- 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.
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- 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/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.
- ID:
- ivo://CDS.VizieR/J/AJ/156/241
- Title:
- A first catalog of variable stars measured by ATLAS
- Short Name:
- J/AJ/156/241
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Asteroid Terrestrial-impact Last Alert System (ATLAS) carries out its primary planetary defense mission by surveying about 13000 deg^2^ at least four times per night. The resulting data set is useful for the discovery of variable stars to a magnitude limit fainter than r~18, with amplitudes down to 0.02 mag for bright objects. Here, we present a Data Release One catalog of variable stars based on analyzing the light curves of 142 million stars that were measured at least 100 times in the first two years of ATLAS operations. Using a Lomb-Scargle periodogram and other variability metrics, we identify 4.7 million candidate variables. Through the Space Telescope Science Institute, we publicly release light curves for all of them, together with a vector of 169 classification features for each star. We do this at the level of unconfirmed candidate variables in order to provide the community with a large set of homogeneously analyzed photometry and to avoid pre-judging which types of objects others may find most interesting. We use machine learning to classify the candidates into 15 different broad categories based on light-curve morphology. About 10% (427000 stars) pass extensive tests designed to screen out spurious variability detections: we label these as "probable" variables. Of these, 214000 receive specific classifications as eclipsing binaries, pulsating, Mira-type, or sinusoidal variables: these are the "classified" variables. New discoveries among the probable variables number 315000, while 141000 of the classified variables are new, including about 10400 pulsating variables, 2060 Mira stars, and 74700 eclipsing binaries.
- ID:
- ivo://CDS.VizieR/J/AZh/78/1104
- Title:
- Age and metallicity in eclipsing binaries
- Short Name:
- J/AZh/78/1104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on the set of high accuracy observational data on the components of SB2 eclipsing binaries and the grid of stellar models calculated by Geneva group for the wide range of masses and abundances, we estimate most probable ages and metallicities for the 43 systems using constraints arising from common origin of the components.
- ID:
- ivo://CDS.VizieR/J/AJ/147/145
- Title:
- Algol-type binaries. VIII. DI Peg & AF Gem
- Short Name:
- J/AJ/147/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New extensive photometry for two triple binary stars, DI Peg and AF Gem, was performed from 2012 October to 2013 January, with two small telescopes at Xinglong station (XLs) of NAOC. From new multi-color observations and previously published ones in literature, the photometric models were (re)deduced using the updated Wilson-Devinney code. The results indicated that the low third lights exist in two classic Algol-type binaries, whose fill-out factors for the more massive components are f_p_=78.2(+/-0.4)% for DI Peg, and f_p_=69.0(+/-0.3)% for AF Gem, respectively. Through analyzing the O-C curves, the orbital periods for two binaries change in the complicated mode. The period of DI Peg possibly appears to show two light-time orbits, whose modulated periods are P_3_=54.6(+/-0.5)yr and P_4_=23.0(+/-0.6)yr, respectively. The inferred minimum masses for the inner and outer sub-stellar companions are M_in_=0.095M_{sun}_ and M_out_=0.170M_{sun}_, respectively. Therefore, DI Peg may be a quadruple star. The orbital period of AF Gem appears to show a continuous period decrease or a cyclic variation; the latter may be preferable. The cyclic oscillation, with a period of 120.3(+/-2.5)yr, may be attributed to the light-time effect due to the third body. This kind of additional companion may extract angular momentum from the central system, which may play a key role in the evolution of the binary.
- ID:
- ivo://CDS.VizieR/J/A+A/405/231
- Title:
- Algol-type eclipsing binaries differential photometry
- Short Name:
- J/A+A/405/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a systematic search for pulsating components in Algol-type eclipsing binary systems. A total number of 14 eclipsing binaries with A-F spectral type primary components were observed for 22 nights. We confirmed small-amplitude oscillating features of a recently detected pulsator TW Dra, which has a pulsating period of 0.053-day and a semi-amplitude of about 5-mmag in B-passband. We discovered new pulsating components in two eclipsing binaries of RX Hya and AB Per. The primary component of RX Hya is pulsating with a dominant period of 0.052-day and a semi-amplitude of about 7-mmag. AB Per has also a pulsating component with a period of 0.196-day and a semi-amplitude of about 10-mmag in B-passband. We suggest that these two new pulsators are members of the newly introduced group of mass-accreting pulsating stars in semi-detached Algol-type eclipsing binary systems.
- ID:
- ivo://CDS.VizieR/J/MNRAS/373/435
- Title:
- Angular momentum evolution of Algol binaries
- Short Name:
- J/MNRAS/373/435
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled the well-determined absolute parameters of Algol-type binaries. The lists contain the parameters of 74 detached and 61 semi-detached close binaries. The double-lined eclipsing binaries provide not only the most accurate determinations of stellar mass, radius and temperatures but also distance-independent luminosity for each of their individual components. The distributions of the primary and secondary masses of detached binaries (DBs) are similar, whilst the secondary masses of the semidetached binaries (SDBs) are mostly smaller than 2M_{sun}_ with a peak in the M2-bin (0.21-1.0). The components of the DBs are almost all located in the main-sequence band. On the contrary, the secondary components of the SDBs have larger radii and luminosity with respect to the same mass and the same effective temperature of main-sequence counterparts. They occupy a region of the Hertzsprung-Russell diagram between terminal-age main sequence and giants.
- ID:
- ivo://CDS.VizieR/J/A+A/626/A69
- Title:
- An old nova remnant in M22
- Short Name:
- J/A+A/626/A69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A nova is a cataclysmic event on the surface of a white dwarf in a binary system that increases the overall brightness by several orders of magnitude. Although binary systems with a white dwarf are expected to be overabundant in globular clusters (GCs) compared to the Galaxy, only two novae from Galactic globular clusters have been observed. We present the discovery of an emission nebula in the Galactic globular cluster M 22 (NGC 6656) in observations made with the integral-field spectrograph MUSE. We extract the spectrum of the nebula and use the radial velocity determined from the emission lines to confirm that the nebula is part of NGC 6656. Emission-line ratios are used to determine the electron temperature and density. It is estimated to have a mass of 1 to 17x10^-5^ solar masses. This mass and the emission-line ratios indicate that the nebula is a nova remnant. Its position coincides with the reported location of a 'guest star', an ancient Chinese term for transients, observed in May 48 BCE. With this discovery, this nova may be one of the oldest confirmed extrasolar events recorded in human history.
