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Binarity among stellar clusters in galaxy is such a reality which has been realized for a long time, but still hides several questions and problems to be solved. Some of binary star clusters are formed by close encounter, but the others are formed together from similar womb. Some of them undergo separation process, while the others are in the middle of merger toward common future. The products of merger binary star cluster have typical characteristics which differ from solo clusters, especially in their spatial distribution and their stellar members kinematics. On the other hand, these merger products still have to face dissolving processes triggered by both internal and external factors. In this study, we performed N-body simulations of merger binary clusters with different initial conditions. After merging, these clusters dissolve with greater mass-loss rate because of their angular momentum. These rotating clusters also experience more deceleration caused by external tidal field. [ABSTRACT FROM AUTHOR]

A few binary systems display High Energy (100 MeV-100 GeV) and/or Very High Energy (>= 100 GeV) gamma-ray emission. These systems also display non-thermal radio emission+that can be resolved with long-baseline radio interferometers, revealing the presence of outflows. It is expected that at very low frequencies the synchrotron radio emission covers larger angular scales than has been reported up to now. Here we present preliminary results of the first deep radio observations of the gamma-ray binary LS I +61 303 with LOFAR, which is sensitive to extended structures on arcsecond to arcminute scales. [ABSTRACT FROM AUTHOR]

Gamma-ray binary systems are still a sparsely populated source class. Although the individual gamma-ray binaries share some common features, it is not possible to explain their emission mechanisms in a common framework yet. We present the highlights from our MAGIC observations of the best studied northern binary system, LS I +61°303, revealing its complex emission behavior. Furthermore we present observations of the binary HESS J0632+057 which MAGIC observed during an X-ray outburst in 2011. We compare these binary systems, and discuss common features as well as possible differences between them. [ABSTRACT FROM AUTHOR]

This presentation concerns the study of the movement of Earth-type planets orbiting stars that form binary systems. It is well known that, in accordance with the restricted three-body problem, zones of stability exist either close to the stars or far from both of them, with S-type or P-type orbits, respectively. We consider the different initial conditions for eight cases (4 of the S-type and 4 of the P-type) and we study the variation of the orbital elements during a moderate time interval, for both the orbit of the binary as well as for the Earth-type planet. Analyzing the different perturbations, we arrive at the conclusion that in many cases, the existence of Earth-type planets within the zone of habitability is perfectly possible. Only in those cases in which the pair is formed by red dwarfs with P-type orbits, there is a limitation due to the fact that the period of the double star is very small. We also comment on the possibility that Earth-type exosatellites may exist around giant planets, although it has not been possible to detect the presence of these yet. [ABSTRACT FROM AUTHOR]

Orbital period variations of two contact binaries DF Hya and WZ And are analyzed with the least-squares method by using all available minima times. It is shown that the period variations of these systems are due mainly to the Light-Time Effect (LITE) due originates from gravitational influence of a third body. New LITE elements such as, orbital periods and minimum masses of possibility third bodies are given. [ABSTRACT FROM AUTHOR]

The long period eclipsing binaries are the best tools to determine accurate spectroscopic elements of the orbit. Unfortu-nately, the number of well-studied long period eclipsing binaries (LPEBs) is quite small due to necessity of long term observing programmes with big telescopes together with relatively high resolution spectrographs. At the UBT60 telescope of Akdeniz University located in TÜBİTAK National Observatory, we started a programme to study LPEBs spectroscopically. In this study, we present spectroscopic orbital parameters of some selected long period early-type eclipsing binary stars. [ABSTRACT FROM AUTHOR]

In this study we investigate the evolution of binary systems towards low mass x-ray binaries and high mass x-ray binaries using Eggleton's binary star evolution code. [ABSTRACT FROM AUTHOR]

In this study, angular momentum loss via gravitational radiation in double degenerate binary (DDB)systems (NS + NS, NS + WD, WD + WD, and AM CVn) is studied. Energy loss by gravitational waves has been estimated for each type of systems. [ABSTRACT FROM AUTHOR]