- ID:
- ivo://CDS.VizieR/J/A+AS/131/395
- Title:
- Eclipsing binaries light curves models
- Short Name:
- J/A+AS/131/395
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present parameters used in the investigation of the light curves of eclipsing binaries together with other data needed for the interpretation of their stellar and dynamical evolution. Parameters include limb-darkening coefficients and gravity darkening exponents, while data include the apsidal motion constants, the moment of inertia, and the potential energy. The adopted stellar models are those computed by Claret (1995, Cat. <J/A+AS/109/441>) for a representative chemical composition of X=0.70 and Z=0.02. In addition to the parameters needed for the study of the dynamical behavior and tidal evolution of binary systems, we supply the linear limb-darkening coefficients computed in 12 different photometric bands, as well as the gravity darkening exponent for each point along the evolutionary track. We have developed a method, based on the triangles strategy by Kippenhahn et al. 1967 to compute the gravity-darkening exponent using interior models. For the first time, the gravity-darkening exponents are presented as a function of mass and age. The old values of {beta}_1_ (0.32 and 1.0 for convective and radiative envelopes) are thus superseded by the present calculations and a smooth transition is achieved between both energy transport mechanisms. The tables presented here assist modeling of the light curves of close binaries using limb-darkening and gravity darkening coefficients which are consistent with the observed masses, radii and effective temperatures. In order to facilitate the use of the grid of models presented here in a variety of different research fields other than binary stars, synthetic colors (U-B, B-V, u-b, b-y) and M_v_ are also given.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/457/836
- Title:
- Eclipsing binaries MgI b and H{alpha} EW
- Short Name:
- J/MNRAS/457/836
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I have reinterpreted Rucinski's line profiles (broadening functions) for the hot A-type W Ursae Majoris binary AW UMa in terms of various contact models, finding that the detached/semidetached geometry he postulates does not fit the system's light variation or its line profiles. The highly overcontact geometry that actually fits the system's ellipsoidal light variation reproduce the total breadth of the lines but give profiles too broad to fit their shapes. The best solution to this dilemma is differential rotation of both stars in which the mid-latitudes are rotating 20-30 per cent slower than synchronously. This approach preserves the traditional light-curve solution and explains the drift of ripples seen in the line profiles. In addition, there are obviously other flows superimposed on the rotation which make the profiles asymmetrical. Fitting the line profiles is complicated by uncertainties in how the equivalent widths of the lines change with effective temperature and how much they are limb darkened. The contribution of any point on the stellar surface to the equivalent width depends only very weakly on local temperature throughout the range of W UMa binaries. The limb darkening of the lines is probably small, although the effect remains unexplored. I also speculate about the nature of hypothetical star-spots in this system.
- ID:
- ivo://CDS.VizieR/J/AJ/158/106
- Title:
- Eclipsing binaries RVs from APOGEE spectra
- Short Name:
- J/AJ/158/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic eclipsing binaries (SEBs) are fundamental benchmarks in stellar astrophysics and today are observed in breathtaking detail by missions like the Transiting Exoplanet Survey Satellite (TESS), Kepler, and Apache Point Observatory Galactic Evolution Experiment (APOGEE). We develop a methodology for simultaneous analysis of high-precision Kepler light curves and high-resolution near-infrared spectra from APOGEE and present orbital solutions and evolutionary histories for a subset of SEBs within this overlap. Radial velocities extracted from APOGEE spectra using the broadening function (BF) technique are combined with Kepler light curves and to yield binary orbital solutions. The BF approach yields more precise radial velocities than the standard cross-correlation function, which in turn yields more precise orbital parameters and enables the identification of tertiary stars. The orbital periods of these seven SEBs range from 4 to 40 days. Four of the systems (KIC 5285607, KIC 6864859, KIC 6778289, and KIC 4285087) are well-detached binaries. The remaining three systems have apparent tertiary companions, but each exhibit two eclipses along with at least one spectroscopically varying component (KIC 6449358, KIC 6131659, and KIC 6781535). Gaia distances are available for four targets which we use to estimate temperatures of both members of these SEBs. We explore evolutionary histories in H-R diagram space and estimate ages for this subset of our sample. Finally, we consider the implications for the formation pathways of close binary systems via interactions with tertiary companions. Our methodology combined with the era of big data and observation overlap opens up the possibility of discovering and analyzing large numbers of diverse SEBs, including those with high flux ratios and those in triple systems.
- ID:
- ivo://CDS.VizieR/J/A+A/326/1044
- Title:
- Eclipsing binaries uvbyHbeta photometry
- Short Name:
- J/A+A/326/1044
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Systematic differences in photometric stellar surface gravity determination are studied by means of the comparison with empirical values derived from detached double-lined eclipsing binaries. Photometric gravities were computed using Moon & Dworetsky (1985MNRAS.217..305M) grids based on Kurucz (1979ApJS...40....1K) atmosphere models, and empiric al gravities were taken from Andersen (1991A&ARv...3...91A). Individual Stroemgren colours and {beta} indices of each component of the binary system have to be taken into account to correctly analyze the observed differences. A compilation of data on a sample containing 30 detached double-lined eclipsing binaries with accurate (=~1-2%) determination of mass and radius and available uvbyH_{beta}_ photometric data is also presented. Correction of the differences in terms of T_eff_ and logg for the range 11000K<T_eff_<20000K reduces the mean residuals from 0.13dex to 0.07dex. For the range 7000K<T_eff_<8500K, the consideration of metallicity effects by means of {delta}m_o_ index improves the accuracy from 0.20dex to 0.09dex.
- ID:
- ivo://CDS.VizieR/J/A+A/324/137
- Title:
- Eclipsing binaries with candidate CP stars
- Short Name:
- J/A+A/324/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometry in the Geneva systems and radial velocities are used to determine the fundamental parameters of three eclipsing binaries, two of which having been classified as chemically peculiar and the third having relatively narrow lines. For a description of the Geneva photometric system, see e.g. <GCPD/13>
- ID:
- ivo://CDS.VizieR/J/A+A/506/491
- Title:
- Eclipsing binary candidates in Corot-IRa01 field
- Short Name:
- J/A+A/506/491
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. We present the list of planetary transit candidates detected in the first field observed by CoRoT, IRa01, the initial run toward the Galactic anticenter, which lasted for 60 days. We analysed 3898 sources in the coloured bands and 5974 in the monochromatic band. Instrumental noise and stellar variability were taken into account using detrending tools before applying various transit search algorithms.
- ID:
- ivo://CDS.VizieR/J/A+A/297/359
- Title:
- Eclipsing binary HU Tauri
- Short Name:
- J/A+A/297/359
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The photometric elements of HU Tauri are derived from an analysis of its blue and visual light curves using the Wilson and Devinney (1971, ApJ 166, 605) light curve synthesis method. Combining the photometric elements and spectroscopic orbital elements the absolute dimensions of the system are derived.
- ID:
- ivo://CDS.VizieR/J/ApJ/831/L6
- Title:
- Eclipsing binary parallaxes with Gaia data
- Short Name:
- J/ApJ/831/L6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We test the parallaxes reported in the Gaia first data release using the sample of eclipsing binaries with accurate, empirical distances from Stassun & Torres (2016, arXiv:1609.02579). We find an average offset of -0.25+/-0.05mas in the sense of the Gaia parallaxes being too small (i.e., the distances too long). The offset does not depend strongly on obvious parameters such as color or brightness. However, we find with high confidence that the offset may depend on ecliptic latitude: the mean offset is -0.38+/-0.06mas in the ecliptic north and -0.05+/-0.09mas in the ecliptic south. The ecliptic latitude dependence may also be represented by the linear relation, {Delta}{pi}~-0.22(+/-0.05)-0.003(+/-0.001)x{beta}mas ({beta} in degrees). Finally, there is a possible dependence of the parallax offset on distance, with the offset becoming negligible for {pi}<~1mas; we discuss whether this could be caused by a systematic error in the eclipsing binary distance scale, and reject this interpretation as unlikely.
- ID:
- ivo://CDS.VizieR/J/other/IBVS/5592
- Title:
- Eclipsing binary stars photoelectric minima
- Short Name:
- J/other/IBVS/559
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- All observations were conducted in Tashkent, Uzbekistan from an urban yard under moderate light pollution. 28cm Schmidt-Cassegrain, 2640mm focal length. German equatorial mount.
- ID:
- ivo://CDS.VizieR/J/A+A/557/A119
- Title:
- Eclipsing binary system LL Aquarii
- Short Name:
- J/A+A/557/A119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The eclipsing binary LL Aqr consists of two late-type stars in an eccentric orbit with a period of 20.17d. We use an extensive light curve from the SuperWASP survey augmented by published radial velocities and UBV light curves to measure the physical properties of the system. The primary star has a mass of 1.167+/-0.009M_{sun}_ and a radius of 1.305+/-0.007R_{sun}_. The secondary star is an analogue of the Sun, with a mass and radius of 1.014+/-0.006M_{sun}_ and 0.990+/-0.008R_{sun}_ respectively. The system shows no signs of stellar activity: the upper limit on spot-induced rotational modulation is 3mmag, it is slowly rotating, has not been detected at X-ray wavelengths, and the calcium H and K lines exhibit no emission. Theoretical stellar models provide a good match to its properties for a sub-solar metal abundance of Z=0.008 and an age of 2.5Gyr. Most low-mass eclipsing binary systems are found to have radii larger than expected from theoretical predictions, blamed on tidally-enhanced magnetic fields in these short- period systems. The properties of LL Aqr support this scenario: it exhibits negligible tidal effects, shows no signs of magnetic activity, and matches theoretical models well.