The Eclipsing Binary WX Eridani

1979 ◽  
Vol 46 ◽  
pp. 385
Author(s):  
M.B.K. Sarma ◽  
K.D. Abhankar
Keyword(s):  
Light Curve ◽  
Spectral Type ◽  
Orbital Period ◽  
Primary Component ◽  
Light Curves ◽  
Absorption Feature ◽  
Primary Star ◽  
Eclipsing Binary ◽  
The Times ◽  
Phase Angles

AbstractThe Algol-type eclipsing binary WX Eridani was observed on 21 nights on the 48-inch telescope of the Japal-Rangapur Observatory during 1973-75 in B and V colours. An improved period of P = 0.82327038 days was obtained from the analysis of the times of five primary minima. An absorption feature between phase angles 50-80, 100-130, 230-260 and 280-310 was present in the light curves. The analysis of the light curves indicated the eclipses to be grazing with primary to be transit and secondary, an occultation. Elements derived from the solution of the light curve using Russel-Merrill method are given. From comparison of the fractional radii with Roche lobes, it is concluded that none of the components have filled their respective lobes but the primary star seems to be evolving. The spectral type of the primary component was estimated to be F3 and is found to be pulsating with two periods equal to one-fifth and one-sixth of the orbital period.

scholarly journals The multiple system Sk-67°18 in the LMC

1995 ◽  
Vol 163 ◽  
pp. 251-253 ◽  
Author(s):  
V. S. Niemela ◽  
W. Seggewiss ◽  
A. F. J. Moffat
Keyword(s):  
Binary System ◽  
Radial Velocity ◽  
Spectral Type ◽  
Orbital Period ◽  
Large Magellanic Cloud ◽  
Primary Component ◽  
Magellanic Cloud ◽  
Bright Star ◽  
High Mass ◽  
Eclipsing Binary

The bright star Sk—67°18 (Brey 5) in the Large Magellanic Cloud (LMC) contains an eclipsing binary system. Our radial velocity study reveals that the orbital period is almost exactly two days. The spectra also show that the star's primary component is not of spectral type WN, but that the star is rather an Of+O type binary where the primary is probably of type O3f*. Furthermore, Sk—67°18 appears to be a high-mass multiple system.

scholarly journals Modelling of an Eclipsing RS CVn Binary: V405 And

2011 ◽  
Vol 7 (S282) ◽  
pp. 199-200
Author(s):  
Krisztián Vida ◽  
Katalin Oláh ◽  
Zsolt Kővári
Keyword(s):  
Light Curve ◽  
Main Sequence ◽  
Magnetic Activity ◽  
Light Curves ◽  
Stellar Structure ◽  
Main Sequence Stars ◽  
M Dwarfs ◽  
Primary Star ◽  
Convective Envelope ◽  
Eclipsing Binary

AbstractV405 And is an ultrafast-rotating (Prot ≈ 0.46 days) eclipsing binary. The system consists of a primary star with radiative core and convective envelope, and a fully convective secondary. Theories have shown that stellar structure can depend on magnetic activity, i.e., magnetically active M-dwarfs should have larger radii. Earlier light curve modelling of V405 And indeed showed this behaviour: we found that the radius of the primary is significantly larger than the theoretically predicted value for inactive main sequence stars (the discrepancy is the largest of all known objects), while the secondary fits well to the mass-radius relation. By modelling our recently obtained light curves, which show significant changes of the spotted surface of the primary, we can find further proof for this phenomenon.

scholarly journals Light Curve and Orbital Period Analysis of the Eclipsing Binary AT Peg

2011 ◽  
Vol 7 (S282) ◽  
pp. 55-56
Author(s):  
Alexios Liakos ◽  
Panagiotis Niarchos ◽  
Edwin Budding
Keyword(s):  
Light Curve ◽  
Orbital Period ◽  
Time Effect ◽  
Light Curves ◽  
Period Analysis ◽  
Eclipsing Binary ◽  
Secular Changes ◽  
Photometric Observations ◽  
Photometric Elements

AbstractCCD photometric observations of the Algol-type eclipsing binary AT Peg have been obtained. The light curves are analyzed with modern techniques and new geometric and photometric elements are derived. A new orbital period analysis of the system, based on the most reliable timings of minima found in the literature, is presented and apparent period modulations are discussed with respect to the Light-Time effect (LITE) and secular changes in the system. The results of these analyses are compared and interpreted in order to obtain a coherent view of the system's behaviour.

scholarly journals KIC 7385478: An Eclipsing Binary with a γ Doradus Component

2017 ◽  
Vol 34 ◽  
Author(s):  
Orkun Özdarcan ◽  
Hasan Ali Dal
Keyword(s):  
Light Curve ◽  
Orbital Period ◽  
Spectroscopic Data ◽  
Primary Component ◽  
Secondary Component ◽  
Photometric Analysis ◽  
Eclipsing Binary ◽  
Cool Star ◽  
Star Activity ◽  
Dominant Period

AbstractWe present spectroscopic and photometric analysis of the eclipsing binary KIC 7385478. We find that the system is formed by F1V + K4III–IV components. Combining results from analysis of spectroscopic data and Kepler photometry, we calculate masses and radii of the primary and the secondary components as M1 = 1.71 ± 0.08 M⊙, M2 = 0.37 ± 0.04 M⊙ and R1 = 1.59 ± 0.03 R⊙, R2 = 1.90 ± 0.03 R⊙, respectively. Position of the primary component in HR diagram is in the region of γ Doradus type pulsators and residuals from light curve modelling exhibit additional light variation with a dominant period of ~ 0.5 d. These are clear evidences of the γ Doradus type pulsations on the primary component. We also observe occasional increase in amplitude of the residuals, where the orbital period becomes the most dominant period. These may be attributed to the cool star activity originating from the secondary component.

scholarly journals Mass transfer and stellar wind effects in the eclipsing binary RT Andromedae

1981 ◽  
Vol 59 ◽  
pp. 491-494
Author(s):  
G.A. Bakos ◽  
J. Tremko
Keyword(s):  
Mass Transfer ◽  
Light Curve ◽  
Spectral Type ◽  
Orbital Period ◽  
Stellar Wind ◽  
Mass Ratio ◽  
Eclipsing Binary ◽  
Short Period ◽  
Photometric Elements ◽  
Number Of Authors

In recent years the short period eclipsing binary RT And has been studied extensively by a number of authors. From photo electric observations the light curve and the photometric elements were derived by Dean (1974) and Mancuso et al. (1979). The geometric dimensions of the binary confirm that the system is detached consisting of two stars of spectral type F8 V and KO V. The mass ratio is 0.66. In spite of this classification, effects appearing among semidetached systems have been observed, namely, variations of the amplitude and the shape of the light curve and changes of the length of the orbital period.

scholarly journals KIC 8553788: A pulsating Algol with an extreme mass ratio

2018 ◽  
Vol 616 ◽  
pp. A130 ◽  
Author(s):  
A. Liakos
Keyword(s):  
Radial Velocity ◽  
Spectral Type ◽  
Primary Component ◽  
Photometric Data ◽  
Light Curves ◽  
Secondary Component ◽  
Mass Ratio ◽  
Eclipsing Binary ◽  
Detached Binaries ◽  
Absolute Parameters

Context. The present research paper focuses on the eclipsing binary KIC 8553788 which belongs to two different types of binary systems regarding its physical properties. In particular, it is one of the 71 oscillating stars of Algol-type that have been discovered so far and one of the six that have been published based on high-cadence photometric data of the Kepler mission. In addition, it is one of the four semi-detached binaries of the group of R CMa-type systems, while its pulsating component has the fourth fastest frequency among the δ Scuti stars-members of semi-detached binaries. Detailed light curves as well as spectroscopic and pulsation analyses are presented, while possible explanation scenarios for the evolution of the system involving past mass transfer, mass loss, and/or angular momentum loss due to the presence of a tertiary component are discussed. Aims. The goal of the study is to extract the pulsational characteristics of the oscillating star of the system, to estimate the absolute parameters of its components, and to provide a possible explanation for its extreme evolutionary status. Methods. Ground-based spectroscopic observations using the 2.3 m “Aristarchos” telescope were obtained and used for the estimation of the spectral type of the primary component and to model the light curves of the system with higher certainty. The short-cadence photometric data provided by the Kepler mission were analysed using standard eclipsing binary modelling techniques, while Fourier analysis was applied on their residuals aiming to reveal the properties of the intrinsic oscillations. The resulting photometric model was combined with a published radial velocity curve to obtain accurate absolute parameters for the components of the system. Results. The results show that the primary component of the system is of A8 spectral type, has a mass of 1.6 M⊙, and a radius of 2 R⊙. It is a relatively fast pulsator of δ Scuti type that oscillates in 89 frequency modes with the dominant one being 58.26 cycles day−1. On the other hand, the secondary component has a mass of only 0.07 M⊙, a radius of 1 R⊙, and a temperature of 4400 K. In addition, it was found to be magnetically active with migrating cool spots on its surface. Conclusions. KIC 8553788, according to its geometrical configuration and its pulsational properties, belongs to the group of oscillating stars of Algol type, while according to its very low mass ratio and its relatively short orbital period belongs also to the group of R CMa stars. If confirmed by radial velocity data of the secondary component, the system would have the lowest mass ratio that has ever been found in semi-detached systems and could therefore be considered as one of the most extreme cases.

scholarly journals New Data on the Eclipsing Binary V1848 Ori and Improved Orbital and Light Curve Solutions

2020 ◽  
Vol 29 (1) ◽  
pp. 72-80 ◽  
Author(s):  
Fatemeh Davoudi ◽  
Atila Poro ◽  
Fahri Alicavus ◽  
Afshin Halavati ◽  
Saeed Doostmohammadi ◽  
...  
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Mass Function ◽  
Light Curves ◽  
Complete Analysis ◽  
Physical Parameters ◽  
Mass Ratio ◽  
Third Body ◽  
Eclipsing Binary

AbstractNew observations of the eclipsing binary system V1848 Ori were carried out using the V filter resulting in a determination of new times of minima and new ephemeris were obtained. We presented the first complete analysis of the system’s orbital period behavior and analysis of O-C diagram done by the GA and MCMC approaches in OCFit code. The O-C diagram demonstrates a sinusoidal trend in the data; this trend suggests a cyclic change caused by the LITE effect with a period of 10.57 years and an amplitude of 7.182 minutes. It appears that there is a third body with mass function of f (m3) = 0.0058 M⊙ in this binary system. The light curves were analyzed using the Wilson-Devinney code to determine some geometrical and physical parameters of the system. These results show that V1848 Ori is a contact W UMa binary system with the mass ratio of q = 0.76 and a weak fillout factor of 5.8%. The O’Connell effect was not seen in the light curve and there is no need to add spot.

scholarly journals U Cephei Revisited

1989 ◽  
Vol 107 ◽  
pp. 355-355
Author(s):  
Burt Nelson ◽  
Walter D. Davis
Keyword(s):  
Light Curve ◽  
Floppy Disk ◽  
Light Curves ◽  
Eclipsing Binary

Observations of U Cephei made by C. M. Huffer, et al, in 1950-51 and in 1959, are presented here to contrast with other observations made by Huffer and others.In many cases, to see a light-curve of an eclipsing binary is to see all light-curves for that particular system. This is certainly not true of U Cephei which, because of its rapid variations, has held the attention of so many for so long.The 1950-51 yellow and blue observations were made at Washburn Observatory, Madison. The data have been transcribed from Huffer’s note books to a floppy disk and are available.

scholarly journals The Eclipses of the Close Binary Star BE UMa

1996 ◽  
Vol 158 ◽  
pp. 471-472
Author(s):  
Janet H. Wood ◽  
E. L. Robinson ◽  
E.-H. Zhang
Keyword(s):  
Light Curve ◽  
High Speed ◽  
Binary Star ◽  
Light Curves ◽  
Close Binary ◽  
Primary Star ◽  
Secondary Star ◽  
Different Depths ◽  
The Mean ◽  
Close Binary Star

BE UMa is a close binary star, not transferring mass, with an extremely hot primary star irradiating the inner face of the cool secondary star. The light curve shows a large-amplitude, sinusoidal variation with a period of 2.29 d, and an eclipse that is centered on the minimum of the variation [1], [3]. According to [1], the eclipse is partial, not total. However, it has been argued [2] that the eclipse was really flat bottomed and thus total. This has important repercussions for the deduced model of the system. To resolve this issue we obtained simultaneous UBVR photometry of BE UMa using the Stiening 4-channel, high-speed photometer on the 82-inch telescope at McDonald Observatory. The mean light curves are shown in Fig. 1. The eclipse in all colours is round bottomed and partial. The different depths are caused by the different contribution from the red secondary star in each bandpass.

scholarly journals δ Sct-Type Pulsators in Eclipsing Binary Systems: the Case of RZ Cas

2002 ◽  
Vol 185 ◽  
pp. 102-103
Author(s):  
E. Rodríguez ◽  
V. Costa ◽  
M.J. López-González ◽  
J.M. García ◽  
S.L. Kim ◽  
...  
Keyword(s):  
Binary System ◽  
Binary Systems ◽  
Hot Spot ◽  
Primary Component ◽  
Roche Lobe ◽  
Light Curves ◽  
Eclipsing Binary ◽  
Preliminary Results ◽  
The Impact

AbstractRZ Cas is an Algol-type eclipsing binary system where the primary component was recently discovered as a δ Set pulsator. A three-continent multisite photometric campaign was carried out during 1999. Preliminary results are reported here indicating a semi-detached system where the secondary fills its Roche lobe. The light curves also suggest a hot spot on the surface of the primary component as a consequence of the impact of the mass stream from the secondary. The pulsational behaviour can be well described with only one frequency.

Sign in / Sign up

Export Citation Format

Share Document