The eclipsing binary WX Eridani

The Algol type eclipsing binary WX Eridani was observed on 21 nights with the 48-inch telescope of the Japal-Rangapur Observatory during 1973–74 and 1974–75 seasons in UBV colors. An improved period ofP=0^d.82327038 was obtained from the analysis of the times of five primary minima. Standstills between phase angles 50–80°, 100–130°, 230–260° and 280–310° were present in the light curves. The analysis of the light curves indicated the eclipses to be grazing with the primary a transit and the secondary an occultation. Elements derived from the solution of the light curve using Russell-Merrill method are given. From the comparison of the fractional radii with Roche lobes, it is concluded that none of the components has filled its respective Roche lobe. The spectral type of the primary component is estimated to be F3 and it is found to be a -scuti type variable pulsating with two periods equal to one-fifth and one-sixth of the orbital period.     

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.     

UBV photometry of the eclipsing binary RZ Eridani

U, B, andV observations of RZ Eri have been reported. Colours of comparison stars BD-10°994, BD-10°996 and of the variable RZ Eri have been presented. The observations of RZ Eri do not indicate the distortion wave in the light curve beyond observational scatter.     

BV observations of the eclipsing binary WX Eridani

Photoelectric observations of WX Eridani inB andV filters have been discussed. The maximum magnitudes of the system areB=9 ^m .70 andV=9 ^m .46. TheB-V colours of the components are 0 ^m .16 and 0 ^m .80 for the primary and the secondary, respectively, while their spectral types are A5+K0. The period has been found to be constant and its revised value is 0^d.823 270 76.     

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.     

Photoelectric study of the eclipsing system CD Eridani

Limiting photometric solutions for the system CD Eri inB andV filters have been obtained. The secondary minimum was found to be absent.     

The almost contact system RU Eridani

TheV andB light curves of the eclipsing binary RU Eridani, published by Sarma and Sanwal (1981), have been analysed by means of the Wilson and Devinney (1971) method, in order to obtain a solution based on the Roche model, as distinct from the Russell and Merrill model, used by Sarma and Sanwal. The system turns out to consist of an evolved K1 secondary which appears to fill the lobe, capable of containing its mass, and of an F0 V primary, which seems almost to fill its own. An estimate of the absolute elements of RU Eri has been made, on the assumption that the primary has a mass corresponding to its spectral type according to Allen (1973).     

Photometric study of the eclipsing binary IU Aurigae

New UBV photometric observations of IU Aur were made at McDonald Observatory in December 1984 and January 1985, showing that the eclipse depth had kept on increasing and the light minimum time had shown periodic changes. Orbital elements were obtained using the Wilson-Devinney method. The inclination is now close to 90°. The continuous variation of inclination over the last few decades suggests the presence of a third body. Absolute parameters of IU Aur were calculated with the help of Mammano's spectral data.     

A study of the eclipsing binary XX Cas

UBV photometry of the eclipsing binary system XX Cas has been presented. Primary eclipse appears to be a total occultation rather than a partial transit (Pierce, 1938). A slightly improved period of 3^d.0671708 has been obtained, and the colour of the system discussed.     

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...     

Photometric study of the algol-type eclipsing binary EU hydrae

In this paper, we give theBV photoelectric light curves of the Algol-type eclipsing binary EU Hydrae. We have analysed its period by means of the times of minima determined from this observation and the times of minima which other observers published. The period was found to gradually decrease with a change rate dP/dE = -3 _. ^d 29 × 10^–10. The obtained light curves have been solved using Wilson-Devinney's synthetic light-curve program. The results demonstrate that EU Hydrae is a detached system, the secondary component fills the Roche-lobe, its mass ratio is 0.205. EU Hya may evolve to be a semidetached system in which the secondary component fills the Roche-lobe.     

Spectrographic study of the eclipsing binary system SZ Camelopardalis

Thirteen high-dispersion spectrographs of the eclipsing binary star SZ Cam have been studied with a view of determining more accurate information on: (i) the spectral type and luminosity classifications, (ii) absolute parameters for the component stars, (iii) the stellar environment of SZ Cam. The main results in these categories are as follows: (i) O9.5 Vnk, (ii)m _g=19±2M _⊙,m _s=6.5±1M _⊙;r _g=9.7±3.6R _⊙,r _s=4.8±1.7R _⊙;T _e～30000 K,T _e～23000 K; (iii) there is a local concentration of absorbing material which may reach a density of 2M _⊙ pc^?3, and the distance of the star is found to be 600±150 pc. The determined overluminosity of the secondary star and the local concentration of absorbing material are two topics which provide the basis for a discussion section.     

Spectroscopic study of the eclipsing binary V 367 Cygni

Seventeen coudé spectrograms (dispersion 20 A mm^–1) of the Lyrae-type eclipsing binary V 367 Cygni (P=18.6 d) have been studied. The observations were made at the Haute Provence Observatory during a period of almost two years (May 1973–March 1975). An anomalous behavior for the radial velocities of the spectrograms taken during one cycle (406) was observed; it is suggested that gas eruption under form of prominences may explain it. The spectrum is dominated by shell lines very similar to those present in the spectrum of the supergiant A9 Ia Aurigae. The underlying stellar spectrum is classified as A5 I on the basis of the intensity of the sole clearly visible stellar line, 4481 MgII, of the wings of the stellar Balmer lines, and an estimate of the intensity of the stellarK line. The radial velocity curves for the shell lines of CaII, HI, metallic ions and neutral iron, as well as the phase dependence of the microturbulence, indicate stratification in the shell.     

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 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 eclipsing binary 68 u Her

The aim of this paper is to present and study the light curves (B andV) of the eclipsing binary 68 u Her from the photometric observations made at Al-Battani Observatory.New photometric elements have been obtained by a Fourier analysis of the light changes in the frequency-domain.