Related papers: Testing the planetary models of HU Aquarii
We report on a ~37-ks XMM-Newton observation of the intermediate polar FO Aquarii, presenting X-ray and UV data from the EPIC and OM cameras. We find that the system has changed from its previously reported state of disc-overflow accretion…
The results of the spectral observations of a unique eclipsing system {\epsilon} Aurigae obtained during the recent eclipse are presented. We traced the spectral lines variations at different eclipse phases. The part of these changes is the…
Multiband CCD photometric observations of SZ Her were obtained between 2008 February and May. The light curve was completely covered and indicated a significant temperature difference between both components. The light-curve synthesis…
We present the discovery of 11 new double degenerate systems containing extremely low-mass white dwarfs (ELM WDs). Our radial velocity observations confirm that all of the targets have orbital periods $\leq$ 1 day. We perform spectroscopic…
We have performed extensive simulations to explore the possibility of detecting eclipses and transits of close, sub-stellar and planetary companions to white dwarfs in WASP light-curves. Our simulations cover companions $\sim0.3\Re<{\rm…
Binary radio pulsar system J0737-3039 provides an exceptional opportunity to study innermost structure of pulsar magnetospheres due to very tight orbit, favorable directions of pulsars' rotation and magnetic axes and extremely fortuitous…
We present the discovery of the eclipsing double white dwarf (WD) binary WDJ 022558.21-692025.38 that has an orbital period of 47.19 min. Following identification with the Transiting Exoplanet Survey Satellite, we obtained time-series…
We used photometric data from the WASP (Wide-Angle Search for Planets) survey to explore the possibility of detecting eclipses and transit signals of brown dwarfs, gas giants and terrestrial companions in close orbit around white dwarfs. We…
We present high-speed ULTRACAM and SOFI photometry and X-shooter spectroscopy of the recently discovered 94 minute orbital period eclipsing white dwarf / main-sequence binary SDSS J085746.18+034255.3 (CSS 03170) and use these observations…
We study the timing and spectral properties of the intermediate polar MU Camelopardalis (1RXS J062518.2+733433) to determine the accretion modes and the accretion geometry from multi-wavelength, multi-epoch observational data. Light curves…
Optical time series photometry of the short period magnetic white dwarf + probable brown dwarf binary SDSS 121209.31+013627.7 reveals pulse-like variability in all bands from i' to u', peaking at u'. These modulations are most likely due to…
We present three new eclipsing white-dwarf / M-dwarf binary systems discovered during a search for transiting planets around M-dwarfs. Unlike most known eclipsing systems of this type, the optical and infrared emission is dominated by the…
Two Chandra observations of the R Aqr symbiotic binary system taken 3.3 years apart show dramatic changes in the X-ray morphology and spectral characteristics in the inner 500 AU of this system. The morphology of the soft X-ray emission has…
Eclipsing binaries are important tools for studying stellar evolution and stellar interiors. Their accurate fundamental parameters are used to test evolutionary models, and systems showing apsidal motion can also be used to test the model's…
A nonlinear nature of the binary ephemeris of Cygnus X-3 indicates either a change in the orbital period or an apsidal motion of the orbit. We have made extended observations of Cygnus X-3 with the Pointed Proportional Counters (PPCs) of…
Tidal interactions are one of the primary drivers of orbital evolution for massive planets with short orbital periods. Tidal dissipation within host stars can cause the orbits of such planets to decay. However, the mechanisms of tidal…
A series of 353 red electronic spectra obtained between 1994 and 2010, and of 171 UBV photometric observations of the 2010 eclipse, were analyzed in an effort to better understand the eclipsing binary eps Aur. The main results follow. (1)…
We present the first high time resolution light curves for six eclipses of the magnetic cataclysmic variable EP Dra, taken using the superconducting tunnel junction imager S-Cam2. The system shows a varying eclipse profile between…
LX Ser is a deeply eclipsing cataclysmic variable with an orbital period of $0.^d 1584325$. Sixty two new eclipse times were determined by our observations and the AAVSO International Data base. Combining all available eclipse times, we…
A double planet system or planet binary undergoes eclipses that modify the reflective light curve. In the time domain, the eclipse events are fast and weak. This would make their signal difficult to find and recognize in the phase light…