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.

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 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 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 Low Color Temperature Variations over the Common Envelope of W Ursae Majoris and the Cause of Its W-Type Light Curve

1980 ◽  
Vol 88 ◽  
pp. 501-503
Author(s):  
J. A. Eaton ◽  
C. - C. Wu ◽  
S. M. Rucinski
Keyword(s):  
Light Curve ◽  
Ultraviolet Light ◽  
Surface Brightness ◽  
Light Curves ◽  
Color Temperature ◽  
Temperature Variations ◽  
Eclipsing Binary ◽  
Common Envelope ◽  
Temperature Excess ◽  
The Common

We discuss ultraviolet photometry of the eclipsing binary W Ursae Majoris obtained with the Groningen instruments on the Astronomical Netherlands Satellite (ANS). Fifty measurements of this star's brightness were obtained for each of the bandpasses at 2200, 2500, and 3300 Å. This new data is significantly more precise than Rucinski's OAO-2 photometry, enabling us to draw definitive conclusions about the distribution of brightness on the surface of W UMa. The ultraviolet light curves are generally similar in shape to those for optical passbands; the amplitudes are greater in the UV, while the depths of the primary and secondary eclipses are nearly equal at both 2200 and 2500 Å. We have analyzed the (2200 − 3300) color curve to determine how much the color temperature varies over the common envelope, concluding that any such temperature variations must be small. In terms of the traditional surface-brightness parameters for gravity darkening, temperature excess of the smaller component, and bolometric albedo, we find β = 0.03 ± 0.01, X = ΔT/T = 0.000 ± 0.009, and Abol = 0.4 ± 0.4. Further, we conclude that the star is limb darkened considerably more at 2200 than at 3300 Å.

scholarly journals BVRcIc Observations and Analysis of the Near-Contact Solar Type Eclipsing Binary, V530 Andromedae

2013 ◽  
Vol 2013 ◽  
pp. 1-8
Author(s):  
Ronald G. Samec ◽  
Daniel Flaaten ◽  
James Kring ◽  
Danny R. Faulkner
Keyword(s):  
Light Curve ◽  
Undergraduate Research ◽  
Initial Period ◽  
Light Curves ◽  
Eclipsing Binary ◽  
Massive Component ◽  
Solar Type ◽  
First Time ◽  
Curve Solution ◽  
Light Curve Solution

We present the first precision UBVRcIc light curves, an initial period study, and a simultaneous light curve solution for the near-contact solar type eclipsing binary V530 And. Our observations were taken with the 0.81 m Lowell reflector on 27 and 29 September, 2011, with time being granted from the National Undergraduate Research Observatory (NURO). Our Wilson Devinney Program solution yields a semidetached, V1010 Oph configuration: the more massive component is filling its Roche lobe. The system is apparently approaching contact for the first time. It is not a classic Algol.

scholarly journals A search for pulsations in two Algol-type systems V1241 Tau and GQ Dra

2013 ◽  
Vol 9 (S301) ◽  
pp. 507-508 ◽  
Author(s):  
Burak Ulaş ◽  
Ceren Ulusoy ◽  
Kosmas Gazeas ◽  
Naci Erkan ◽  
Alexios Liakos
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Type Systems ◽  
Light Variation ◽  
Light Curves ◽  
Eclipsing Binary ◽  
Photometric Observations ◽  
Fourier Techniques ◽  
Photometric Elements

AbstractWe present new photometric observations of two eclipsing binary systems, V1241 Tau and GQ Dra. We use the following methodology: initially, the Wilson-Devinney code is applied to the light curves in order to determine the photometric elements of the systems. Then, the residuals are analysed using Fourier techniques. The results are the following. One frequency can be possibly attributed to a real light variation of V1241 Tau, while there is no evidence of pulsations in the light curve of GQ Dra.

scholarly journals The Effect of Circumstellar Material on the Light Curves of Eclipsing Binary Systems

2011 ◽  
Vol 28 (4) ◽  
pp. 290-298
Author(s):  
S. M. R. Ghoreyshi ◽  
J. Ghanbari ◽  
F. Salehi
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Outer Radius ◽  
Accretion Disc ◽  
Light Curves ◽  
Jet Stream ◽  
Eclipsing Binary ◽  
Circumstellar Material ◽  
Disc Model ◽  
Free Parameters

AbstractThis study inspects the influence of various effects and free parameters of the accretion disc and circumstellar material on the emerging light curve of eclipsing binary systems that have a circumstellar disc, by using the SHELLSPEC code. The results indicate that some of the parameters, namely the temperature and inclination of the disc, spot, jet, stream and shell, significantly affect on the emerging light curve, while some other parameters, namely the exponent of the power-law behavior of the density of the disc, microturbulence, inner and outer radius of the disc, do not noticeably affect on the emerging light curve. An application to the Algol-type eclipsing binary system AV Del and an accretion disc model for the system using the SHELLSPEC code is included.

scholarly journals Scanner observations of some close binary systems

1986 ◽  
Vol 118 ◽  
pp. 261-263
Author(s):  
D. J. Sullivan ◽  
M. Walkington ◽  
E. Budding
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Light Curves ◽  
Close Binary ◽  
Eclipsing Binary ◽  
Close Binary Systems

Using our intermediate bandwidth photometric scanner, we have obtained light curve data at a range of spectral intervals for a number of close eclipsing binary systems. This paper reports briefly on the instrumentation system, the data obtained for two of the variables AE Phe and ε CrA, and a preliminary modelling of the light curves.

scholarly journals BEER analysis of Kepler and CoRoT light curves – V. eBEER: extension of the algorithm to eccentric binaries

2020 ◽  
Vol 497 (4) ◽  
pp. 4884-4895
Author(s):  
M Engel ◽  
S Faigler ◽  
S Shahaf ◽  
T Mazeh
Keyword(s):  
Light Curve ◽  
Radial Velocity ◽  
Binary Systems ◽  
Light Curves ◽  
Harmonic Series ◽  
Eclipsing Binary ◽  
Fast Processing

ABSTRACT We present an extension of the BEER model for eccentric binaries – eBEER, approximating the BEaming, Ellipsoidal, and Reflection effects by harmonic series of the Keplerian elements of their orbit. As such, it can be a tool for fast processing of light curves for detecting non-eclipsing eccentric binary systems. To validate the applicability of the eccentric model and its approximations, we applied eBEER to the Kepler light curves, identified a sample of bright non-eclipsing binary candidates, and followed three of them with the Wise observatory eShel spectrograph. After confirming the three systems are indeed radial velocity (RV) binaries, we fitted the light curves and the RV data with PHOEBE, a detailed numerical light curve and RV model, and showed that the PHOEBE derived parameters are similar to those obtained by the eBEER approximation.

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