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- ID:
- ivo://CDS.VizieR/J/A+A/557/A13
- Title:
- 3 eclipsing high-mass binaries light curve
- Short Name:
- J/A+A/557/A13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of a comprehensive photometric O-star survey performed with a robotic twin refractor at the Universitatssternwarte Bochum located near Cerro Armazones in Chile. For three high-mass stars, Pismis 24-1, CPD-51 8946, and HD 319702, we determined the period through the Lafler-Kinman algorithm and modelled the light curves within the framework of the Roche geometry.
- ID:
- ivo://CDS.VizieR/V/64
- Title:
- Eighth Orbital Elements of Spectroscopic Binaries
- Short Name:
- V/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The complete description of the catalogue, as well as the notes, is to be found in the Publ. Dominion Astrophys. Obs. 17 (1989). The present machine-readable version was transformed from the file provided by A.H. Batten for easier computer readability. Compared to the printed version, please note the following: 1) The four columns No. f(m) m.sin^3(i) a.sin(i) are NOT included in the computer version. No. (running number) is the line number of the main file (from 1 to 1469) f(m) (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(1)**3 * P a(*)sin i (expressed in km) can be computed from the Fortran formula 13751 * sqrt(1-e*e) * K(*) * P m(*)sin3i (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(*) * (K(1)+K(2))**2 * P The parameters are K(*) = velocity amplitude of the components, expressed in km/s; P = Period, expressed in days, sometimes in years; e = eccentricity 2) The notes, which make the bulk of the printed catalogue (pages 129-304), are NOT included.
- ID:
- ivo://CDS.VizieR/J/A+AS/136/453
- Title:
- Equivalent widths of spectroscopic binaries
- Short Name:
- J/A+AS/136/453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution spectroscopic observations are presented for 19 single-lined binaries (giants and dwarfs) with orbital elements and mass functions similar to those of barium stars, two radial velocity non-variable barium stars, and two standards. All binary systems contain an unseen low-mass component, presumably, a white dwarf. The equivalent widths and oscillator strengths are given for all measured spectral lines.
- ID:
- ivo://CDS.VizieR/J/A+A/630/A80
- Title:
- EREBOS project. I.
- Short Name:
- J/A+A/630/A80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Eclipsing post-common-envelope binaries are highly important for resolving the poorly understood, very short-lived common-envelope phase of stellar evolution. Most hot subdwarfs (sdO/Bs) are the bare helium-burning cores of red giants that have lost almost all of their hydrogen envelope. This mass loss is often triggered by common-envelope interactions with close stellar or even substellar companions. Cool companions to hot subdwarf stars such as late-type stars and brown dwarfs are detectable from characteristic light-curve variations - reflection effects and often eclipses. In the recently published catalog of eclipsing binaries in the Galactic Bulge and in the Asteroid Terrestrial-impact Last Alert System (ATLAS) survey, we discovered 125 new eclipsing systems showing a reflection effect seen by visual inspection of the light curves and using a machine-learning algorithm, in addition to the 36 systems previously discovered by the Optical Gravitational Lesing Experiment (OGLE) team. The Eclipsing Reflection Effect Binaries from Optical Surveys (EREBOS) project aims at analyzing all newly discovered eclipsing binaries of the HW Vir type (hot subdwarf + close, cool companion) based on a spectroscopic and photometric follow up to derive the mass distribution of the companions, constrain the fraction of substellar companions, and determine the minimum mass needed to strip off the red-giant envelope. To constrain the nature of the primary we derived the absolute magnitude and the reduced proper motion of all our targets with the help of the parallaxes and proper motions measured by the Gaia mission and compared those to the Gaia white-dwarf candidate catalog. It was possible to derive the nature of a subset of our targets, for which observed spectra are available, by measuring the atmospheric parameter of the primary, confirming that less than 10% of our systems are not sdO/Bs with cool companions but are white dwarfs or central stars of planetary nebula. This large sample of eclipsing hot subdwarfs with cool companions allowed us to derive a significant period distribution for hot subdwarfs with cool companions for the first time showing that the period distribution is much broader than previously thought and is ideally suited to finding the lowest-mass companions to hot subdwarf stars. The comparison with related binary populations shows that the period distribution of HW Vir systems is very similar to WD+dM systems and central stars of planetary nebula with cool companions. In the future, several new photometric surveys will be carried out, which will further increase the sample of this project, providing the potential to test many aspects of common-envelope theory and binary evolution.
- ID:
- ivo://CDS.VizieR/J/MNRAS/475/1960
- Title:
- ESPaDOnS spectropolarimeter obs. of M dwarfs
- Short Name:
- J/MNRAS/475/1960
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Present and future high-precision radial-velocity spectrometers dedicated to the discovery of low-mass planets orbiting low-mass dwarfs need to focus on the best selected stars to make an efficient use of telescope time. In the framework of the preparation of the SPIRou Input Catalogue (SPIC), the CoolSnap program aims at screening M dwarfs in the solar neighbourhood against binarity, rapid rotation, activity, etc. To optimize the selection, this paper describes the methods used to compute effective temperature, metallicity, projected rotation velocity of a large sample of 440 M dwarfs observed in the visible with the high-resolution spectropolarimeter Echelle SpectroPolArimetric Device for the ObservatioN of Stars (ESPaDOnS) at Canada-France-Hawaii Telescope. It also summarizes known and newly discovered spectroscopic binaries, and stars known to belong to visual multiple systems. A calibration of the projected rotation velocity versus measured line widths for M dwarfs observed by the ESPaDOnS spectropolarimeter is derived, and the resulting values are compared to equatorial rotation velocities deduced from rotation periods and radii. A comparison of the derived effective temperatures and metallicities with literature values is also conducted. Finally, the radial-velocity uncertainty of each star in the sample is estimated, to narrow down the selection of stars to be included into the SPIC.
- ID:
- ivo://CDS.VizieR/J/A+A/585/A46
- Title:
- Extrasolar planets. Radial velocities of 5 stars
- Short Name:
- J/A+A/585/A46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Long-period brown dwarf companions detected in radial velocity surveys are important targets for direct imaging and astrometry to calibrate the mass-luminosity relation of substellar objects. Through a 20-year radial velocity monitoring of solar-type stars that began with ELODIE and was extended with SOPHIE spectrographs, giant exoplanets and brown dwarfs with orbital periods longer than ten years are discovered. We report the detection of five new potential brown dwarfs with minimum masses between 32 and 83M_Jup_ orbiting solar-type stars with periods longer than ten years. An upper mass limit of these companions is provided using astrometric Hipparcos data, high-angular resolution imaging made with PUEO, and a deep analysis of the cross-correlation function of the main stellar spectra to search for blend effects or faint secondary components. These objects double the number of known brown dwarf companions with orbital periods longer than ten years and reinforce the conclusion that the occurrence of such objects increases with orbital separation. With a projected separation larger than 100mas, all these brown dwarf candidates are appropriate targets for high-contrast and high angular resolution imaging.
- ID:
- ivo://CDS.VizieR/J/A+A/347/583
- Title:
- EZ CMa spectroscopy
- Short Name:
- J/A+A/347/583
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The table contains the window averaged flux (WAF) in two windows located at the P Cyg absorption component of the NV 4604/4620 doublet and the kurtosis of the HeII 4540 and HeII 4686 lines of the star EZ CMa. The three data sets are stored in three different files with the same format.
- ID:
- ivo://CDS.VizieR/J/PASJ/60/209
- Title:
- Faint companions around YSOs in TMC
- Short Name:
- J/PASJ/60/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted near-infrared spectroscopy of 26 faint objects around young stellar objects in the Taurus molecular cloud. These objects were detected during a course of near-infrared coronagraphic searches for companions around 72 young stellar objects with the Subaru Telescope and the near-infrared coronagraph CIAO (coronagraphic imager with adaptive optics). A comparison of the Subaru and HST archive images revealed that three central stars and faint companions share common proper motions, suggesting that they are physically associated with each other. None of the 26 sources show deep water absorption bands at near-infrared, except for DH Tau B. This result indicates that all of them, but DH Tau B, have a high photospheric temperature or a large amount of excess from circumstellar materials.
- ID:
- ivo://CDS.VizieR/J/ApJ/851/31
- Title:
- 2FGL J0846.0+2820 opt. counterpart follow-up
- Short Name:
- J/ApJ/851/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical photometric and spectroscopic observations of the likely stellar counterpart to the unassociated Fermi Large Area Telescope (LAT) {gamma}-ray source 2FGL J0846.0+2820, selected for study based on positional coincidences of optical variables with unassociated LAT sources. Using optical spectroscopy from the SOAR telescope, we have identified a late-G giant in an eccentric (e=0.06) 8.133-day orbit with an invisible primary. Modeling the spectroscopy and photometry together led us to infer a heavy neutron star primary of ~2M_{sun}_ and a partially stripped giant secondary of ~0.8M_{sun}_. H{alpha} emission is observed in some of the spectra, perhaps consistent with the presence of a faint accretion disk. We find that the {gamma}-ray flux of 2FGL J0846.0+2820 dropped substantially in mid-2009, accompanied by an increased variation in the optical brightness, and since then, it has not been detected by Fermi. The long period and giant secondary are reminiscent of the {gamma}-ray bright binary 1FGL J1417.7-4407, which hosts a millisecond pulsar (MSP) apparently in the final stages of the pulsar recycling process. The discovery of 2FGL J0846.0+2820 suggests the identification of a new subclass of MSP binaries that are the likely progenitors of typical field MSPs.
