- ID:
- ivo://CDS.VizieR/J/A+AS/130/223
- Title:
- Multiplicity among peculiar A stars I.
- Short Name:
- J/A+AS/130/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial velocities measured with the Coravel scanner are used to determine the orbits of two Ap stars and of two Am stars. The Ap stars HD 8441 appears to be a triple system (though of SB1 type), while improved orbital elements and masses are given for the classical Ap star beta CrB. Both Am stars HD 43478 and HD 93961 are SB2 binaries, and the fundamental elements of the former can be known thanks to its eclipsing nature.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/441/2316
- Title:
- 10 nearby solar-type dwarfs RV curves
- Short Name:
- J/MNRAS/441/2316
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Several nearby solar-type dwarfs with variable radial velocity were monitored to find their spectroscopic orbits. Orbital elements of HIP 179, 1989, 2981, 5276, 6439, 11218, 21443, 96434 are determined, as well as tentative orbits for HIP 28678 and 41214. We discuss each of those objects. Three of the four double-lined binaries are twins with nearly equal components. All four orbits with periods shorter than 10d are circular, the remaining orbits are eccentric.
- ID:
- ivo://CDS.VizieR/J/AJ/144/7
- Title:
- Near-IR imaging of Hipparcos astrometric binaries
- Short Name:
- J/AJ/144/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A subset of 51 Hipparcos astrometric binaries among FG dwarfs within 67pc has been surveyed with the Near-Infrared Coronagraphic Imager adaptive optics system at Gemini-S, directly resolving for the first time 17 subarcsecond companions and 7 wider ones. Using these data together with published speckle interferometry of 57 stars, we compare the statistics of resolved astrometric companions with those of a simulated binary population. The fraction of resolved companions is slightly lower than expected from binary statistics. About 10% of astrometric companions could be "dark" (white dwarfs and close pairs of late M-dwarfs). To our surprise, several binaries are found with companions too wide to explain the acceleration. Re-analysis of selected intermediate astrometric data shows that some acceleration solutions in the original Hipparcos catalog are spurious.
- ID:
- ivo://CDS.VizieR/J/A+A/375/130
- Title:
- New PMS spectroscopic binaries in Orion
- Short Name:
- J/A+A/375/130
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 2 contains the heliocentric radial velocity data versus Heliocentric Julian Day for six X-ray selected double-lined spectroscopic binaries in Orion. Of these, the four systems RXJ 0529.4+0041, RXJ 0530.7-0434, RXJ 0532.1-0732, and RXJ 0541.4-0324 are pre-main sequence systems. Table 3 contains the radial velocity data for the third components of the spectroscopic systems RXJ 0441.0-0839, RXJ 0529.4+0041, and RXJ 0532.1-0732
- ID:
- ivo://CDS.VizieR/J/PAZh/24/343
- Title:
- New spectroscopic components
- Short Name:
- J/PAZh/24/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on the correlation radial-velocity measurement, we discovered new spectroscopic subsystems in the components of six visual multiple stars and determined the elements of their spectroscopic orbits.
- ID:
- ivo://CDS.VizieR/J/A+A/600/L9
- Title:
- NGC 1514 and LoTr 5 radial velocity curves
- Short Name:
- J/A+A/600/L9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The importance of long-period binaries on the formation and evolution of planetary nebulae is still rather poorly understood, in part due to the lack of central star systems known to comprise such long-period binaries. Here, we report on the latest results from the on-going Mercator-HERMES survey for variability in the central stars of planetary nebulae. We present a study of the central stars of NGC 1514, BD+30 623, the spectrum of which shows features associated with a hot nebular progenitor as well as a possible A-type companion. Cross-correlation of high-resolution HERMES spectra against synthetic spectra shows the system to be a highly eccentric (e~0.5), double-lined binary with a period of ~3300 days. Previous studies indicated that the cool component might be a Horizontal Branch star of mass ~0.55M_{sun}_ but the observed radial velocity amplitudes rule out such a low mass. Assuming the nebular symmetry axis and binary orbital plane are perpendicular, the data are more consistent with a post-main-sequence star ascending towards the Giant Branch. We also present the continued monitoring of the central star of LoTr 5, HD 112313, which has now completed one full cycle, allowing the orbital period (P~2700-days) and eccentricity (e~0.3) to be derived. To date, the orbital periods of BD+30 623 and HD 112313 are the longest to have been measured spectroscopically in the central stars of planetary nebulae. Furthermore, these systems, along with BD+33 2642, comprise the only spectroscopic wide-binary central stars currently known.
- ID:
- ivo://CDS.VizieR/J/A+A/649/A178
- Title:
- NGC6791 V604 Lyr disentangled component spectra
- Short Name:
- J/A+A/649/A178
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Models of stellar structure and evolution can be constrained using accurate measurements of the parameters of eclipsing binary members of open clusters. Multiple binary stars provide the means to tighten the constraints, and in turn, to improve the precision and accuracy of the age estimate of the host cluster. In the previous two papers of this series, we demonstrated the use of measurements of multiple eclipsing binaries in the old open cluster NGC6791 to set tighter constraints on the properties of stellar models than was previously possible, thereby improving both the accuracy and precision of the cluster age. We identify and measure the properties of a non-eclipsing cluster member, V56 (Cl* NGC 6791 KR V56), in NGC 6791 and demonstrate how this provides additional model constraints that support and strengthen our previous findings. We analyse multi-epoch spectra of V56 from FLAMES in conjunction with the existing photometry and measurements of eclipsing binaries in NGC6971. The parameters of the V56 components are found to be Mp=1.103+/-0.008M_{sun}_ and Ms=0.974+/-0.007M_{sun}_, Rp=1.764+/-0.099R_{sun}_ and Rs=1.045+/-0.057R_{sun}_, Teff,p=5447+/-125K and Teff,s=5552+/-125K, and surface [Fe/H]=+0.29+/-0.06 assuming that they have the same abundance. The derived properties strengthen our previous best estimate of the cluster age of 8.3+/-0.3Gyr and the mass of stars on the lower RGB, M_RGB_=1.15+/-0.02M_{sun}_ for NGC 6791. These numbers therefore continue to serve as verification points for other methods of age and mass measures, such as asteroseismology.
- ID:
- ivo://CDS.VizieR/J/ApJ/629/507
- Title:
- Observed orbital eccentricities for 391 binaries
- Short Name:
- J/ApJ/629/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For 391 spectroscopic and visual binaries with known orbital elements and having B0-F0 IV or V primaries, we collected the derived eccentricities. As has been found by others, those binaries with periods of a few days have been circularized. However, those with periods up to about 1000 or more days show reduced eccentricities that asymptotically approach a mean value of 0.5 for the longest periods. For those binaries with periods greater than 1000 days their distribution of eccentricities is flat from 0 to nearly 1, indicating that in the formation of binaries there is no preferential eccentricity. The binaries with intermediate periods (10-100 days) lack highly eccentric orbits.
- ID:
- ivo://CDS.VizieR/J/A+A/598/A84
- Title:
- OB-type spectroscopic binaries
- Short Name:
- J/A+A/598/A84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Massive binaries play a crucial role in the Universe. Knowing the distributions of their orbital parameters is important for a wide range of topics from stellar feedback to binary evolution channels and from the distribution of supernova types to gravitational wave progenitors, yet no direct measurements exist outside the Milky Way. The Tarantula Massive Binary Monitoring project was designed to help fill this gap by obtaining multi-epoch radial velocity (RV) monitoring of 102 massive binaries in the 30 Doradus region. In this paper we analyze 32 FLAMES/GIRAFFE observations of 93 O- and 7 B-type binaries. We performed a Fourier analysis and obtained orbital solutions for 82 systems: 51 single-lined (SB1) and 31 double-lined (SB2) spectroscopic binaries. Results. Overall, the binary fraction and orbital properties across the 30 Doradus region are found to be similar to existing Galactic samples. This indicates that within these domains environmental effects are of second order in shaping the properties of massive binary systems. A small difference is found in the distribution of orbital periods, which is slightly flatter (in log space) in 30 Doradus than in the Galaxy, although this may be compatible within error estimates and differences in the fitting methodology. Also, orbital periods in 30 Doradus can be as short as 1.1d, somewhat shorter than seen in Galactic samples. Equal mass binaries (q>0.95) in 30 Doradus are all found outside NGC 2070, the central association that surrounds R136a, the very young and massive cluster at 30 Doradus's core. Most of the differences, albeit small, are compatible with expectations from binary evolution. One outstanding exception, however, is the fact that earlier spectral types (O2-O7) tend to have shorter orbital periods than later spectral types (O9.2-O9.7). Our results point to a relative universality of the incidence rate of massive binaries and their orbital properties in the metallicity range from solar (Z_{sun}_) to about half solar. This provides the first direct constraints on massive binary properties in massive star-forming galaxies at the Universe's peak of star formation at redshifts z~1 to 2 which are estimated to have Z~0.5 Z_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/545/A121
- Title:
- {omicron} Puppis spectra
- Short Name:
- J/A+A/545/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The spectrum of the Be star omi Pup is shown to vary periodically with a period of 28.9 days.
