Related papers: The Binary-Binary Hierarchical System XY Leo: A La…
Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: OO Aql, CC Com, V345 Gem, XY Leo, AM Leo, V1010 Oph, V2612 Oph, XX Sex, W UMa, and XY UMa. Most of these…
We present multi-color CCD photometry of the neglected contact binary XZ Leo. Completely covered VRI band light curves and four times of minimum light were obtained. Combining the photometric and previously published radial velocity data, a…
The study of very short-period contact binaries provides an important laboratory in which the most important and problematic astrophysical processes of stellar evolution take place. Short-period contact systems, such as CC Com are…
Close, compact, hierarchical, multiple stellar systems, i.e., multiples having an outer orbital period from months to a few years, comprise a small, but continuously growing group of the triple and multiple star zoo. Many of them consist of…
Roughly half of Solar-type planet hosts have stellar companions, so understanding how these binary companions affect the formation and evolution of planets is an important component to understanding planetary systems overall. Measuring the…
Aims: Detect tertiary components of close binaries from spectroscopy and light curve modelling; investigate light-travel time effect and the possibility of magnetic activity cycles; measure mass-ratios for unstudied systems and derive…
Planets can form and survive in close binaries, although dynamical interactions with the secondary component can actually significantly impact the giant planet formation and evolution. Rare close binaries hosting giant planets offer…
The new discovered short-period close binary star, XY LMi, was monitored photometrically since 2006. It is shown that the light curves are typical EW-type and show complete eclipses with an eclipse duration of about 80 minutes. By analyzing…
In this study we present photometric and spectroscopic variation analysis and orbital period study of a low-mass interacting system OO Aql. Simultaneous solution of the light and radial velocity curves provide us a determination of new set…
At least $70\%$ of massive OBA-type stars reside in binary or higher-order systems. The dynamical evolution of these systems can lend insight into the origins of extreme phenomena such as X-ray binaries and gravitational wave sources. In…
The frequency of multiple systems and their properties are key constraints of stellar formation and evolution. Formation mechanisms of very low-mass (VLM) objects are still under considerable debate and an accurate assessment of their…
Context. The presence of a stellar companion can strongly influence the architecture and long-term stability of planetary systems. Motivated by the discovery of exoplanets exhibiting extremely high eccentricities (e >= 0.8) in systems with…
We have attempted to establish an observational evidence for presence of distant companions which may have acquired and/or absorbed the angular momentum during evolution of multiple systems thus facilitating or enabling formation of contact…
Moderately close binaries are a special class of targets for planet searches. From a theoretical standpoint, their hospitality to giant planets is uncertain and debated. From an observational standpoint, many of these systems present…
Many recent observational studies have concluded that planetary systems commonly exist in multiple-star systems. At least ~20% of the known extrasolar planetary systems are associated with one or more stellar companions. The orbits of…
We study the secular gravitational dynamics of quadruple systems consisting of a hierarchical triple system orbited by a fourth body. These systems can be decomposed into three binary systems with increasing semimajor axes, binaries A, B…
Regular observations by the All Sky Monitor aboard the Rossi X-ray Timing Explorer satellite have yielded well-sampled light-curves with a time baseline of over ten years. We find that up to eight of the sixteen brightest persistent low…
Aims. There are a growing number of giant planets discovered moving around one stellar component of a binary star, most of which have very diverse eccentricity. These discoveries raise the question of their formation and long-term evolution…
We have measured the orbital parameters of seven close binaries, including six new objects, in a radial velocity survey of 38 objects comprising a hot subdwarf star with orbital periods ranging from ~0.17 to 3 d. One new system, GALEX…
Contact binary star systems represent the long-lived penultimate phase of binary evolution. Population statistics of their physical parameters inform understanding of binary evolutionary pathways and end products. We use light curves and…