- ID:
- ivo://CDS.VizieR/J/AJ/153/231
- Title:
- BVR photometry of EPIC 211957146
- Short Name:
- J/AJ/153/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multi-band photometric and spectroscopic study of an over-contact binary system, EPIC211957146. The light curves exhibit a variable O' Connell effect, confirmed from our observational data and the Kepler K2 data. The best photometric solution incorporating a dark spot over the primary component unveils that the system has a low-mass ratio (q~0.17) and a high inclination (i~85{deg}). To confirm the solution and constrain the uncertainty, Monte-Carlo simulations are performed and the results are reported. Based on the O-C diagram analysis, we see that the variable shows a period increase at the rate of dP/dt~1.06x10^-6^days/yr, which is higher than the theoretically predicted value. Presence of a third body having a period of ~16.23years is evident from the O-C diagram. No filled-in effect is observed in the H{alpha} line, while the effect is vividly present in the Na line. From the Kepler K2 data, we found that the primary and secondary minima exhibit an anti-correlated O-C variation followed by an erratic behavior. This is possibly caused by the longitudinal motion of the spot, and hence, we set a lower limit of ~40days for the spot modulation. We also observe a possibly associated photometric difference in the primary depth by comparing our light curves with Kepler K2 normalized light curves. This system has a low-mass ratio and a high fill-out factor, and, theoretically, such a physical configuration would lead to a merger.
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- ID:
- ivo://CDS.VizieR/J/AJ/151/124
- Title:
- BVR photometry of IZ Mon and AR Dra
- Short Name:
- J/AJ/151/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multi-color photometric observations for two neglected near-contact binaries, IZ Mon (P=0.77980^d^) and AR Dra (P=0.67584^d^). By the aid of the updated W-D analysis code, the photometric solutions were deduced from the multi-color light curves (LCs). IZ Mon is a semi-detached binary with a mass ratio of q=0.388(+/-0.002) , while AR Dra is a detached star with a mass ratio of q=0.652(+/-0.002). The asymmetric LCs of IZ Mon were modeled by a hot spot on the secondary's surface, which may be attributed to mass transfer from the primary. Based on all collected eclipse times for two systems, we constructed their timing residual curves. The orbital period for IZ Mon may be continuously decreasing at a rate of dP/dt=-2.06(+/-0.04)days/yr, which may result from mass and angular momentum loss from the central system. For AR Dra, there exists a cyclic variation with a period of P_3_=104.9(+/-2.9)yr due to light-time orbit effect via the presence of the third body, whose mass is more than 0.28(+/-0.02)M_{Sun}_. Finally, two near-contact binaries, IZ Mon and AR Dra, will evolve into contact binaries.
- ID:
- ivo://CDS.VizieR/J/ApJ/750/59
- Title:
- BVR polarimetric observations of {beta} Lyr
- Short Name:
- J/ApJ/750/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from six years of recalibrated and new spectropolarimetric data taken with the University of Wisconsin's Half-Wave Spectropolarimeter and six years of new data taken with the photoelastic modulating polarimeter at the Flower and Cook Observatory of beta Lyrae. Combining these data with polarimetric data from the literature allows us to characterize the intrinsic BVRI polarized light curves. A repeatable discrepancy of 0.245 days (approximately 6hr) between the secondary minima in the total light curve and the polarization curve in the V band, with similar behavior in the other bands, may represent the first direct evidence for an accretion hot spot on the disk edge.
- ID:
- ivo://CDS.VizieR/J/PASJ/65/1
- Title:
- BX Dra BVR differential light curves
- Short Name:
- J/PASJ/65/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New CCD photometric observations of BX Dra were carried out on 26 nights during the period from 2009 April to 2010 June. The long-term photometric behaviors of the system are obtained from detailed studies of the period and light variations, based on historical data and our new observations.
- ID:
- ivo://CDS.VizieR/J/AJ/145/43
- Title:
- CASE. V. Three eclipsing binaries in M4
- Short Name:
- J/AJ/145/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use photometric and spectroscopic observations of the eclipsing binaries V65, V66, and V69 in the field of the globular cluster M4 to derive masses, radii, and luminosities of their components. The orbital periods of these systems are 2.29, 8.11, and 48.19days, respectively. The measured masses of the primary and secondary components (M_p_ and M_s_) are 0.8035+/-0.0086 and 0.6050+/-0.0044M_{sun}_ for V65, 0.7842+/-0.0045 and 0.7443+/-0.0042M_{sun}_ for V66, and 0.7665+/-0.0053 and 0.7278+/-0/0048M_{sun}_ for V69. The measured radii (R_p_ and R_s_) are 1.147+/-0.010 and 0.6110 +/- 0.0092R_{sun}_ for V66, 0.9347+/-0.0048 and 0.8298+/-0.0053R_{sun}_ for V66, and 0.8655+/-0.0097 and 0.8074+/-0.0080R_{sun}_ for V69. The orbits of V65 and V66 are circular, whereas that of V69 has an eccentricity of 0.38. Based on systemic velocities and relative proper motions, we show that all three systems are members of the cluster. We find that the distance to M4 is 1.82+/-0.04kpc-in good agreement with recent estimates based on entirely different methods. We compare the absolute parameters of V66 and V69 with two sets of theoretical isochrones in mass-radius and mass-luminosity diagrams, and for assumed [Fe/H]=-1.20, [{alpha}/Fe]=0.4, and Y=0.25 we find the most probable age of M4 to be between 11.2 and 11.3Gyr. Color-magnitude diagram (CMD) fitting with the same parameters yields an age close to, or slightly in excess of, 12Gyr. However, considering the sources of uncertainty involved in CMD fitting, these two methods of age determination are not discrepant. Age and distance determinations can be further improved when infrared eclipse photometry is obtained.
- ID:
- ivo://CDS.VizieR/J/MNRAS/465/4968
- Title:
- Cataclysmic variables observations
- Short Name:
- J/MNRAS/465/4968
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new time-resolved photometry of 74 cataclysmic variables (CVs), 47 of which are eclipsing. Thirteen of these eclipsing systems are newly discovered. For all 47 eclipsing systems, we show high cadence (1-20s) light curves obtained with the high-speed cameras ULTRACAM and ULTRASPEC. We provide new or refined ephemerides, and supply mid-eclipse times for all observed eclipses. We assess the potential for light-curve modelling of all 47 eclipsing systems to determine their system parameters, finding 20 systems that appear to be suitable for future study. Systems of particular interest include V713 Cep, in which we observed a temporary switching-off of accretion; and ASASSN-14mv and CSS111019:233313-155744, which both have orbital periods well below the CV period minimum. The short orbital periods and light-curve shapes suggest that they may be double degenerate (AM CVn) systems or CVs with evolved donor stars.
- ID:
- ivo://CDS.VizieR/J/ApJS/213/9
- Title:
- Catalina Surveys periodic variable stars
- Short Name:
- J/ApJS/213/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ~47000 periodic variables found during the analysis of 5.4 million variable star candidates within a 20000deg^2^ region covered by the Catalina Surveys Data Release-1 (CSDR1). Combining these variables with type ab RR Lyrae from our previous work, we produce an online catalog containing periods, amplitudes, and classifications for ~61000 periodic variables. By cross-matching these variables with those from prior surveys, we find that >90% of the ~8000 known periodic variables in the survey region are recovered. For these sources, we find excellent agreement between our catalog and prior values of luminosity, period, and amplitude as well as classification. We investigate the rate of confusion between objects classified as contact binaries and type c RR Lyrae (RRc's) based on periods, colors, amplitudes, metallicities, radial velocities, and surface gravities. We find that no more than a few percent of the variables in these classes are misidentified. By deriving distances for this clean sample of ~5500 RRc's, we trace the path of the Sagittarius tidal streams within the Galactic halo. Selecting 146 outer-halo RRc's with SDSS radial velocities, we confirm the presence of a coherent halo structure that is inconsistent with current N-body simulations of the Sagittarius tidal stream. We also find numerous long-period variables that are very likely associated within the Sagittarius tidal stream system. Based on the examination of 31000 contact binary light curves we find evidence for two subgroups exhibiting irregular light curves. One subgroup presents significant variations in mean brightness that are likely due to chromospheric activity. The other subgroup shows stable modulations over more than a thousand days and thereby provides evidence that the O'Connell effect is not due to stellar spots.
- ID:
- ivo://CDS.VizieR/V/121
- Title:
- Catalog of DMS-type eclipsing binaries
- Short Name:
- V/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue contains information about 113 detached main-sequence (DMS) type detached binaries with known photometric and geometric elements.
- ID:
- ivo://CDS.VizieR/V/120
- Title:
- Catalog of early-type contact binaries
- Short Name:
- V/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the first time the early type contact systems were identified as an individual class in M.A. Svechnikov's Catalogue [1] in 1969, which contains 8 systems of this type. The Catalogue of Coch R.H., Plavec M. and Wood F.B. [2] contains 37 systems of the early spectral type. According to Svechnikov's classification [3] a primary component (more massive and hotter) of a CE-system (contact system of early spectral class) has a spectral class earlier than F0-F2 and an orbital period of more than 0.5 day. Usually the spectral class of a primary is earlier than the spectral class of a secondary. Both components fill their Roche-lobes on 90-100%. The following Catalogue of Svechnikov M.A. and Bessonova L.A. [4] contains 38 CE-systems. In 1986 Bondarenko I.I. [5] published the Catalogue of the CE-stars, which contained 83 systems. Physical characteristics of the CE-stars presented in the list of catalogues abovementioned, were obtained by different authors by using different methods of calculation. We propose the Catalogue of the CE-systems with homogeneous absolute physical characteristics, that allows to define accurately general features of this class of binary stars. The comparing of physical characteristics of the CE-systems with other classes` characteristics of binary stars can show the possible evolutionary stages of the CE-systems. The foundation of absolute elements of the CE-systems are the photometric observations (on the whole, the latest multicolour photoelectric, in a few cases photographic and visual observations). The accuracy of modern photometric observations is high, and generally they are processed with the help of reliable computer methods both classical and synthetical methods). But reliable spectral observations (the ray speed curves) are very scarce, especially for both components). We have preferred the spectral class of a primary (usually it is more bright), supposing, that it's spectral class was defined accurately, and photometric and geometrical elements from light curves. All stars from our Catalogue were classified preliminarily as CE-stars by Svechnikov M.A., Istomin L.F. and Grehova O.A. [6]. We have supposed both components fill their Roche-lobes and by using the diagram (q-r[critical]) of Plavec-Kratochvile [7] mass ratio was obtained. The absolute elements were obtained by the approximated method of Svechnikov, which was modernized for CE-stars. Our Catalogue consist of three parts: photometric, geometrical and absolute elements of CE-systems. All stars were divided approximately into two groups: massive (m1>3 solar masses for primary) and less-massive stars (m1<3 solar masses for primary). A Catalogue has a Supplement.
- ID:
- ivo://CDS.VizieR/V/118
- Title:
- Catalog of eclipsing binaries parameters
- Short Name:
- V/118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains information about 44 binaries with known photometric orbit elements and unknown spectroscopic one.
