A photometric study of the eclipsing binary V 1073 Cygni

Photoelectric observations of the eclipsing binary V 1073 Cyg have been carried out inB andV colours at the Ege University Observatory. The light curves were analyzed with the Wilson-Devinney approach. A period study reveals that the orbital period of the system is decreasing at the rate of (3.21 ± 0.17) second per century.     

A photometric study of the short-period eclipsing binary BW Eridani

UBV observations of the short-period eclipsing binary BW Eri are reported and analyzed. The photometric parameters are determined. BW Eri is a detached or semidetached system.     

The multi-band CCD photometric investigation of short-period eclipsing binary V1044 Her

We present new CCD photometric observations of V1044 Her obtained on May 22, 23 and 24, 2015. From our data, we derived five new light curve minimum times. Combining our new results with previously available CCD light minimum times, we derived an updated ephemeris and discovered that the period of this binary system exhibits an oscillation. The cyclic variation may be caused by the light-time effect via the presence of a third body or magnetic activity cycle. We calculated the corresponding period of the third body to be 14.1 ± 1.4 years or magnetic cycle to be 12.2 ± 0.7 years. We analyzed our new asymmetric light curves to obtain photometric solutions and starspot parameters using the Wilson and Devinney program. The final results show that V1044 Her is a contact binary system with a degree of contact factor f = 3.220( ± 0.002)%.     

First photometric study of the eclipsing binary PS Persei

CCD photometric observations of the eclipsing binary PS Persei (PS Per) were obtained on two consecutive days in 2009.The 2003 version of the WilsonDevinney code was used to analyze the first complete light curves in the V and R bands.It is found that PS Per is a short-period Algol-type binary with the less massive component completely filling its inner critical Roche lobe.The mass ratio of q=0.518 and the orbital inclination of i=89.86° are obtained.In addition,based on all available times of primary light...     

Comprehensive photometric study of the eclipsing binary AW UMa

Due to its extreme mass ratio, the system AW UMa is considered as one of the most interesting contact binaries. In the present paper, a total of 1289 observations in VRI band were carried out from on 2006 March 7, 8, and 9 at Piszkesteto, Mountain Station of the Konkoly observatory (Hungary). VRI light curves were constructed and a photometric solution of these light curves was obtained by means of Willson-Devinney code. The results show that the primary component is more massive and hotter than the primary component by ～140 K. A secular period decrease with a rate dP/dE=2.436×10^?10 day/cycle was detected. Based on the physical parameters of the system, we investigate the evolutionary state of the components. The primary component is above the zero age main sequence (ZAMS) track, while the secondary component has a larger radius and luminosity than expected from its ZAMS mass.     

A multicolor photometric study of the neglected eclipsing binary FT Ursae Majoris

The multicolor photometric observations of the neglected eclipsing binary FT Ursae Majoris (FT UMa) were obtained in 2010. The 2003 version of the Wilson-Devinney code was used to analyze the light curves in the B, V and R bands simultaneously. Based on the spectroscopic mass ratio q = 0.984 published by Pribulla et al., it is found that FT UMa is an evolved contact binary with a contact degree of 15.3%. The low amplitude of light variations, ～ 0.15 mag, arises mainly from a moderately low inclination angle...     

A photometric and spectroscopic study of the short-period eclipsing binary BV Eridani

UBV observations of the short-period eclipsing binary BV Eri are reported and analyzed. The radial velocity curve is given. The system shows a light curve distortion, making an analysis difficult. The secondary fills its critical Roche lobe. The system seems to be in an interesting evolutionary.     

A comprehensive photometric study of the Algol-type eclipsing binary: BG Pegasi

This study presents new photometric observations of classical Algol type binary BG Peg with a δ Scuti component. The light curve modeling was provided with the physical parameters of the component stars in the BG Peg system for the first time. After modeling light curves in B and V filters, the eclipse and proximity effects were removed from the light curve to analyze intrinsic variations caused by the hotter component of the system. Frequency analysis of the residuals light represents the multi-mode pulsation of the more massive component of the BG Peg system at periods of 0.039 and 0.047 days. Two frequencies could be associated with non-radial (l = 2) modes. The total amplitude of the pulsational variability in the V light curve was found to be about 0.045 mag. The long-term orbital period variation of the system was also investigated for the first time. The O–C analysis indicates periodic variation superimposed on a downward parabola. The secular period variation means that the orbital period of the system is decreasing at a rate of ?5.5 seconds per century, probably due to the magnetic activity of the cooler component. The tilted sinusoidal O–C variation may be caused by the gravitational effect of an unseen component around the system.     

A photometric analysis of the eclipsing binary system X Pictoris

X Pictoris is an eclipsing binary with a period of 0^d.8619. The analysis presented in this paper is based on previously unreduced observations inUBV made by Somerville in 1961–1962. Orbital elements are obtained using the Wood model. A consistent geometry is determined, and the mass-ratio is found to be about 0.6. Although the light curves of X Pic resemble those of a classical Algol-type binary, the system is shown to be detached with the primary component a normal Main-Sequence star and the secondary an undersize subgiant. There is some uncertainty as to the spectral classes of the components, but they almost certainly fall into the range A2V to F0V for the primary and G6IV to K2IV for the secondary. Although discovered in 1907, X Pic has been until now a virtually unknown binary, and this paper presents the first reliable ephemeris and definitive photometric analysis to be made of this system.     

The first photometric study of W UMa eclipsing binary OQ Dra

The present study is an analysis of V-band CCD observations of new W UMa contact binary OQ Dra. To carry out the analysis, Primary and secondary minimum were obtained and new epoch was calculated. The computed period of system was 0.33967 day. Light curve analysis was performed using Binary Maker 3 and PHOEBE that uses the latest Wilson–Devinney code. We obtained photometric mass ratio of q_ptm = 0.55.O’Connell effect also was seen in the fitted model. Finally, the best model was achieved by introducing 2 spots on each component.     

The detached eclipsing binary TX Her revisited

This paper presents new CCD Bessell BVRI light curves and photometric analysis of the Algol-type binary star TX Her. The CCD observations were carried out at Çanakkale Onsekiz Mart University Observatory in 2010. New BVRI light curves from this study and radial velocity curves from Popper (1970) were solved simultaneously using modern light and radial velocity curves synthesis methods. The general results show that TX Her is a well-detached eclipsing binary, however, both component stars fill at least half of their Roche lobes. A significant third light contribution to the total light of the system could not be determined. Using O–C residuals formed by the updated minima times, an orbital period study of the system was performed. It was confirmed that the tilted sinusoidal O–C variation corresponds to an apparent period variation caused by the light travel time effect due to an unseen third body. The following absolute parameters of the components were derived: M₁ = 1.62 ± 0.04 M_⊙, M₂ = 1.45 ± 0.03 M_⊙, R₁ = 1.69 ± 0.03 R_⊙, R₂ = 1.43 ± 0.03 R_⊙, L₁ = 8.21 ± 0.90 L_⊙ and L₂ = 3.64 ± 0.60 L_⊙. The distance to TX Her was calculated as 155 ± 10 pc, taking into account interstellar extinction. The position of the components of TX Her in the HR diagram are also discussed. The components are young stars with an age of ～500 Myr.     

The first photometric study of semi-detached eclipsing binary V504 Cyg

In this paper, we analyze photometry of V504 Cyg semi-detached binary system. For this purpose, after taking the photometric data, primary and secondary minimum and new epoch were calculated. The period of system is found to be 0.3516916 day. Analysis of light curve was performed by PHOEBE software which uses last version of Wilson–Devinney code. 3D model of the system is worked out using Binary Maker software. The O’Connell effect in the light curve is observed and an accurate model of this system is presented by introducing four spots on the components.     

A new photometric analysis of the eclipsing binary system ST Carinae

ST Carinae is an eclipsing binary with a period of 0 _. ^d 90165 which is believed to consist of an A0V primary and a secondary of type F5-8IV. About 900 observations inUBV, made by Somerville in 1963 but unreduced at that time, are presented. The Wood model is used to obtain orbital elements, and four different solutions of the light curves are presented. These are also computed with the solutions obtained by previous investigators of this system. The solutions indicate a reasonably consistent geometry, but there is still substantial uncertainty with regard to the mass-ratio and dynamical status of ST Car. The possibility exists that ST Car is in the initial and rapid stage of mass exchange in which the primary component fills its Roche lobe and is losing mass to its companion. The two components of ST Car appear to be of normal dimensions, but additional work is needed to clarify the exact status of this system.     

Revised photometric elements of the eclipsing binary TW Dra

The photoelectric light curves of TW Dra obtained by Baglow (1952) and by Walter (1978) have been re-analysed by means of Wood's (1972) model in order to obtain accurate photometric elements. Significantly different elements have resulted from the two sets of observations, but more confidence can be given to the elements deduced from Walter's (1978) data. Radii and luminosities have been computed with the aid of Popper's (1978) new values for masses.TW Dra is confirmed to be a typical sd-system, having a distinctly oversized and overluminous secondary. Interestingly, the primary appears to be slightly more luminous than expected for a Main-Sequences star, in agreement with theoretical predictions for present primaries of massexchange binaries systems.     

Revised photometric elements of the eclipsing binary DS and

With the aid of WOOD 's (1972) model we have reanalyzed MAGALASHVILI and KUMISHVILI 's (1978) UBV light curves of the eclipsing binary DS And. Our photometric elements considerably differ from the previous ones and show that DS And can be related to the contact systems.     

Revised photometric elements of the eclipsing binary AI Cru

Using Wood's (1972) model we have re-analyzed the photoelectric light curve of the eclipsing binary AI Cru, published and unsatisfactorily discussed by Ollongren (1956), in order to obtain reliable photometric elements. Our photometric solution differs considerably from Ollongren's (1956). For our photometric mass ratio,q=0.8, both components, though detached from their Roche lobes, are fairly close to a contact configuration.AI Cru, composed of a brighter and larger B5 primary and a fainter and smaller (around B9.5) secondary, is probably not a normal Main Sequence system, since the ratios of the secondary's mass and radius over the primary's turn out to be larger than expected for main sequence stars of the same spectral types.