Related papers: Structure and evolution of low mass W UMa type sys…
The photometric and spectroscopic studies of six contact binaries were performed for the first time. The orbital periods of all the six targets are longer than 0.5d, and we discovered that their mass ratios are smaller than 0.15. So, they…
A catalogue of light curve solutions of contact binary stars has been compiled. It contains the results of 159 light curve solutions. Properties of contact binary stars were studied by using the catalogue data. As it is well known since…
The minimum mass ratio for tidal stability of a contact binary containing two unevolved main-sequence stars is calculated to be $\qmin\simeq0.09$ in the case of a mostly radiative primary, and is higher if an appreciable fraction of the…
The morphology of planetary nebulae emerging from the common envelope phase of binary star evolution is investigated. Using initial conditions based on the numerical results of hydrodynamical simulations of the common envelope phase it is…
Motivated by suggestions that binaries with almost equal-mass components ("twins") play an important role in the formation of double neutron stars and may be rather abundant among binaries, we study the stability of synchronized close and…
The evolution of neutron stars in close binary systems with a low-mass companion is considered assuming the magnetic field to be confined within the solid crust. We adopt the standard scenario of the evolution in a close binary system in…
A photometric and spectroscopic investigation is performed on five W Ursae Majoris eclipsing binaries (EWs) J015818.6+260247 (hereinafter as J0158b), J073248.4+405538 (hereinafter as J0732), J101330.8+494846 (hereinafter as J1013),…
We present a simple analytical method to describe the structure of a spherically expanding envelope with strong mass outflow. The structure is consistently connected to the hydrostatic stellar interior and provides an adequate description…
Massive stars are usually found in binaries, and binaries with periods less than 10 days may have a preference for near equal component masses. In this paper we investigate the evolution of these binaries all the way to contact and the…
In the realm of massive stars, strong binary interaction is commonplace. One extreme case are overcontact systems, which is expected to be part of the evolution of all stars evolving towards a merger, and is hypothesized to play a role in…
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…
In close binary systems composed of a normal, donor star and an accreting neutron star, the amount of material received by the accreting component is, so far, a real intrigue. In the literature there are available models that link the…
We study the evolution of a low mass x-ray binary coupling a binary stellar evolution code with a general relativistic code that describes the behavior of the neutron star. We assume the neutron star to be low--magnetized (B~10^8 G). In the…
Binary and multiple stellar systems are numerous in our solar neighborhood with 80 per cent of the solar-type stars being members of systems with high order multiplicity. The Contact Binaries Towards Merging (CoBiToM) Project is a programme…
In this paper, the first complete photometric light curves in the B, V, and R passbands for an eclipsing binary LO Com are presented, and the photometric solution for the LO Com is derived by analyzing these light curves by using the Wilson…
In sufficiently compact neutron star-white dwarf (NSWD) binary systems, orbital decay means the white dwarf eventually fills its shrinking Roche lobe, initiating a phase of mass transfer. The exchange of angular momentum-both internal and…
Photometric observations in V and I bands of six eclipsing binaries at the lower limit of the orbital periods of W UMa stars are presented. Three of them are newly discovered eclipsing systems. The light curve solutions revealed that all…
Common-envelope (CE) evolution is an outstanding open problem in stellar evolution, critical to the formation of compact binaries including gravitational-wave sources. In the ``classical'' isolated binary evolution scenario for double…
With the ever-increasing number of light curve solutions of contact binary systems increasing number of potential bright red nova progenitors are being reported. There remains, however, only one confirmed event. In the present study we…
A sample of bright contact binary stars (W UMa-type or EW, and related: with beta Lyr light curves, EB, and ellipsoidal, ELL - in effect, all but the detached, EA), to the limit of Vmax = 7.5 magnitude is deemed to include all discoverable…