Galactic dynamics we have determined the age of the low mass post-T Tauri stars TW Hya Association (TWA). To do so we applied the method of Ortega et al.(2002, 2004) to five stars of the association with Hipparcos measured distances…

Orbits of inner and outer subsystems in 13 triple or higher-order stellar systems are computed or updated using position measurements and, in three cases, radial velocities. The goal is to determine mutual orbital inclinations, period…

We report spectroscopic observations of HD 27638B, the secondary in a visual binary in which the physically associated primary (separation approximately 19 arcsec) is a B9V star. The secondary shows strong Li 6708 absorption suggesting…

Compact Hierarchical Triples (CHT) are systems with the tertiary star orbiting the inner binary in an orbit shorter than 1000 days. CHT with an eclipsing binary as its inner binary can help us extract a multitude of information about all…

We present our findings based on a detailed analysis for the binaries of the Hyades, in which the masses of the components are well known. We fit the models of components of a binary system to the observations so as to give the observed…

We used very long baseline interferometry to constrain the orbit of the binary system 2MASS J05082729-2101444. We observed the system with the VLBA in three epochs at a frequency of 4.85 GHz, which provides an angular resolution of about 3…

In this paper we present the results of the SPHERE observation of the HD 284149 system, aimed at a more detailed characterisation of both the primary and its brown dwarf companion. We observed HD 284149 in the near-infrared with SPHERE,…

Low-mass and brown dwarfs have recently been found as wide companions to many nearby stars, formerly believed to be single. Wide binaries are usually found as common proper motion pairs. Sometimes, more than two objects share the same large…

Young terrestrial worlds are critical test beds to constrain prevailing theories of planetary formation and evolution. We present the discovery of HD 63433d - a nearby (22pc), Earth-sized planet transiting a young sunlike star (TOI-1726, HD…

We present first results from the Palomar Adaptive Optics Survey of Young Stars conducted at the Hale 5 m telescope. Through direct imaging we have discovered a brown dwarf and two low-mass stellar companions to the young solar-type stars…

HD113337 is a Main-Sequence F6V field star more massive than the Sun, hosting one (possibly two) radial velocity (RV) giant planet(s) and a cold debris disk (marked by an infrared excess). We used the VEGA interferometer on the CHARA array…

We analyze K2 light curves for 132 low-mass ($1\ \gtrsim\ M_*\ \gtrsim\ 0.1$~${M_{\odot}}$) members of the 600--800~Myr-old Hyades cluster and measure rotation periods ($P_{rot}$) for 116 of these stars. These include 93 stars with no prior…