Related papers: Radial Velocity Studies of Close Binary Stars. XI

We have discovered a doubly eclipsing, bound, quadruple star system in the field of K2 Campaign 7. EPIC 219217635 is a stellar image with $Kp = 12.7$ that contains an eclipsing binary (`EB') with $P_A = 3.59470$ d and a second EB with $P_B…

The survey of radial velocity orbits for short period (P < 1 day), bright (V < 10, with a few fainter stars) conducted at the David Dunlap Observatory in the last 9 years before its closure in 2008 included 162 binaries and resulted in 150…

The binary status of gamma-Cas stars has been discussed while theoretically examining the origin of their peculiar X-ray emission. However, except in two cases, no systematic radial velocity monitoring of these stars had been undertaken yet…

Hot subdwarf stars represent a late and peculiar stage in the evolution of low-mass stars, because they are likely formed by close binary interactions. Here we performed a radial velocity (RV) variability study of a sample of 646 hot…

Among the tens of thousands of known RR Lyrae stars there are only a handful that show indications of possible binarity. The question why this is the case is still unsolved, and has recently sparked several studies dedicated to the search…

We present preliminary results of the first and on-going radial velocity survey for circumbinary planets. With a novel radial velocity technique employing an iodine absorption cell we achieve an unprecedented RV precision of up to 2 m/s for…

We present high resolution Laser Guide Star Adaptive Optics imaging of 43 late-M, L and T dwarf systems with Keck/NIRC2. These include 17 spectral binary candidates, systems whose spectra suggest the presence of a T dwarf secondary. We…

Astrometric observations of resolved binaries provide estimates of orbital periods and will eventually lead to measurement of dynamical masses. Only a few very low mass star and brown dwarf masses have been measured to date, and the…

We present new orbital solutions for 15 binaries, which were astrometrically measured during 2010-2013. We observe the binary systems using the FastCam ``lucky-imaging'' camera, installed at the 1.5-m Carlos S\'anchez Telescope (CST) at the…

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…

In the course of our search for double degenerate binaries as potential progenitors of type Ia supernovae with the UVES spectrograph at the ESO VLT (ESO SN Ia Progenitor surveY - SPY) we discovered that the sdB star HE 1047-0436 is radial…

We conducted a radial velocity survey of the Cygnus OB2 Association over a 6 year (1999 - 2005) time interval to search for massive close binaries. During this time we obtained 1139 spectra on 146 OB stars to measure mean systemic radial…

We confirmed four spectroscopic binary candidates using new observations obtained with SALT. Three SB2 systems (HD 20784, HD 43519A, HD 62153A) exhibit circular orbits with periods shorter than 10 days, whereas one hierarchical triple…

We present 2271 radial velocity measurements taken on 118 single-line binary stars, taken over eight years with the CORALIE spectrograph. The binaries consist of F/G/K primaries and M-dwarf secondaries. They were initially discovered…

Eclipsing binaries are vital for directly determining stellar parameters without reliance on models or scaling relations. Spectroscopically derived parameters of detached and semi-detached binaries allow us to determine component masses…

We present time-series spectroscopy and photometry of Gaia DR2 6097540197980557440, a new deeply-eclipsing hot subdwarf B (sdB) + M dwarf (dM) binary. We discovered this object during the course of the Eclipsing Reflection Effect Binaries…

UX Ari belongs to the class of very active RS CVn stars and has recently been the target of surface (Doppler) imaging. Although this technique needs a quite accurate determination of the orbit (in order to have the correct period for…

VW~LMi is the tightest known quadruple system with 2+2 hierarchy. It consists of a W UMa-type eclipsing binary (P12 = 0.47755 days) and another detached non-eclipsing binary (P34 = 7.93 days) orbiting around a common center of mass is about…

Using optical long baseline interferometry, we resolved for the first time the two wide components of HD167971, a candidate hierarchical triple system known to efficiently accelerate particles. Our multi-epoch VLTI observations provide…

We present the results of our spectroscopic observations of eight detached eclipsing binaries (DEBs), selected from the $Kepler$ Eclipsing Binary Catalog. Radial velocities (RVs) were calculated from high resolution spectra obtained with…