- 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.
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Search Results
- 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/152/49
- Title:
- Algol-type binaries. IX. V548 Cyg
- Short Name:
- J/AJ/152/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new UV light curve of the Algol eclipsing binary V548 Cyg obtained with the Lunar Ultraviolet Telescope. We model the UV light curve together with two previously published (B and V) light curves, primary star radial velocities, and eclipse timings in a unified multi-data-type solution and determine orbital parameters and absolute dimensions. Timing residuals hint at the presence of a third star in the system. This star is possibly the source of the third light that is needed to obtain a good fit to each of the light curves simultaneously. The light-time oscillation in the timing residuals has a period of either ~19 or ~46years. The third body orbit inclination would have to be low (23{deg} or 15{deg}, respectively) for the third star to have a mass of ~1.5M_{Sun}_, which would be expected for a main-sequence star of color B-V~0.32, as determined from the light curve solution. In an H-R diagram, the mass-gaining, primary component of V548 Cyg is located between the zero-age and terminal-age main sequence for solar composition stars, and close to the 0.4Gyr isochrone.
- 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/ApJS/211/27
- Title:
- An atlas of FUV spectra of 31 Cyg
- Short Name:
- J/ApJS/211/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The {zeta} Aurigae system 31 Cygni (K4 Ib + B4 V) was observed by the FUSE satellite during total eclipse and at three phases during chromospheric eclipse. We present the coadded, calibrated spectra and atlases with line identifications. During total eclipse, emission from high ionization states (e.g., Fe III and Cr III) shows asymmetric profiles redshifted from the systemic velocity, while emission from lower ionization states (e.g., Fe II and O I) appears more symmetric and is centered closer to the systemic velocity. Absorption from neutral and singly ionized elements is detected during chromospheric eclipse. Late in chromospheric eclipse, absorption from the K star wind is detected at a terminal velocity of ~80km/s. These atlases will be useful for interpreting the far-UV spectra of other {zeta} Aur systems, as the observed FUSE spectra of 32 Cyg, KQ Pup, and VV Cep during chromospheric eclipse resemble that of 31 Cyg.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/139/1360
- Title:
- AO Ser VR light curves
- Short Name:
- J/AJ/139/1360
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first multiband photometry for the semidetached eclipsing binary AO Serpentis, observed on seven nights between 2009 April and July at the Weihai Observatory of Shandong University. By using the 2003 version of the Wilson-Devinney code, the photometric solutions of AO Ser and a similar object V338 Her were (re)deduced. The spectral types and orbital periods are A2 and P=0.8793-days for AO Ser, F1V and P=1.3057-days for V338 Her.
- ID:
- ivo://CDS.VizieR/J/A+AS/109/425
- Title:
- AO Vel four-colour photometry
- Short Name:
- J/A+AS/109/425
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
