- ID:
- ivo://CDS.VizieR/J/A+A/393/965
- Title:
- Intrinsic frequencies of slowly pulsating B stars
- Short Name:
- J/A+A/393/965
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of detailed frequency analyses of a sample of thirteen confirmed slowly pulsating B stars. Our analysis is based on a combination of elaborate photometric and spectroscopic data-sets. The original sample consists of a mixture of five confirmed slowly pulsating B stars and twelve candidate slowly pulsating B stars discovered thanks to the photometric measurements of the HIPPARCOS satellite. HD 55522 and HD 131120 turn out to be chemically peculiar stars. HD 169978 and HD 69144 are two ellipsoidal variables for which no intrinsic variability is found. At least nine of the thirteen studied slowly pulsating B stars are multi-periodic. We here present the observed amplitudes, phases and their corresponding standard errors of the variations with the accepted intrinsic frequencies in the first three normalised velocity moments of the SiII 413.0nm line profiles, in the seven filters of the Geneva photometric system, and in the Hp filter of the HIPPARCOS photometric system. They are determined by fitting the data with a superposition of sinusoidal models with reference epoch HJD=2450000. For the higher order moments, the appropriate interaction terms are also taken into account (see Mathias et al., 1994A&A...283..813M). We use the same notations as in Aerts (1996A&A...314..115A) and Aerts (2000, Cat. <J/A+A/361/245>) for the amplitudes of respectively the velocity moments and the variations in the Geneva data.
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- ID:
- ivo://CDS.VizieR/J/A+A/446/583
- Title:
- Journal of all RVs of eps Per primary
- Short Name:
- J/A+A/446/583
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A detailed analysis of a large collection of electronic spectra from three observatories, together with radial velocities published earlier, were used to derive a new ephemeris and improved orbital elements for the eps Per binary. Observations covering a time interval of about 37000-days (101.3-years) can be reconciled with a constant orbital period of (14.0691+/-0.00004)-days. The high orbital eccentricity of 0.555+/-0.009 was also confirmed. New spectral observations confirm that there is a periodic variation of the systemic velocity. Together with new evidence from astrometric observations (also analyzed here), they confirm the existence of a third body in the system with an orbital period of about 9600-days (26.3-years), rather than 4156-days, as reported earlier. Application of the disentangling technique to the H alpha spectra with good S/N ratios did not allow detection of spectral lines of either the secondary or tertiary components. For plausible inclinations between 30 and 90 {deg}, the observed mass function implies a mass of the secondary M_2_=0.85-1.77M_{sun}_, if a primary mass is adopted of (13.5+/-2.0)M_{sun}_. Attempts to detect the third body via interferometric observations should continue in spite of this first negative result.
- ID:
- ivo://CDS.VizieR/J/AJ/142/160
- Title:
- Kepler Mission. II. Eclipsing binaries in DR2
- Short Name:
- J/AJ/142/160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Kepler Mission (launched in 2009 March) provides nearly continuous monitoring of ~156000 objects with unprecedented photometric precision. Coincident with the first data release, we presented a catalog of 1879 eclipsing binary systems identified within the 115deg^2^ Kepler field of view (FOV). Here, we provide an updated catalog from paper I (Prsa et al. 2011, Cat. J/AJ/141/83) augmented with the second Kepler data release which increases the baseline nearly fourfold to 125 days. Three hundred and eighty-six new systems have been added, ephemerides and principal parameters have been recomputed. We have removed 42 previously cataloged systems that are now clearly recognized as short-period pulsating variables and another 58 blended systems where we have determined that the Kepler target object is not itself the eclipsing binary. A number of interesting objects are identified. We present several exemplary cases: four eclipsing binaries that exhibit extra (tertiary) eclipse events; and eight systems that show clear eclipse timing variations indicative of the presence of additional bodies bound in the system. We have updated the period and galactic latitude distribution diagrams. With these changes, the total number of identified eclipsing binary systems in the Kepler FOV has increased to 2165, 1.4% of the Kepler target stars.
- ID:
- ivo://CDS.VizieR/J/A+A/648/A113
- Title:
- Kepler red giants in eclipsing binaries RVs
- Short Name:
- J/A+A/648/A113
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Eclipsing binaries (EBs) are unique targets for measuring accurate stellar properties and constraining stellar evolution models. In particular, it is possible to measure masses and radii at the few percent level for both components of a double-lined spectroscopic EB (SB2-EB). On the one hand, detached EBs hosting at least one star with detectable solar-like oscillations constitute ideal test objects to verify the ability of ensemble asteroseismology to derive stellar properties. On the other hand, the oscillations and surface activity of stars that belong to EBs offer unique information about the evolution of binary systems. This paper builds upon previous works dedicated to red giant stars (RG) in EBs; so far 20 known systems have been discovered by the NASA Kepler mission. We report the discovery of 16 RGs in EBs, which are also from the Kepler data, leading to a total of 36 confirmed RG stars in EBs from the original Kepler mission. This new sample includes three SB2-EBs with oscillations, resulting in a total of 14 known SB2-EBs with an oscillating RG component. This sample also includes six close systems in which the RG display a clear surface activity and complete oscillation suppression. Based on dedicated high-resolution spectroscopic observations (Apache Point Observatory, Observatoire de Haute Provence), we focus on three main aspects. Firstly, from the extended sample of 14 SB2-EBs, we confirm that the simple application of the asteroseismic scaling relations to RGs overestimates masses and radii of RGs by about 15% and 5 %. This bias can be reduced by employing either new asteroseismic reference values for RGs or model-based corrections of the asteroseismic parameters. Secondly, we confirm that close binarity leads to a high level of photometric modulation (up to 10%) and a suppression of solar-like oscillations. In particular, we show that it reduces the lifetime of radial modes by a factor of up to 10. Thirdly, we use our 16 new systems to complement previous observational studies that aimed to constrain tidal dissipation in interacting binaries. We confirm the important role of the equilibrium tide in binary evolution, but we also identify systems with circular orbits despite relatively young ages, which suggests the need to explore complementary tidal dissipation mechanisms in the future. Finally, as a by-product, we report the measurements of mass, radius, and age of three M-dwarf companion stars.
- ID:
- ivo://CDS.VizieR/J/A+A/631/A126
- Title:
- KIC 9832227 light curves
- Short Name:
- J/A+A/631/A126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We revisit the issue of period variation of the recently claimed red nova precursor candidate KIC 9832227. By using the data gathered during the main mission of the Kepler satellite, and data collected by ground-based wide-field surveys and other monitoring programs (such as ASAS-SN), we find that the currently available timing data strongly support a model consisting of the known W UMa binary and a distant low-mass companion with an orbital period of ~13.5 years. The period of the W UMa component exhibits a linear period decrease at a rate of (1.10+/-0.05)x10^-6^ days per year, within the range of many other similar systems. This rate of decrease is several orders of magnitude lower than that of V1309 Sco, the first (and so far the only) well-established binary precursor of a nova observed a few years before the outburst. The high-fidelity fit of the timing data and the conformity of the derived minimum mass of (0.38+/-0.02)M_{sun}_ of the outer companion from these data with the limit posed by the spectroscopic non-detection of this component are in agreement with the suggested hierarchical nature of this system.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A56
- Title:
- KIC 11285625: list of detected frequencies
- Short Name:
- J/A+A/556/A56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first binary modelling results for the pulsating eclipsing binary KIC 11285625, discovered by the Kepler mission. An automated method to disentangle the pulsation spectrum and the orbital variability in high quality light curves, was developed and applied. The goal was to obtain accurate orbital and component properties, in combination with essential information derived from spectroscopy. A binary model for KIC 11285625 was obtained, using a combined analysis of high-quality space-based Kepler light curves and ground-based high-resolution HERMES echelle spectra. The binary model was used to separate the pulsation characteristics from the orbital variability in the Kepler light curve in an iterative way. We used an automated procedure to perform this task, based on the JKTEBOP binary modelling code, and adapted codes for frequency analysis and prewhitening of periodic signals. Using a disentangling technique applied to the composite HERMES spectra, we obtained a higher signal-to-noise mean component spectrum for both the primary and the secondary. A model grid search method for fitting synthetic spectra was used for fundamental parameter determination for both components. Accurate orbital and component properties of KIC 11285625 were derived, and we have obtained the pulsation spectrum of the gamma Dor pulsator in the system. Detailed analysis of the pulsation spectrum revealed amplitude modulation on a time scale of a hundred days, and strong indications of frequency splittings at both the orbital frequency, and the rotational frequency derived from spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+A/563/A59
- Title:
- KIC 3858884: list of pulsation frequencies
- Short Name:
- J/A+A/563/A59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Analysis of eclipsing binaries containing non-radial pulsators allows i) combining two different and independent sources of information on the internal structure and evolutionary status of the components and ii) studying the effects of tidal forces on pulsations. KIC 3858884 is a bright Kepler target whose light curve shows deep eclipses, complex pulsation patterns with pulsation frequencies typical of delta Sct, and a highly eccentric orbit. We present the result of the analysis of Kepler photometry and of high resolution phase-resolved spectroscopy. Spectroscopy yielded both the radial velocity curves and, after spectral disentangling, the primary-component effective temperature and metallicity, and line-of-sight projected rotational velocities. The Kepler light curve was analyzed with an iterative procedure that was devised to disentangle eclipses from pulsations and takes the visibility of the pulsating star into account during eclipses. The search for the best set of binary parameters was performed by combining the synthetic light curve models with a genetic minimization algorithm, which yielded a robust and accurate determination of the system parameters. The binary components have very similar masses (1.88 and 1.86M_{sun}_) and effective temperatures (6800 and 6600K), but different radii (3.45 and 3.05R_{sun}_). The comparison with the theoretical models showed a somewhat different evolutionary status of the components and the need to introduce overshooting in the models. The pulsation analysis indicates the hybrid nature of the pulsating (secondary) component, where the corresponding high order g-modes might be excited by an intrinsic mechanism or by tidal forces.
- ID:
- ivo://CDS.VizieR/J/ApJ/697/1103
- Title:
- Kinematics of Orion Nebula Cluster
- Short Name:
- J/ApJ/697/1103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a kinematic study of the Orion Nebula Cluster (ONC) based upon RVs measured by multifiber echelle spectroscopy at the 6.5m MMT and Magellan telescopes. Velocities are reported for 1613 stars, with multi-epoch data for 727 objects as part of our continuing effort to detect and analyze spectroscopic binaries (SBs). We confirm and extend the results of Furesz et al. (2008, Cat. J/ApJ/676/1109), showing that the ONC is not relaxed, consistent with its youth, and that the stars generally follow the position-velocity structure of the moderate density gas in the region, traced by ^13^CO. The additional RVs we have measured enable us to probe some discrepancies between stellar and gaseous structure which can be attributed to binary motion and the inclusion of nonmembers in our kinematic sample. Our multi-epoch data allow us to identify 89 SBs; more will be found as we continue monitoring. Our results reinforce the idea that the ONC is a cluster in formation, and thus provide a valuable testing ground for theory.
- ID:
- ivo://CDS.VizieR/J/MNRAS/357/497
- Title:
- Kinematics of W UMa-type binaries
- Short Name:
- J/MNRAS/357/497
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The kinematics of 129 W Ursae Majoris type binaries (W UMas) were studied. The sample is heterogeneous with different orbits and physically different components from F to K spectral-type main-sequence stars. The computed U, V, W space velocities indicate that the sample is also heterogeneous in velocity space.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/4641
- Title:
- LAMOST DR5 White dwarf-main sequence binaries
- Short Name:
- J/MNRAS/477/4641
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the data release (DR) 5 catalogue of white dwarf-main sequence (WDMS) binaries from the Large sky Area Multi-Object fibre Spectroscopic Telescope (LAMOST). The catalogue contains 876 WDMS binaries, of which 757 are additions to our previous LAMOST DR1 sample and 357 are systems that have not been published before. We also describe a LAMOST-dedicated survey that aims at obtaining spectra of photometrically selected WDMS binaries from the Sloan Digital Sky Survey (SDSS) that are expected to contain cool white dwarfs and/or early-type M dwarf companions. This is a population under-represented in previous SDSS WDMS binary catalogues. We determine the stellar parameters (white dwarf effective temperatures, surface gravities and masses, and M dwarf spectral types) of the LAMOST DR5 WDMS binaries and make use of the parameter distributions to analyse the properties of the sample. We find that, despite our efforts, systems containing cool white dwarfs remain under-represented. Moreover, we make use of LAMOST DR5 and SDSS DR14 (when available) spectra to measure the NaI {lambda}{lambda} 8183.27, 8194.81 absorption doublet and/or H{alpha} emission radial velocities of our systems. This allows identifying 128 binaries displaying significant radial velocity variations, 76 of which are new. Finally, we cross-match our catalogue with the Catalina Surveys and identify 57 systems displaying light-curve variations. These include 16 eclipsing systems, two of which are new, and nine binaries that are new eclipsing candidates. We calculate periodograms from the photometric data and measure (estimate) the orbital periods of 30 (15) WDMS binaries.
