scholarly journals Synthetic Light Curve Analysis of the Close Binary Systems BX Andromedae and RR Leporis

1989 ◽  
Vol 107 ◽  
pp. 359-360
Author(s):  
R.G. Samec ◽  
R.E. Fuller ◽  
R. H. Kaitchuck ◽  
B. B. Bookmyer ◽  
D. R. Faulkner
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Thermal Relaxation ◽  
Curve Analysis ◽  
Light Curves ◽  
Close Binary ◽  
Comparison Star ◽  
Short Time Scale ◽  
Light Curve Analysis ◽  
Short Period

AbstractUnpublished photoelectric observations of the systems BX And and RR Lep were subjected to light curve analysis using the Wilson-Devinney Code.The short-period eclipsing binary system BX And was observed on five nights in 1976 at the Morgan-Monroe station of the Goethe Link Observatory of Indiana University. The observations covering the eclipse portions of the light curves yielded four times of minimum light. A period study covering 89 years of observations confirms that a major period change took place about 1950. The system is suspected of being quite active on a short time scale. Standard magnitudes were derived for BX And and for the comparison star. The corrected color indices indicate that BX And and the comparison star BD+39° 476 are in the spectral range of F3-F5. The light curves, defined by 1092 observations in B, 1097 in V and 971 in the U filter are symmetric. The difference in the eclipse depths are quite large averaging 0.m46. A distinct de-reddening of the light curves occurs during the secondary eclipse. The first synthetic light curve solutions of the system were obtained. The solution of BX And indicates that the system consists of an F-type primary and a K-type secondary component in a state of shallow contact. This result is supported by the location of BX And on the Eggen period-color diagram for contact binaries. The large mass ratio, temperature disparity and period increase are found to be consistent with an early contact phase of thermal relaxation oscillations.

scholarly journals High-Level Magnetic Activity on a Low-Mass Close Binary: GSC 02038-0293

2012 ◽  
Vol 29 (2) ◽  
pp. 150-160 ◽  
Author(s):  
H. A. Dal ◽  
E. Sipahi ◽  
O. Özdarcan
Keyword(s):  
Light Curve ◽  
Active Component ◽  
Magnetic Activity ◽  
Curve Analysis ◽  
Light Curves ◽  
Close Binary ◽  
Physical Parameters ◽  
Light Curve Analysis ◽  
Low Mass ◽  
High Level

AbstractTaking into account results obtained from light-curve analysis and out-of-eclipse analyses, we discuss the nature of GSC 02038-00293 and also its magnetic activity behaviour.We obtained light curves of the system during observing seasons 2007, 2008 and 2011. We obtained its secondary minimum clearly in I-band observations in 2008 for the first time. Analysing this light curve, we found the physical parameters of the components. The light-curve analysis indicates that the possible mass ratio of the system is 0.35. We obtained the remaining V-band light curves, extracting the eclipses. We modelled these remaining curves using the SPOTMODEL program and found possible spot configurations of the magnetically active component for each observing season. The models demonstrated that there are two active longitudes for the active component. The models reveal that both active longitudes migrate in the direction of decreasing longitude. We also examined the light curves in out-of-eclipse phases with respect to minimum and maximum brightness, amplitude, etc. The amplitude of the curves during out-of-eclipse phases varies in a sinusoidal way with a period of ∼8.9 yr; the mean brightness of the system is dramatically decreasing. The phases of the deeper minimum during out-of-eclipse periods exhibit a migration toward decreasing phase.

Synthetic light curve analysis of the close binary systems BX Andromedae and RR Leporis

1989 ◽  
Vol 50 (1-2) ◽  
pp. 359-360
Author(s):  
R.G. Samec ◽  
R.E. Fuller ◽  
R.H. Kaitchuck ◽  
B.B. Bookmyer ◽  
D.R. Faulkner
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Curve Analysis ◽  
Close Binary ◽  
Light Curve Analysis ◽  
Close Binary Systems

Synthetic Light Curve Analysis of the Close Binary Systems BX Andromedae and RR Leporis

Algols ◽  
1989 ◽  
pp. 359-360
Author(s):  
R. G. Samec ◽  
R. E. Fuller ◽  
R. H. Kaitchuck ◽  
B. B. Bookmyer ◽  
D. R. Faulkner
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Curve Analysis ◽  
Close Binary ◽  
Light Curve Analysis ◽  
Close Binary Systems

Light curve analysis of six totally eclipsing W UMa binaries

2020 ◽  
Author(s):  
Olivera Latković ◽  
Atila Čeki
Keyword(s):  
Light Curve ◽  
Parameter Space ◽  
Curve Analysis ◽  
Light Curves ◽  
Evolutionary Status ◽  
Search Procedure ◽  
Light Curve Analysis ◽  
Short Period ◽  
Mass Ratios ◽  
First Time

Abstract We analyze multicolor light curves of six totally eclipsing, short-period W UMa binaries and derive, for the first time, their orbital and stellar parameters. The mass ratios are established robustly through an automated q-search procedure that performs an heuristic survey of the parameter space. Five stars belong to the W and one to the A subtype. The mass ratios range from 0.23 to 0.51 and the fillouts from $10\%$ to $15\%$. We estimate the ages and discuss the evolutionary status of these objects in comparison with a sample of other short-period W UMa binaries from the literature.

Quasi-Periodic Oscillations in Dwarf Novae

1979 ◽  
Vol 46 ◽  
pp. 77-88
Author(s):  
Edward L. Robinson
Keyword(s):  
Binary Systems ◽  
Outer Edge ◽  
Light Curves ◽  
Close Binary ◽  
Bright Spot ◽  
Dwarf Novae ◽  
Periodic Oscillations ◽  
High Frequencies ◽  
Short Period ◽  
Typical Time

Three distinct kinds of rapid variations have been detected in the light curves of dwarf novae: rapid flickering, short period coherent oscillations, and quasi-periodic oscillations. The rapid flickering is seen in the light curves of most, if not all, dwarf novae, and is especially apparent during minimum light between eruptions. The flickering has a typical time scale of a few minutes or less and a typical amplitude of about .1 mag. The flickering is completely random and unpredictable; the power spectrum of flickering shows only a slow decrease from low to high frequencies. The observations of U Gem by Warner and Nather (1971) showed conclusively that most of the flickering is produced by variations in the luminosity of the bright spot near the outer edge of the accretion disk around the white dwarf in these close binary systems.

scholarly journals PELICAN: deeP architecturE for the LIght Curve ANalysis

2019 ◽  
Vol 627 ◽  
pp. A21 ◽  
Author(s):  
Johanna Pasquet ◽  
Jérôme Pasquet ◽  
Marc Chaumont ◽  
Dominique Fouchez
Keyword(s):  
Light Curve ◽  
Sampling Rate ◽  
Real Data ◽  
Curve Analysis ◽  
Irregular Sampling ◽  
Light Curves ◽  
Light Curve Analysis ◽  
Deep Architecture ◽  
Deep Fields

We developed a deeP architecturE for the LIght Curve ANalysis (PELICAN) for the characterization and the classification of supernovae light curves. It takes light curves as input, without any additional features. PELICAN can deal with the sparsity and the irregular sampling of light curves. It is designed to remove the problem of non-representativeness between the training and test databases coming from the limitations of the spectroscopic follow-up. We applied our methodology on different supernovae light curve databases. First, we tested PELICAN on the Supernova Photometric Classification Challenge for which we obtained the best performance ever achieved with a non-representative training database, by reaching an accuracy of 0.811. Then we tested PELICAN on simulated light curves of the LSST Deep Fields for which PELICAN is able to detect 87.4% of supernovae Ia with a precision higher than 98%, by considering a non-representative training database of 2k light curves. PELICAN can be trained on light curves of LSST Deep Fields to classify light curves of the LSST main survey, which have a lower sampling rate and are more noisy. In this scenario, it reaches an accuracy of 96.5% with a training database of 2k light curves of the Deep Fields. This constitutes a pivotal result as type Ia supernovae candidates from the main survey might then be used to increase the statistics without additional spectroscopic follow-up. Finally we tested PELICAN on real data from the Sloan Digital Sky Survey. PELICAN reaches an accuracy of 86.8% with a training database composed of simulated data and a fraction of 10% of real data. The ability of PELICAN to deal with the different causes of non-representativeness between the training and test databases, and its robustness against survey properties and observational conditions, put it in the forefront of light curve classification tools for the LSST era.

scholarly journals Synthetic Light-Curve Analysis of a Short Period Binary System YY Eri

2021 ◽  
Vol 58 (1) ◽  
pp. 5454-5456
Author(s):  
Warisa Pancharoen, Wiraporn Maithong
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Effective Temperature ◽  
Curve Analysis ◽  
Photometric System ◽  
Mass Ratio ◽  
Light Curve Analysis ◽  
The Public ◽  
Secondary Star ◽  
Short Period

YY Eri, the short-period binary system, is a W UMa type of the eclipsing binary system. This study using a 0.7-meter telescope with CCD photometric system in B V and R filters. It was observed at the Regional Observatory for the Public, Chachoengsao, Thailand on December 5, 2018, UT. The MaxIm DL software was used to analyzed the images photometry to produce the light curve. The Wilson-Devinney technique was computed the synthetic light curve that prefer to the physical properties of the YY Eri. The results show that the effective temperature of the primary and secondary star was 5533 and 5598 K, respectively. The inclination is 81.450 and the mass ratio is 0.55. The degree of contact was calculated as 16.64%  

scholarly journals Light curve analysis of the eclipsing binary system V781 Tau

2021 ◽  
Vol 2145 (1) ◽  
pp. 012005
Author(s):  
N Lamlert ◽  
W Maithong
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Orbital Period ◽  
Binary Systems ◽  
Curve Analysis ◽  
Photometric System ◽  
Light Curve Analysis ◽  
Eclipsing Binary ◽  
The Public ◽  
Secondary Star

Abstract V781 Tau is one of W UMa eclipsing binary systems whose orbital period is 0.34 days. The 0.7-meter telescope with CCD photometric system in B and V filters was conducted at the Regional Observatory for the Public, Chachoengsao, Thailand during December 2018, UT. The Wilson-Devinney Technique was used for calculating the physical properties of V781 Tau. The results showed the inclination of their orbital is 66.140°±0.14. The effective temperature of the primary and secondary star is 6,060 and 5,881 K, respectively and the degree of contact is 4.38 %

VRI photometry and light curve analysis of short period W UMa-Type 1SWASP J222514.69 + 361643.0

New Astronomy ◽  
2017 ◽  
Vol 56 ◽  
pp. 50-53
Author(s):  
M.H. El-Depsey ◽  
M.S. Abo-Alazm ◽  
M.S. Saad ◽  
I.A. Hassan ◽  
A.M.K. Shaltout ◽  
...  
Keyword(s):  
Light Curve ◽  
Curve Analysis ◽  
Light Curve Analysis ◽  
Short Period

Investigation on the mass transferring near-contact binary TT Cet

2020 ◽  
Vol 37 ◽  
Author(s):  
Xiao-Man Tian ◽  
Lin-Feng Chang
Keyword(s):  
Mass Transfer ◽  
Light Curve ◽  
Hot Spot ◽  
Relaxation Oscillation ◽  
Thermal Relaxation ◽  
Light Curves ◽  
Primary Star ◽  
Contact Stage ◽  
Short Period ◽  
Contact Binary

Abstract First multi-colour complete light curves and low-resolution spectra of short-period eclipsing binary TT Cet are presented. The stellar atmospheric parameters of the primary star were derived through spectra fitting as: $T_{eff}=7\,091\pm124\,{\text{K}}$ , $\log g = 4.15\pm0.33\,{\text{cm}}/\text{s}^2$ , and $[Fe/H]=-0.23\pm0.04\,\text{dex}$ . The light curves were analysed using the Wilson–Devinney code. The photometric solution suggests that this target should be a near-contact binary with the primary component filling its critical Roche lobe (i.e. SD1-type NCB). The luminosity enhancement around the primary light maximum (phase 0.10–0.40) on the light curve was detected like other SD1-type NCBs, which could be caused by a hot spot near the facing surface of the secondary component due to mass transfer. Long-term decrease of the orbital period at a rate of $dP/dt=-5.01\,({\pm}0.06)\times 10^{-8}\,{{\text{d}} \cdot{yr}}^{-1}$ was detected by the O–C analysis, which supports the mass transfer from the primary to the secondary and is consistent with its primary filling configuration. No third body was found through the light curve and O–C analysis. TT Cet may locate in the broken contact stage predicted by the thermal relaxation oscillation theory (TRO) and will evolve to the contact stage eventually. It is another good observational example supporting the TRO theory. We have collected all known SD1-type NCBs with absolute parameters from the literatures. The relations of these parameters are summarised for these rare systems.

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