Related papers: Ellipsoidal effect in the symbiotic star YY Her

We analyze the historical light curve of the symbiotic star YY Her, from 1890 up to December 2005. A secular declining trend is detected, at a rate of ~.01 magn in 1000 d, suggesting that the system could belong to the sub-class of…

We present and analyze quiescent UBVRI light curves of the classical symbiotic binary YY Her. We show that the secondary minimum, which is clearly visible only in the quiescent VRI light curves, is due to ellipsoidal variability of the red…

One of fundamental questions in relation to symbiotic binaries is the process of mass transfer - Roche lobe overflow or stellar wind - and possibility of an accretion disc formation. The presence of secondary minima in the quiescent light…

We have followed up on the hot-type classical symbiotic outburst reported in YY Her using the Himalayan Chandra telescope. The outburst coincides with the secondary minima of the system. Approximately 12 similar brightening events have been…

Although comparatively bright, the cataclysmic variable GY Hya has not attracted much attention in the past. As part of a project to better characterize such systems photometrically, we observed light curves in white light, each spanning…

Several studies have already considered the influence of tides on the evolution of systems composed of a star and a close-in companion to tentatively explain different observations such as the spin-up of some stars with hot Jupiters, the…

We study the perturbations of a relatively close third star on a tidally distorted eccentric eclipsing binary. We consider both the observational consequences of the variations of the orbital elements and the interactions of the stellar…

As the generalization of gravitational effects on the point mass systems, we want to study the tidal effect exerted on an extended stellar system using spherical and axisymmetric elliptical models. Considering the Isochrone and Plummer…

This paper summarizes our recent results on tidal interaction in high mass X-ray binaries and symbiotic stars. We demonstrate that the giant in symbiotic stars with orbital periods <1200 d are co-rotating (synchronized). The symbiotics MWC…

MACHO project photometry shows the candidate Symbiotic Star V5485 Sagittarii's red giant component has a photometric orbital period of 270 days as evidenced by ellipsoidal variation of the lightcurve.

We investigate two possible effects of the tidal field induced by a spherical cluster on its elliptical galaxy members: the modification of the ellipticity of a spherical galaxy and the isophotal alignment in the cluster radial direction of…

Hundreds of substellar companions to solar-type stars will be discovered with the Kepler satellite. Kepler's extreme photometric precision gives access to low-amplitude stellar variability contributed by a variety of physical processes. We…

I introduce fundamental types of variations observed in the light curves (LC) of symbiotic stars: the orbitally-related wave-like modulation during quiescent phases, eclipses during active phases and apparent orbital changes indicated…

The geometry and morphology of symbiotic stars are conducive to exhibit a variety of scattering phenomena. The prominent among them is the Raman scattering of O VI doublet $\lambda \lambda$ 1032,1038 angstrom, which often show strongly…

We present results of period analysis of ASAS, MACHO and OGLE light curves of 79 symbiotic stars classified as S and D'-type. The light curves of 58 objects show variations with the orbital period. In case of 34 objects, orbital periods are…

We present an analysis of the early Kepler observations of the previously discovered transiting planet HAT-P-7b. The light curve shows the transit of the star, the occultation of the planet, and the orbit phase-dependent light from the…

We present optical and infrared observations taken with the Very Large Telescope of the eclipsing binary pulsar system PSR B1718-19. The candidate companion of the pulsar, identified earlier in Hubble Space Telescope observations, has been…

V503 Her was previously proposed as an eclipsing symbiotic candidate based on photometric behavior and spectroscopic appearance indicating the composite optical spectrum. To investigate its nature, we analyzed long-term photometric…

Planets orbiting very close to their host stars have been found, some of them on the verge of tidal disruption. The ellipsoidal shape of these planets can significantly differ from a sphere, which modifies the transit light curves. Here we…

From its discovery, the WASP-18 system with its massive transiting planet on a tight orbit was identified as a unique laboratory for studies on tidal planet-star interactions. In an analysis of Doppler data, which include five new…