Related papers: A study of contact binaries with large temperature…
Binary systems play a crucial role in massive star evolution. Systems composed of B-type and O-type stars are of particular interest due to their potential to lead to very energetic phenomena or the merging of exotic compact objects. We aim…
We present a study of the superconducting energy gap performed with point contact spectroscopy in a single crystal of the superconductor Zr0:97V0:03B2. We determined the size and evolution with temperature of the energy gap, the transition…
The first photometric analysis of V811 Cep was carried out. The first complete light curves of V, R and I bands are given. The analysis was carried out by Wilson-Devinney (W-D) program, and the results show that V811 Cep is a median-contact…
New V photoelectric observations of the eclipsing system YY CMi, obtained at La Silla, Chile, and Merate Observatory, Italy, are presented. New times of minima and ephemeris based on our observations are also given. The V light curve was…
This paper selected eight totally eclipsing contact binaries for photometric and spectroscopic studies, spectral data were analyzed by ULySS, and photometric data were analyzed using PHOEBE through MCMC sampling. We used two methods to…
The origin of rapid rotation in massive stars remains debated, although binary interactions are now often advocated as a cause. However, the broad and shallow lines in the spectra of fast rotators make direct detection of binarity…
Colliding wind binaries (CWBs) have been considered as a possible high energy $\gamma$-ray sources for some time, however no system other than $\eta$ Car has been detected. In the paper a sample of seven CWBs (WR 11, WR 70, WR 137, WR 140,…
The physical properties of the Zr$_5$Pt$_3$ compound with interstitial carbon in hexagonal D8$_8$-structure was investigated. A set of macroscopic measurements reveal a bulk superconducting at approximately 7 K for Zr$_5$Pt$_3$C$_{0.3}$…
Context. Despite the fact that VW Cephei is one of the well-studied contact binaries in the literature, there is no fully consistent model available that can explain every observed property of this system. Aims. Our motivation is to obtain…
The article presents the results of the analysis of optical light curves of the massive binary system WR 20a (WN 6ha + WN 6ha). The analysis was performed with the binary system model, extending the standard Roche model for the case when…
Detailed studies of hot subdwarf B stars with red dwarf or brown dwarf companions can shed light on the effects of binarity on late stellar evolution. Such systems exhibit a strong, quasi-sinusoidal reflection effect due to irradiation of…
Far-ultraviolet (FUV) radiation is a driving source of photochemistry in planetary atmospheres. Proper interpretation of atmospheric observations requires a full understanding of the radiation environment that a planet is exposed to. Using…
AH Cep and CW Cep are both early B-type binaries with short orbital periods of 1.8~d and 2.7~d, respectively. All four components are B0.5V types. The binaries are also double-lined spectroscopic and eclipsing. Consequently, solutions for…
We present the first detailed multiband (BVR_cI_c and TESS) photometric analysis of the short-period binary EZ Oct. This study combines ground-based observations conducted at a Southern Hemisphere observatory in Argentina with data from the…
A complete astrophysical and dynamical study of the close visual binary system (CVBS) (A7V + F0V), Finsen 350, is presented. Beginning with the entire observational spectral energy distribution (SED) and the magnitude difference between the…
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…
Light curve modeling for the newly discovered system 1SWASP J092328.76+435044 was carried out by using a new BVR complete light curves. A spotted model was applied to treat the asymmetry of the light curves. The output model was obtained by…
The period distribution of contact binaries exhibits a very sharp short period cut-off at 0.22 days. In order to provide valuable information on this short period limit, we observed ten totally eclipsing contact binaries with orbital…
We present the first detailed investigation of six eclipsing binary systems in the TESS field. The TESS light curves of the targets are analysed by determining the initial effective temperatures via SED fits. The absolute parameters are…
Optical high-resolution spectra of the R Coronae Borealis star V CrA at light maximum and during minimum light arediscussed. Abundance analysis confirms previous results showing that V CrA has the composition of the small subclass of R…