- ID:
- ivo://CDS.VizieR/J/AJ/147/130
- Title:
- Minimum times of 7 eclipsing systems
- Short Name:
- J/AJ/147/130
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The minimum timings of eclipsing binaries V418 Aql, SU Boo, RV CVn, CR Cas, GV Cyg, V432 Per, and BD+42 2782 were collected and analyzed. Their long-term behavior was studied via period analysis, revealing a periodic term in eclipse times. We derived 576 new times of minimum. Hence, to describe the periodic variation, a third-body hypothesis was proposed and the resulting orbital periods are as follows: 70, 7.4, 53, 37, 27, 53, and 18 yr, respectively. For the system V432 Per an additional 9.5 yr variation was also found. The predicted minimum masses of these distant bodies were calculated and their detectability discussed. The light curves of SU Boo and RV CVn were analyzed using the PHOEBE program, resulting in physical parameters of the components. New variable stars in the field of V418 Aql were discovered.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/408/L51
- Title:
- 2M1938+4603 (KIC 9472174) eclipses
- Short Name:
- J/MNRAS/408/L51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 2M1938+4603 (KIC 9472174) displays a spectacular light curve dominated by a strong reflection effect and rather shallow, grazing eclipses. The orbital period is 0.126d, the second longest period yet found for an eclipsing sdB+dM, but still close to the minimum 0.1-d period among such systems. The phase-folded Kepler light curve was used to detrend the orbital effects from the data set. The amplitude spectrum of the residual light curve reveals a rich collection of pulsation peaks spanning frequencies from ~50 to 4500uHz. The presence of a complex pulsation spectrum in both the p- and g-mode regions has never before been reported in a compact pulsator.
- ID:
- ivo://CDS.VizieR/J/MNRAS/382/1073
- Title:
- M/L relation of intermediate-mass stars
- Short Name:
- J/MNRAS/382/1073
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The mass-luminosity relation (MLR) for intermediate-mass stars is based on data on detached main-sequence double-lined eclipsing binaries (DM-DLEB). However, there is a notable difference between the parameters of B0V-G0V components of eclipsing binaries and those of single stars. Single early-type stars are rapid rotators, whereas tidal forces produce synchronous rotation in close binaries and all such pairs are synchronized, so components of close binaries rotate more slowly. As is well known, stellar rotation changes stellar evolution and the global parameters of a star. In this work we collect data on fundamental parameters of stars with masses m>1.5m_{sun}_. They are components of binaries with P>15d and consequently are not synchronized with the orbital periods and presumably are rapid rotators. These stars are believed to evolve similarly with single stars. Modern data on masses, absolute and bolometric luminosities, radii and temperatures of detached main-sequence double-lined eclipsing binary components (i.e. presumably slow rotators) are also collected. Mass-luminosity, mass-temperature and mass-radius relations of close and wide binaries are presented, as well as their Hertzsprung-Russell diagram.
- ID:
- ivo://CDS.VizieR/J/AZh/79/259
- Title:
- Models for Intermediate-Mass Eclipsing Binaries
- Short Name:
- J/AZh/79/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use estimates of ages and abundances made for a set of eclipsing binaries (Kovaleva, 2001, Cat. <J/AZh/78/1104), to re-calculate observational values of radii, effective temperatures and luminosities of these stars for solar abundance ZAMS. Geneva group evolutionary grids of models were used for this recalculation. We also present empirical and semi-empirical (for ZAMS evolutionary stage and solar metallicity) relations between mass and luminosity, temperature and radius.
- ID:
- ivo://CDS.VizieR/J/A+A/655/A4
- Title:
- MONOS II. SB1 Orbital review and analysis
- Short Name:
- J/A+A/655/A4
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Massive stars are a key element to understand the chemical and dynamical evolution of galaxies. Stellar evolution is conditioned by many factors: rotation, mass loss, and interaction with other objects are the most important ones for massive stars. During the first evolutionary stages of stars with initial masses (i.e. M_ZAMS_) in the M_ZAMS_~18-70M_{sum}_ range they are of spectral type O. Given that stars in this mass range spend roughly 90% of their lifetime as O-type stars, establishing the multiplicity frequency and binary properties of O-type stars is crucial for many fields of modern astrophysics. The aim of the MONOS project is to collect information to study Northern Galactic O-type spectroscopic binaries. In this second paper, we tackle the study of the 35 single line spectroscopic binary (SB1) systems identified in the previous paper of the series Maiz Apellaniz et al., (2019, Cat. J/A+A/626/A20) analyze our data, and review the literature on the orbits of the systems. We have measured ~4500 radial velocities for a selection of diagnostic lines for the ~700 spectra of the studied systems in our database, for which we have used two different methods: Gaussian fit for several lines per object and cross-correlation with synthetic spectra computed with the FASTWIND stellar atmospheric code. We have also explored the photometric data delivered by the TESS mission to analyze the light-curve (LC) of the systems extracting 31 of them. We have explored the possible periods with the Lomb-Scargle method and, whenever possible, calculated the orbital solutions using the SBOP&GBART codes. For those systems in which an improved solution was possible we have merged our RVs with those in the literature and calculated a combined solution. As a result of this work, of the 35 SB1 systems identified in MONOS I, we have confirmed 21 systems as SB1 with good orbits, discarded the binary nature of 6 stars (9 Sge, HD 192281, HDE 229232 AB, 68 Cyg, HD 108 and {alpha} Cam), and left 6 stars as inconclusive due to lack of data. The remaining two stars are 15 Mon Aa which has been classified as SB2 and Cyg OB2-22 C for which we find evidence that it is most likely a triple system where the O star is orbiting an eclipsing SB1. We have also recalculated 20 new orbital solutions, including the first spectroscopic orbital solution for V747 Cep. For Cyg OB2-22 C we have obtained new ephemerides but no new orbit.
- ID:
- ivo://CDS.VizieR/J/A+A/626/A20
- Title:
- MONOS. I. Spectral classifications
- Short Name:
- J/A+A/626/A20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Multiplicity in massive stars is a key element to understand the chemical and dynamical evolution of galaxies. Among massive stars, those of O type play a crucial role due to their high masses and short lifetimes. MONOS (Multiplicity Of Northern O-type Spectroscopic systems) is a project designed to collect information and study O-type spectroscopic binaries with {delta}>20{deg}. In this first paper we describe the sample and provide spectral classifications and additional information for objects with previous spectroscopic and/or eclipsing binary orbits. In future papers we will test the validity of previous solutions and calculate new spectroscopic orbits. The spectra in this paper have two sources: the Galactic O-Star Spectroscopic Survey (GOSSS), a project that is obtaining blue-violet R~2500 spectroscopy of thousands of massive stars, and LiLiMaRlin, a library of libraries of high-resolution spectroscopy of massive stars obtained from four different surveys (CAFE-BEANS, OWN, IACOB, and NoMaDS) and additional data from our own observing programs and public archives. We also use lucky images obtained with AstraLux. We present homogeneous spectral classifications for 92 O-type spectroscopic multiple systems and ten optical companions, many of them original.We discuss the visual multiplicity of each system with the support of AstraLux images and additional sources. For eleven O-type objects and for six B-type objects we present their first GOSSS spectral classifications. For two known eclipsing binaries we detect double absorption lines (SB2) or a single moving line (SB1) for the first time, to which we add a third system already reported by us recently. For two previous SB1 systems we detect their SB2 nature for the first time and give their first separate spectral classifications, something we also do for a third object just recently identified as a SB2. We also detect nine new astrometric companions and provide updated information on several others. We emphasize the results for two stars: for {sigma} Ori AaAbB we provide spectral classifications for the three components with a single observation for the first time thanks to a lucky spectroscopy observation obtained close to the Aa,Ab periastron and for {theta}^1^ Ori CaCb we add it to the class of Galactic Of?p stars, raising the number of its members to six. Our sample of O-type spectroscopic binaries contains more triple- or higher-order systems than double systems.
- ID:
- ivo://CDS.VizieR/J/ApJ/859/140
- Title:
- Multi-band magnitudes for W UMa EB* candidates
- Short Name:
- J/ApJ/859/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- W Ursa Majoris (W UMa)-type contact binary systems (CBs) are useful statistical distance indicators because of their large numbers. Here, we establish (orbital) period-luminosity relations (PLRs) in 12 optical to mid-infrared bands (GBVRIJHKsW1W2W3W4) based on 183 nearby W UMa-type CBs with accurate Tycho-Gaia parallaxes. The 1{sigma} dispersion of the PLRs decreases from optical to near- and mid-infrared wavelengths. The minimum scatter, 0.16mag, implies that W UMa-type CBs can be used to recover distances to 7% precision. Applying our newly determined PLRs to 19 open clusters containing W UMa-type CBs demonstrates that the PLR and open cluster CB distance scales are mutually consistent to within 1%. Adopting our PLRs as secondary distance indicators, we compiled a catalog of 55603 CB candidates, of which 80% have distance estimates based on a combination of optical, near-infrared, and mid- infrared photometry. Using Fourier decomposition, 27318 high-probability W UMa-type CBs were selected. The resulting 8% distance accuracy implies that our sample encompasses the largest number of objects with accurate distances within a local volume with a radius of 3kpc available to date. The distribution of W UMa-type CBs in the Galaxy suggests that in different environments, the CB luminosity function may be different: larger numbers of brighter (longer-period) W UMa-type CBs are found in younger environments.
- ID:
- ivo://CDS.VizieR/J/ApJ/728/48
- Title:
- Multicolor eclipse data for 6 new binaries
- Short Name:
- J/ApJ/728/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery and characterization of six new M dwarf eclipsing binary systems. The 12 stars in these eclipsing systems have masses spanning 0.38-0.59M_{sun}_ and orbital periods of 0.6-1.7 days, with typical uncertainties of ~0.3% in mass and ~0.5%-2.0% in radius. Combined with six known systems with high-precision measurements, our results reveal an intriguing trend in the low-mass regime. For stars with M=0.35-0.80M_{sun}_, components in short-period binary systems (P<~1 day; 12 stars) have radii which are inflated by up to 10% ({mu}=4.8+/-1.0%) with respect to evolutionary models for low-mass main-sequence stars, whereas components in longer-period systems (>1.5 days; 12 stars) tend to have smaller radii ({mu}=1.7+/-0.7%).
- ID:
- ivo://CDS.VizieR/J/PAZh/25/764
- Title:
- Multicolor photometry of RY Sct
- Short Name:
- J/PAZh/25/764
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New uvby-{beta} photometry of the unique binary RY Sct is reported. The results were interpreted using the light-curve synthesis method.
- ID:
- ivo://CDS.VizieR/J/A+A/520/A89
- Title:
- Multi-epoch photometry of {delta} Ori
- Short Name:
- J/A+A/520/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For years, {delta} Ori was considered a normal binary with an O9.5 II primary exhibiting apsidal-line advance. However, in 2002 radial-velocity curves of both binary components derived from the IUE and optical spectra using the cross-correlation technique have been published by Harvin et al. (2002ApJ...565.1216H); surprisingly low masses of 11.2 and 5.6M_{sun}_ were obtained. We obtained new spectra in the red spectral region and new UBV photometry. Using all published photometry and radial velocities, we deduced more accurate orbital and apsidal line periods. The main result of this paper is to show that the observed line spectra of {delta} Ori are composed of the lines of the O9.5 II primary and a similarly hot tertiary, while the lines of a cooler B-type secondary are too faint to be detected in the available spectra. The character of the light curve (low-amplitude partial eclipses and a non-negligible scatter of the data) does not allow for a unique light-curve solution. Nevertheless, we show that the assumption of normal primary-component mass and radius corresponding to the O9.5 II classification (25M_{sun}_, 16-17R_{sun}_) leads to consistent parameters for the system.