- ID:
- ivo://CDS.VizieR/J/AcA/58/405
- Title:
- ASAS eclipsing binaries with RASS counterpart
- Short Name:
- J/AcA/58/405
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- ROSAT All Sky Survey (RASS). The combination results in 836 eclipsing binaries that display coronal activity and is the largest sample of active binary stars assembled to date. By using the (V-I) colors of the ASAS eclipsing binary catalog, we are able to determine the distances and thus bolometric luminosities for the majority of eclipsing binaries that display significant stellar activity.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/526/A29
- Title:
- ASAS low-mass eclipsing binaries light curves
- Short Name:
- J/A+A/526/A29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our detailed spectroscopic and photometric analysis of two previously unknown <1M_{sun}_ detached eclipsing binaries: ASAS J045304-0700.4 and ASAS J082552-1622.8.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/3474
- Title:
- ASAS, NSVS, and LINEAR detached eclipsing binaries
- Short Name:
- J/MNRAS/453/3474
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Eclipsing binaries provide a unique opportunity to measure fundamental properties of stars. With the advent of all-sky surveys, thousands of eclipsing binaries have been reported, yet their light curves are not fully exploited. The goal of this work is to make use of the eclipsing binary light curves delivered by all-sky surveys. We attempt to extract physical parameters of the binary systems from their light curves and colour. Inspired by the work of Devor et al., we use the Detached Eclipsing Binary Light curve fitter (DEBIL) and the Method for Eclipsing Component Identification (MECI) to derive basic properties of the binary systems reported by the All Sky Automated Survey, the Northern Sky Variability Survey, and the Lincoln Near Earth Asteroids Research. We derive the mass, fractional radius, and age for 783 binary systems. We report a subsample of eccentric systems and compare their properties to the tidal circularization theory. With MECI, we are able to estimate the distance of the eclipsing binary systems and use them to probe the structure of the Milky Way. Following the approach of Devor et al., we demonstrate that DEBIL and MECI are instrumental to investigate eclipsing binary light curves in the era of all-sky surveys, and provide estimates of stellar parameters of both binary components without spectroscopic information.
- ID:
- ivo://CDS.VizieR/J/other/NewA/51.1
- Title:
- AS CrB BVRI light curves
- Short Name:
- J/other/NewA/51.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first high-precision BVRI light curves of the eclipsing binary AS CrB were presented and were analyzed by the 2015 version of the W-D code. It is found that AS CrB is an extreme mass-ratio, deep contact binary with a fill-out factor of f=59.6+/-2.5% and a mass ratio of q=0.172+/-0.008q=0.172+/-0.008. Based on the photometric solution and the Dartmouth isochrones model, the masses, radii, and luminosities of the components are estimated as follows: M_1_=1.25+/-0.15M_{sun}_, M_1_=1.25+/-0.15M_{sun}_, M_2_=0.21+/-0.06M_{sun}_, M_2_=0.21+/-0.06M_{sun}_, R_1_=1.40+/-0.07R_{sun}_, R_1_=1.40+/-0.07R_{sun}_, R_2_=0.67+/-0.04R_{sun}_, R_2_=0.67+/-0.04R_{sun}_, L_1_=3.2+/-0.2L_{sun}_, L_1_=3.2+/-0.2L_{sun}_, and L_2_=0.72+/-0.04L_{sun}_, L_2_=0.72+/-0.04L_{sun}_, with an estimated distance 459+/-42pc. These uncertainties mainly come from the errors of the color used to estimate the temperature of the primary star. By investigating all of the available times of light minima, it is found that the Observed-Calculated [(O-C)(O-C)] curve shows a long-term period increase, with a rate of dP/dt=+(3.46+/-0.01)x10^-7^dP/dt=+(3.46+/-0.01)x10^-7^day/year. As an extreme mass-ratio contact binary, AS CrB may merge into a single star, such as an FK Com-type star or a blue straggler, because of the orbital instability.
- ID:
- ivo://CDS.VizieR/J/ApJS/226/21
- Title:
- ASTEP catalog of EB* and variable stars
- Short Name:
- J/ApJS/226/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used the large photometric database of the ASTEP program, whose primary goal was to detect exoplanets in the southern hemisphere from Antarctica, to search for eclipsing binaries (EcBs) and variable stars. 673 EcBs and 1166 variable stars were detected, including 31 previously known stars. The resulting online catalogs give the identification, the classification, the period, and the depth or semi-amplitude of each star. Data and light curves for each object are available at http://astep-vo.oca.eu/.
- ID:
- ivo://CDS.VizieR/J/A+A/536/A27
- Title:
- AX Per UBVRI photometry
- Short Name:
- J/A+A/536/A27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- AX Per is an eclipsing symbiotic binary. During active phases, deep narrow minima are observed in its light curve, and the ionization structure in the binary changes significantly. From ~2007.5, AX Per entered a new active phase. We aim to derive the ionization structure in the binary and its changes during the recent active phase. We used optical high- and low-resolution spectroscopy and UBVRcIc photometry. We modeled the SED in the optical and broad wings of the H alpha line profile during the 2007-10 higher level of the AX Per activity. After 10 orbital cycles (~18.6 years), we again measured the eclipse of the hot component by its giant companion in the light curve. We derived a radius of 27+/-2R_{sun}_ for the eclipsed object and 115+/-2R_{sun}_ for the eclipsing cool giant. The new active phase was connected with a significant enhancement of the hot star wind. From quiescence to activity, the mass-loss rate increased from ~9E-8 to ~3E-6M_{sun}_/yr, respectively. The wind causes the emission of the He++ zone, located in the vicinity of the hot star, and also is the reason for the fraction of the [OIII] zone at farther distances. Simultaneously, we identified a variable optically thick warm (T_eff_~6000K) source that contributes markedly to the composite spectrum. The source was located at the hot star's equator and has the form of a flared disk, whose outer rim simulates the warm photosphere. The formation of the neutral disk-like zone around the accretor during the active phase was connected with its enhanced wind. It is probable that this connection represents a common origin of the warm pseudophotospheres that are indicated during the active phases of symbiotic stars.
- ID:
- ivo://CDS.VizieR/J/A+A/580/A21
- Title:
- BEER analysis of CoRoT light curves
- Short Name:
- J/A+A/580/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The BEER algorithm, introduced by Faigler & Mazeh (2011MNRAS.415.3921F), searches stellar lightcurves for the BEaming, Ellipsoidal, and Reflection (BEER) photometric modulations that are caused by a short-period companion. These three effects are typically of very low amplitude, and can mainly be detected in lightcurves from space-based photometers. Unlike eclipsing binaries, these effects are not limited to edge-on inclinations. Applying the algorithm to wide-field photometric surveys such as CoRoT and Kepler offers an opportunity to better understand the statistical properties of short-period binaries. It also widens the window for detecting intrinsically rare systems, like short-period brown-dwarf and massive- planetary companions to main-sequence stars. Applying the search to the first five long-run center CoRoT fields, we identified 481 non-eclipsing candidates with periodic flux amplitudes of 0.5-87mmag. Optimizing the Anglo-Australian-Telescope pointing coordinates and the AAOmega fiber-allocations with dedicated softwares, we acquired 6-7 medium-resolution spectra of 281 candidates in a seven-night campaign. Analysis of the red-arm AAOmega spectra, which covered the range of 8342-8842{AA}, yielded a radial-velocity precision of ~1 km/s. Spectra containing lines of more than one star were analyzed with the two- dimensional correlation algorithm TODCOR. The measured radial velocities confirmed the binarity of seventy of the BEER candidates, 45 single-line binaries, 18 double-line binaries, and 7 diluted binaries. We show that red giants introduce a major source of false candidates and demonstrate a way to improve BEER's performance in extracting higher fidelity samples from future searches of CoRoT lightcurves. The periods of the confirmed binaries span a range of 0.3-10days and show a rise in the number of binaries per logP bin toward longer periods. The estimated mass ratios of the double-line binaries and the mass ratios assigned to the single-line binaries, assuming an isotropic inclination distribution, span a range of 0.03-1. On the low-mass end we have detected two brown-dwarf candidates on a ~1day period orbit. This is the first time non-eclipsing beaming binaries are detected in CoRoT data, and we estimate that ~300 such binaries can be detected in the CoRoT long-run lightcurves.
- ID:
- ivo://CDS.VizieR/J/AJ/151/110
- Title:
- BEST-II catalog of variables: CoRoT SRc02 field
- Short Name:
- J/AJ/151/110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Time-series photometry of the CoRoT field SRc02 was obtained by the Berlin Exoplanet Search Telescope II (BEST II) in 2009. The main aim was to conduct a ground-based follow-up of the CoRoT field in order to detect variable stars with better spatial resolution than what can be achieved with the CoRoT Space Telescope. A total of 1846 variable stars were detected, of which only 30 have been previously known. For nine eclipsing binaries the stellar parameters were determined by modeling their light curves.
- ID:
- ivo://CDS.VizieR/J/AJ/156/204
- Title:
- BEST-II catalog of variables. III. Puppis field
- Short Name:
- J/AJ/156/204
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Berlin Exoplanet Search Telescope II (BEST II) is a ground-based, small aperture, wide-angle telescope used to search for stellar light variations in the southern hemisphere. We report the results of a monitoring campaign observing a field in the Puppis constellation in late 2011/early 2012. Light curves were obtained for 130472 stars, out of which we identify 2169 variables, including 1829 newly discovered, 26 previously known, and 314 suspected variable stars. We determine periods and variability class for two previously known, but only suspected to be, variable stars. For eight individual eclipsing binary stars, including the two previously known but unclassified binaries, the system parameters were derived at the epoch of the observation by modeling the light curves. Eventually, in a catalog for all variable stars, we present coordinates, magnitude, and elements of light variations, e.g., epoch, period, amplitude, type, and light curves. This catalog concludes the BEST/BEST II project.
- ID:
- ivo://CDS.VizieR/J/AJ/146/136
- Title:
- BEST-II catalog of variables. I. Southern fields
- Short Name:
- J/AJ/146/136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A photometric survey of three southern target fields with BEST II yielded the detection of 2406 previously unknown variable stars and an additional 617 stars with suspected variability. This study presents a catalog including their coordinates, magnitudes, light curves, ephemerides, amplitudes, and type of variability. In addition, the variability of 17 known objects is confirmed, thus validating the results. The catalog contains a number of known and new variables that are of interest for further astrophysical investigations, in order to, e.g., search for additional bodies in eclipsing binary systems, or to test stellar interior models. Altogether, 209070 stars were monitored with BEST II during a total of 128 nights in 2009/2010. The overall variability fraction of 1.2%-1.5% in these target fields is well comparable to similar ground-based photometric surveys. Within the main magnitude range of R{isin}[11, 17], we identify 0.67(3)% of all stars to be eclipsing binaries, which indicates a completeness of about one third for this particular type in comparison to space surveys.
