Related papers: The eclipsing LMC star OGLE05155332--6925581: a cl…
In this paper we analyzed the light curve of the object KIC~3832716 observed during Kepler K1 mission. We showed that this previously known eclipsing binary is in fact quadruple system, in double eclipsing binary configuration on a long…
Doppler measurements of two G-type main-sequence stars, HD210277 and HD168443, reveal Keplerian variations that imply the presence of companions with masses (M sin i) of 1.28 and 5.04 M_Jup and orbital periods of 437 d and 58 d,…
We present an updated collection of eclipsing and ellipsoidal binary systems in the Large and Small Magellanic Clouds (LMC and SMC), as observed by the Optical Gravitational Lensing Experiment (OGLE) survey. The catalog comprises a total of…
Photometric observations of the supersoft X-ray source 1E 0035.4-7230 obtained during two years reveal that the very blue optical counterpart (V (maximum)=20.2, B-V=-0.15, U-B=-1.06) undergoes nearly sinusoidal variations with a period of…
We report on observations of the eclipsing binary 2MASS 19090585+4911585 with the 25 cm auxiliary telescope of the University Observatory Jena. We show that a nearby brighter star (2MASS 19090783+4912085) was previously misclassified as the…
We have obtained extensive high-quality spectroscopic observations of the OGLE-LMC-CEP-1718 eclipsing binary system in the Large Magellanic Cloud which Soszynski et al. (2008) had identified as a candidate system for containing two…
We report the discovery of 1RXH J082623.6-505741, a 10.4 hr orbital period compact binary. Modeling extensive optical photometry and spectroscopy reveals a $\sim 0.4 M_{\odot}$ K-type secondary transferring mass through a low-state…
Detached eclipsing binaries (DEBs) allow for the possibility of precise characterization of its stellar components. They offer a unique opportunity to derive their physical parameters in a near-model-independent way for a number of systems…
HD 163296 is a Herbig Ae star that underwent a dramatic $\sim$0.8 magnitude drop in brightness in the V photometric band in 2001 and a brightening in the near-IR in 2002. Because the star possesses Herbig-Haro objects travelling in…
We report the discovery of a new subclass of double-mode RR Lyrae stars in the Large and Small Magellanic Clouds. The sample of 22 pulsating stars have been extracted from the latest edition of the OGLE collection of RR Lyrae variables in…
A thorough analysis of the OGLE-II time-series photometry of the Large Magellanic Cloud bar supplemented by similar data from the MACHO database led us to the discovery of three Beta Cephei-type stars. These are the first known…
Our goal is to determine, with high accuracy, the physical and orbital parameters of two double-lined eclipsing binary systems, where the components are two giant stars. We also aim to study the evolutionary status of the binaries, to…
One of the most interesting results from the OGLE-III study of the LMC Cepheids is the large number of objects that pulsate simultaneously in the first and second overtone (denoted 1O/2O). Double-mode Cepheids yield important constraint on…
We report on the preliminary results of a three-year monitoring campaign of Galactic and Magellanic LBVs with both moderate and high resolution spectroscopy. We have collected more than 500 moderate-resolution spectra of 20 stars in the red…
We used the OGLE-II and OGLE-III photometry of red giants in the Large Magellanic Cloud to select and study objects revealing ellipsoidal variability. We detected 1546 candidates for long period ellipsoidal variables and 121 eclipsing…
We report the discovery of CoRoT 102980178 (R.A.= 06:50:12.10, Dec.= -02:41:21.8, J2000) an Algol-type eclipsing binary system with a pulsating component (oEA). It was identified using a publicly available 55 day long monochromatic…
We present a spectroscopic and photometric study of the Double Period Variable HD170582. Based on the study of the ASAS V-band light curve we determine an improved orbital period of 16.87177 $\pm$ 0.02084 days and a long period of 587 days.…
We present both binarity and pulsation of KIC 6220497 from the {\it Kepler} observations. The light curve synthesis shows that the eclipsing system is a semi-detached Algol with parameters of $q$ = 0.243$\pm$0.001, $i$ = 77.3$\pm$0.3 deg,…
To confirm faint Be/X-ray binary candidates from the XMM-Newton survey of the Small Magellanic Cloud, we searched for X-ray outbursts in archival ROSAT observations. We found that RXJ0123.4-7321 was much brighter when detected with ROSAT…
We have analysed photometric data for the first overtone Cepheids in the Magellanic Clouds from the OGLE collection. In more than 500 stars, we have detected additional variability with periods shorter than the first overtone period and…