共查询到20条相似文献,搜索用时 31 毫秒
1.
U. S. Chaubey 《Astrophysics and Space Science》1992,189(2):263-270
TheU, B, andV photometric observations of the eclipsing binary MM Cas have been presented and discussed. The photometric elements have been derived. By use of the colour indicesU-B andB-V, the spectral types of the systemic components are estimated. An examination of all available times of minimum light of MM Cas does not reveal any change in its orbital period. 相似文献
2.
Using Wood's model we have reanalyzed the light curves of the eclipsing binaries QY Aql, V388 Cyg, and HS Her. For QY Aql and HS Her our photometric solutions substantially confirm previous results, thus respectively supporting ansd-d classification and a main sequence detached view. On the other hand, significantly different photometric elements have been derived for V388 Cyg, which is likely to be an evolved contact binary. 相似文献
3.
. Bulut C. iek A. Erdem V. Bakis O. Demircan
. L. Deirmenci 《Astronomische Nachrichten》2006,327(9):912-916
The first ground‐based BVR photometric observations of the recently discovered eclipsing binary V744 Cas are presented. From these measurements, timings for two primary and one secondary minima have been calculated. The light curves of the system were analyzed by using the Wilson‐Devinney program. The analysis shows that the system is detached with two similar components of spectral type A2V, and the orbit is eccentric (e = 0.0662 ± 0.0005). The longitude of the periastron (ω) was found significantly different for two different light curves (ours and that of Hipparcos), which is strongly suggestive of an apsidal motion with a period of about 425 ± 68 yr. This makes V744 Cas an important candidate for studies of apsidal motions. The first estimate of the absolute dimensions place the system close to the terminal age of the main sequence (TAMS) in the HR diagram. The distance from the spectroscopic parallax (d = 740 ± 10 pc) was found to be slightly larger than the Hipparcos distance of d = 610 ± 400 pc. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
4.
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. 相似文献
5.
M. C. Akan 《Astrophysics and Space Science》1987,135(1):157-167
The long-period eclipsing binary star V367 Cygni has been observed photoelectrically in two colours,B andV, in 1984, 1985, and 1986. These new light curves of the system have been discussed and compared for the light-variability with the earlier ones presented by Heiser (1962). Using some of the previously published photoelectric light curves and the present ones, several primary minima times have been derived to calculate the light elements. Any attempt to obtain a photometric solution of the binary is so complicated by the peculiar nature of the light curve caused by the presence of the circumstellar matter in the system. Despite this difficulty, however, some approaches are being carried out to solve the light curves which will be discussed shortly. 相似文献
6.
Multi-colourWBVR photoelectric observations of the eclipsing binaries IT Cas, CO Cep, and AI Hya were carried out. The photometric elements and the absolute parameters of the orbits and components were obtained. The valuation of the angular rate of the apsidal motion of AI Hya based on the comparison of our observations with the previous photoelectric light curve of this system was derived. 相似文献
7.
The V light curve of eclipsing binary LD355 was analyzed by using the latest version of Wilson Program in order to derive photometric elements of this system. Since no spectroscopic mass ratio is available, the q‐search method was applied to yield the preliminary range of mass ratio in order to search for the final solution. The solution was performed by assuming detached (mode 2) and semi‐detached (mode 5) configurations, since no classification of the system based on the shape of light curve is possible. The solution in mode 5 leads to an acceptable model. The present solution reveals that LD355 has a photometric mass ratio q = 0.178 and is a semi‐detached binary with the secondary component filling the Roche lobe. 相似文献
8.
In this study we present photometric observations of the eclipsing binary KR Cyg made in 1999 and 2000. The observations of
the eclipsing binary KR Cyg have been carried out in B, V and R colours at the Ege University Observatory. A new seasonal
light curves are presented. New times of minima and ephemerides are given. Based on a statistical analysis of the times of
minima obtained by photoelectric photometry, the orbital period of the system is found to be constant. The photometric mass
ratio of the system is well determined. The corresponding light curves were analyzed by the Wilson-Devinney code.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
The aim of the present paper is to analyze the light variation as well as the period changes of the eclipsing binary RZ Cas. New photometric elements are computed using the frequency-domain method. The possibility of the light-time effect and the apsidal motion is discussed. 相似文献
10.
Photoelectric light curves of the eclipsing binary RZ Cas are presented forB andV filters. The light curves are analysed for light and geometrical elements, starting with a previously suggested preliminary method. The approximate results thus obtained are then optimised through the Wilson-Devinney computer programs. 相似文献
11.
Following a brief history of measurement of eclipsing binary mass ratios from light curves, we show that photometric mass
ratios for overcontact and semi-detached binaries are reliable because the relative stellar radii, R/a, are accurately measured and not, as commonly claimed, because of information in the light variation outside eclipse. We
explore the accuracy of photometric mass ratios by solving synthetic data of typical precisions for a semi-detached and an
overcontact binary for orbital inclinations from 89∘ down into the partial eclipse range. 相似文献
12.
The first light curve solutions and period study of two contact binary systems: V1370 Tau and QQ Boo
《New Astronomy》2021
The first light curve solutions of the binary systems V1370 Tau and QQ Boo are presented. The periodic changes are calculated, and a new ephemeris presented for each of these two binary systems. O-C analysis is performed using the MCMC method in OCFit code. The changing rate of period was measured as dP/dt= 0.2423 days/year for V1370 Tau and dP/dt= -0.1363 days/year for QQ Boo. The light curve solutions suggest that V1370 Tau is a weak-contact eclipsing binary system with a photometric mass ratio q = 0.829, and that the corresponding fillout factor is 11.06%. Furthermore, it is suggested that the QQ Boo binary system is also a weak-contact W UMa eclipsing binary with a photometric mass ratio q = 0.831, and that its fillout factor equals 10.26%. The light curve solutions require cold spots. Utilizing the Wilson-Devinney code the photometric and geometric parameters of the systems are determined. The distance of both V1370 Tau and QQ Boo are calculated according to the estimated absolute parameters as 159.95 ± 23 pc and 309.03 ± 25 pc, respectively, which are in a good agreement with the distance values derived from the Gaia DR2 parallax within one standard deviation. Moreover, the positions of their components on the H-R diagram are represented. 相似文献
13.
We present a photometric analysis of the eclipsing binary systemGSC4832.400 based on 732 photometric observations obtained on sixteen clear nights during 1999–2000 in the V-Johnson and yb-Strömgren filters. The observed times of the minima yielded a linear ephemeris showing that the system has a constant period of 0.313150 ± 0.000002days. The light curve corresponds to a circular orbit for the system and clearly shows that GSC4832.400 has the defining characteristics of a W UMa-type eclipsing binary. It also shows a small O'Connell effect, which could be due to the presence of a hot spot in the primary star. A preliminary photometric solution based on the assumption of an over contact systemsatis factorily reproduced the observed light curve. 相似文献
14.
UBV photoelectric observations of the W UMa-type binary V471 Cas were made from September to November 1984. Its colour indices were found to be(B-V)=0
.
m
771±0
.
m
02 and(U-B)=0
.
m
196±0
.
m
02. TheU, B, andV light curves of V471 Cas show some photometric fluctuations. We found that its orbital period is not 0.335998 days which was given by GCVS (1986), but 0.405356 days.Photometric orbital elements of V471 Cas were found using the Wilson-Devinney method. V471 Cas is a contact system, in which the overcontact factor is 0.19, its mass ratio of two components is 0.5947, and orbital minclination is in 83.29 degrees. 相似文献
15.
Huseyin Alkan 《Astrophysics and Space Science》1981,75(2):455-463
UBV Light Curves of the eclipsing binary system PV Cassiopeiae have been investigated using recently developed frequency-domain techniques. This analysis is based on Kopal's new theory for the study of the light variations, between minima as well as within eclipses, of eclipsing binaries whose components undistorted or distorted by axial rotation and mutual tidal action.A method for the distinguishing of the photometric proximity and eclipse effects directly from the observed data is also presented. In this method no rectification is needed. The automated method has been tested successfully on the light curves of PV Cassiopeiae. Finally, a comparative discussion is given of Kopal's and Kitamura's methods of the light curves analysis. 相似文献
16.
We present high-precision,multi-band CCD photometry of two less-studied close binaries V1123 Tau and V1128 Tau.Complete covered light curves and a number of new times of light minima of the two eclipsing systems were obtained,based on which,revised orbital elements and new ephemerides were given.By adopting the Wilson-Devinney method,the light curves were analyzed.The photometric solutions confirm the W UMa-type nature of the binary systems.With the less-massive secondary slightly cooler than the primary,V1... 相似文献
17.
New BVR light curves and a photometric analysis of the eclipsing binary star V1430 Aql are presented. The light curves were obtained at the Çanakkale Onsekiz Mart University Observatory in 2004. The light curves are generally those of detached eclipsing binaries, but there are large asymmetries between maxima. New BVR light curves were analysed with an ILOT procedure. Light curve asymmetries of the system were explained in terms of large dark starspots on the primary component. The primary star shows a long‐lived and quasi‐poloidal spot distribution with active longitudes in opposite hemispheres. Absolute parameters of the system were derived.We also discuss the evolution of the system: the components are likely to be pre‐main sequence stars, but a post‐main sequence stage cannot be ruled out. More observations are needed to decide this point. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
18.
St. Raetz M. Vako M. Mugrauer T.O.B. Schmidt T. Roell T. Eisenbeiss M. M. Hohle A. Koeltzsch Ch. Ginski C. Marka M. Moualla N. Tetzlaff Ch. Broeg R. Neuhuser 《Astronomische Nachrichten》2009,330(5):504-510
We report on observations of the eclipsing binary 2MASS 19090585+4911585 with the 25 cm auxiliary telescope of the University Observatory Jena. We show that a nearby brighter star (2MASS 19090783+4912085) was previously misclassified as the eclipsing binary and find 2MASS 19090585+4911585 to be the true source of variation. We present photometric analysis of VRI light curves. The system is an overcontact binary of W UMa type with an orbital period of (0.288374 ± 0.000010) d (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
19.
Using WOOD 's (1972) model we have analyzed MEINUNGER 's (1977) B and V photoelectric light curves – as yet unsolved–of the W UMa-type eclipsing binary AZ Vir, for which no photometric elements have as yet been determined. Our results describe AZ Vir as a contact pair in which the star eclipsed at the deeper minimum is smaller than its companion. AZ Vir appears to conform to the general properties of the W-type subclass of W UMa systems. 相似文献
20.
本文给出了首次食双星V375 Cas的BV两色光电测光资料和新的历元,并用Wilson-Devinney综合光变曲线方法取得测光解。结果表明:V375 Cas是一个类似RZ Dra的早型半相接双星系统,小质量子星充满了临界等位面,而大质量子星几乎充满了临界等位面,此星对于了解早型密近双星的演化是很有意义的。 相似文献