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- ID:
- ivo://CDS.VizieR/J/MNRAS/479/5491
- Title:
- Absolute parameters of 509 main-sequence stars
- Short Name:
- J/MNRAS/479/5491
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absolute parameters of 509 main-sequence stars selected from the components of detached eclipsing spectroscopic binaries in the solar neighbourhood are used to study mass-luminosity, mass-radius, and mass-effective temperature relations (MLR, MRR, and MTR). The MLR function is found better if expressed by a six-piece classical MLR (L{prop.to}M^{alpha}^) rather than a fifth or a sixth degree polynomial within the mass range of 0.179<=M/M_{sun}_<=31. The break points separating the mass ranges with classical MLR do not appear to us to be arbitrary. Instead, the data indicate abrupt changes along the mass axis in the mean energy generation per unit of stellar mass. Unlike the MLR function, the MRR and MTR functions cannot be determined over the full range of masses. A single-piece MRR function is calibrated from the radii of stars with M<=1.5M_{sun}_, while a second single-piece MTR function is found for stars with M>1.5M_{sun}_. The missing part of the MRR is computed from the MLR and MTR, while the missing part of the MTR is computed from the MLR and MRR. As a result, we have interrelated the MLR, MRR, and MTR, which are useful in determining the typical absolute physical parameters of main-sequence stars of given masses. These functions are also useful to estimate typical absolute physical parameters from typical T_eff_ values. Thus, we were able to estimate the typical absolute physical parameters of main-sequence stars observed in the Sejong Open cluster Survey, based on that survey's published values for Teff. Since typical absolute physical parameters of main-sequence stars cannot normally be determined in such photometric surveys, the interrelated functions are shown to be useful to compute such missing parameters from similar surveys.
- ID:
- ivo://CDS.VizieR/J/other/A+AT/25.185
- Title:
- Absolute proper motions of globular clusters
- Short Name:
- J/other/A+AT/25.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The absolute proper motions for a total of 92 globular clusters of the Milky Way (60% of all clusters included in the catalogue published by Harris, 1996, Cat. VII/195) are inferred from the UCAC2 proper motions of their likely member stars. The median formal error of the cluster proper motions is equal to 0.8marcsec/yr in both right ascension and declination, whereas the proper-motion errors of individual clusters range from 0.2 to 3marcsec/yr. Tests performed demonstrate the overall validity of the cluster motions; the resulting transverse velocities remain, on the average, virtually constant out to a heliocentric distance of 15kpc and the full space velocity of most of the clusters relative to the Galactic centre remains, on the average, unchanged near 190km/s out to a Galactocentric distance of about 20kpc, in agreement with the overall isothermal structure of the Galactic halo.
- ID:
- ivo://CDS.VizieR/J/ApJ/691/1400
- Title:
- Absolute properties of CM Dra
- Short Name:
- J/ApJ/691/1400
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present a complete reanalysis of the eclipsing systems, CM Dra, composed of two dM4.5 stars. New and existing light curves as well as a radial velocity curve are modeled to measure the physical properties of both components. The masses and radii determined for the components of CM Dra are M1=0.2310+/-0.0009M_{sun}_, M2=0.2141+/-0.0010M_{sun}_, R1=0.2534+/-0.0019R_{sun}_, and R2=0.2396+/-0.0015R_{sun}_. With relative uncertainties well below the 1% level, these values constitute the most accurate properties to date for fully convective stars.
- ID:
- ivo://CDS.VizieR/J/AJ/138/1622
- Title:
- Absolute properties of LV Her
- Short Name:
- J/AJ/138/1622
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report extensive spectroscopic and differential V-band photometric observations of the 18.4 day detached double-lined eclipsing binary LV Her (F9V), which has the highest eccentricity (e~0.613) among the systems with well-measured properties. We determine the absolute masses and radii of the components to be M1=1.193+/-0.010M_{sun}_, M2=1.1698+/-0.0081M_{sun}_, R1=1.358+/-0.012R_{sun}_, and R2=1.313+/-0.011R_{sun}_, with fractional errors of 0.9% or better. The effective temperatures are 6060+/-150K and 6030+/-150K, respectively, and the overall metallicity is estimated to be [m/H]=+0.08+/-0.21. A comparison with current stellar evolution models for this composition indicates an excellent fit for an age between 3.8 and 4.2Gyr, with both stars being near the middle of their main-sequence lifetimes. Full integration of the equations for tidal evolution is consistent with the high eccentricity, and suggests that the stars' spin axes are aligned with the orbital axis, and that their rotations should be pseudo-synchronized. The latter prediction is not quite in agreement with the measured projected rotational velocities.
- ID:
- ivo://CDS.VizieR/J/AJ/145/167
- Title:
- Abundances of LX Per
- Short Name:
- J/AJ/145/167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic observations of LX Per carried out using the Korean Bohyunsan Observatory Echelle Spectrograph (BOES) with spectral resolving power R=80000. The spectrograph was attached to the 1.8m telescope. The fit of synthetic spectra to the observed spectrum of the system allowed us to find the component parameters and the abundances of chemical elements in the atmospheres of the components. The strong CaII H&K emissions are confirmed; we also found emission lines in the CaII reversals' triplet absorptions at the wavelengths of 8498, 8542, and 8662{AA} in the spectrum of the cooler component of LX Per. A unique photometric solution using the distorted light curves of three different epochs was made. The spot model light curves were fitted to the 1981, 1982, and 1983 observations successfully by adjusting only spot parameters. We could infer that the variation of spot location and size was the main reason for the changing shape of light curves. The main feature of the abundance patterns of both components was the apparent deficiency of heavy (Z>30) elements. Only elements with strong lines, namely Y and Ba, were detected. Correlations of relative abundances of chemical elements with condensation temperatures and second ionization potentials of these elements, which can be explained by the accretion of dust and gas, were found.
- ID:
- ivo://CDS.VizieR/J/AJ/144/35
- Title:
- Abundances of the eclipsing binary ZZ Boo
- Short Name:
- J/AJ/144/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigated ZZ Boo using a high-resolution (R=80000) spectrum obtained at the BOES echelle spectrograph attached to a 1.8m telescope at the Bohuynsan observatory in Korea. The atmospheric parameters of the components were found using the published photometrical observations and the abundance analysis of iron lines: the flux ratio of the components F_A_/F_B_=1.12+/-0.15, the effective temperatures of the components T_eff_=6860+/-20K and 6930+/-20K, the surface gravities log g=3.72+/-0.10 and 3.84+/-0.10, the metallicities [Fe/H]=-0.10+/-0.08 and -0.03+/-0.10, and the projected rotation velocities vsin i=11.9+/-0.4km/s and 19.3+/-0.8km/s for the primary and secondary components, respectively. The pointed errors are the formal errors of the methods used; the systematic errors of the temperatures, gravities, metallicities, and projected rotational velocities can be as high as 250-300K, 0.3dex, 0.15dex, and 4km/s, respectively. The abundances of 24 and 22 chemical elements were determined in the atmospheres of the components. The abundance pattern of the primary component shows the solar or slightly undersolar abundances of all elements. CNO abundances are close to solar values. The abundance pattern of this component resembles those of {lambda} Boo type stars. The abundances of light elements, except oxygen, in the atmosphere of the secondary component are practically solar. The abundances of barium and two detected lanthanides are close to the solar values; the overabundance of oxygen is 0.9dex. The abundances of two components are evidently different. The comparison of relative abundances with the condensation temperatures and second ionization potentials of the elements confirms the difference in abundance patterns and allows discussion of the different accretion scenarios for two components of this binary system.
- ID:
- ivo://CDS.VizieR/J/MNRAS/415/2238
- Title:
- Abundances of TX UMa
- Short Name:
- J/MNRAS/415/2238
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution echelle spectra have been obtained of the semi-detached Algol-type eclipsing binary system, TX UMa with the high-resolution echelle spectrographs of the 1.8m telescope at Bohyunsan Optical Astronomy Observatory in Korea and of the 2.0m telescope of Peak Terskol Observatory in Russia. New accurate radial velocities of its components have been measured.
- ID:
- ivo://CDS.VizieR/J/AJ/131/621
- Title:
- A catalog of 1022 bright contact binary stars
- Short Name:
- J/AJ/131/621
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we describe a large new sample of contact binary stars extracted in a uniform manner from sky patrol data taken by the ROTSE-I telescope. Extensive ROTSE-I light-curve data are combined with J-, H-, and K-band near-infrared data taken from the Two Micron All Sky Survey to add color information.
- ID:
- ivo://CDS.VizieR/J/other/A+ARV/18.67
- Title:
- Accurate masses and radii of normal stars
- Short Name:
- J/other/A+ARV/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This article presents and discusses a critical compilation of accurate, fundamental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94 eclipsing systems, and alpha Centauri) that satisfy our criterion that the mass and radius of both stars be known within errors of +/-3% accuracy or better. All of them are non-interacting systems, and so the stars should have evolved as if they were single. This sample more than doubles that of the earlier similar review by Andersen (Astron. Astrophys. Rev. 3:91-126, 1991), extends the mass range at both ends and, for the first time, includes an extragalactic binary. In every case, we have examined the original data and recomputed the stellar parameters with a consistent set of assumptions and physical constants.
