Related papers: Light Curve Analysis of Hipparcos Data for the Mas…

W UMa type binaries have two defining characteristics. These are (i) the effective temperatures of both components are very similar, and (ii) the secondary (currently less massive) component is overluminous for its current mass. We consider…

The accuracy of absolute parameters' estimation in contact binary systems is important for investigating their evolution and solving some challenges. The Gaia DR3 parallax is one of the methods used for estimating the absolute parameters,…

In this study, we determined the physical parameters of W UMa type contact binaries and its stability of mass transfer with different stellar mass ranges over a broad space by applying the basic dynamical evolution equations of the W UMa…

Multi-band photometric observations of eleven totally eclipsing contact binaries were carried out. Applying the Wilson-Devinney program, photometric solutions were obtained. There are two W-subtype systems, which are CRTS J133031.1+161202…

Double-lined spectroscopic orbital elements have recently been found for the central binary in the massive triple, delta Orionis A based on radial velocities from cross-correlation techniques applied to IUE high dispersion spectra and He I…

Multi-band photometric analysis of the contact binary V717 Andromedae (V717 And) is presented. The system is found to be an extreme low mass ratio system (q = 0.197) with high inclination (i = 84.5 deg), moderate degree of contact (27%) and…

In this study, we present photometric and spectroscopic variations of the extremely small mass ratio ($q\simeq 0.1$) late-type contact binary system \astrobj{V1191 Cyg}. The parameters for the hot and cooler companions have been determined…

We presented the first photometric analysis of the V1961 Cyg and V0890 Lyr binary systems. We observed and analyzed these systems at an observatory in France as part of the Binary Systems of South and North (BSN) Project. We extracted and…

We selected mass-transferring binary candidates from the catalog of Kepler eclipsing binary stars and investigated the dependence of the mass-transfer rate on several astrophysical quantities, including orbital period, semi-major axis, mass…

We performed new photometric observations for two contact binaries (i.e., CRTS J025408.1+265957 and CRTS J012111.1+272933), which were observed by the 1.0-m telescope at Xingjiang Astronomical Observatory. From our light curves and several…

We report on high-speed eclipse photometry of the dwarf nova V2051 Oph while it was in a low brightness state, at B ~ 16.2 mag. In comparison to the average IUE spectra, the ultraviolet continuum and emission lines appear reduced by factors…

When observing the transiting extrasolar planets, we discovered a new W UMa type binary GSC 03553-00845. Following observation was carried out using the 1m telescope at Weihai Observatory of Shandong University. Complete BVR light curves…

In the first paper of this series, we presented a detailed high-resolution spectroscopic study of CPD - 41degr7742, deriving for the first time an orbital solution for both components of the system. In this second paper, we focus on the…

This study examines the period variation of the eclipsing binary system KR Cyg, a near-contact binary characterized by its short orbital period and significant stellar interactions. The precise orbital parameters of the system have been…

We present new constraints on the system parameters of the SW Sextantis star DW Ursae Majoris, based on ultraviolet (UV) eclipse observations with the Hubble Space Telescope. Our data were obtained during a low state of the system, in which…

Spectroscopic and eclipsing binary systems offer the best means for determining accurate physical properties of stars, including their masses and radii. The data available for low-mass stars have yielded firm evidence that stellar structure…

High resolution spectroscopic observations of AW UMa, obtained on three consecutive nights with the median time resolution of 2.1 minutes, have been analyzed using the Broadening Functions method in the spectral window Doppler images of the…

The contact binary AW UMa has an extreme mass ratio, with the more massive component (the current primary) close to the main sequence, while the low mass star at q ~ 0.1 (the current secondary) has a much larger radius than a main sequence…

By analyzing two sets of complete $BVR_cI_c$ light curves of V342 UMa and three sets of complete $BVR_cI_c$ light curves of V509 Cam, we determined that the two systems are both W-subtype contact binaries and that V342 UMa shows a shallow…

The photometric analysis and spectroscopic study of the long period low mass ratio deep contact binary KN Per were executed. The light curves of BV(RI)$_c$-band were from the Ningbo Bureau of Education and Xinjiang Observatory Telescope…