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- ID:
- ivo://CDS.VizieR/J/other/AstBu/62.235
- Title:
- Metal-poor stars speckle interferometry
- Short Name:
- J/other/AstBu/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of speckle-interferometric observations of 109 high proper-motion metal-poor stars made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We resolve eight objects G102-20, G191-55, BD+19 1185A, G89-14, G87-45, G87-47, G111-38, and G114-25 into individual components and we are the first to astrometrically resolve seven of these stars. New resolved systems included two triple (G111-38, G87-47) and one quadruple (G89-14) star. The ratio of single:binary:triple:quadruple systems among the stars of our sample is equal to 71:28:6:1.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/63.278
- Title:
- Metal-poor stars speckle interferometry
- Short Name:
- J/other/AstBu/63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of speckle interferometric observations of 115 metal-poor stars ([m/H]<-1) within 250pc from the Sun and with proper motions mu>~0.2"/yr, made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, are reported. Close companions with separations ranging from 0.034" to 1" were observed for 12 objects - G76-21, G59-1, G63-46, G135-16, G168-42, G141-47, G142-44, G190-10, G28-43, G217-8, G130-7, and G89-14 - eight of them are astrometrically resolved for the first time. The newly resolved systems include one triple star - G190-10. If combined with spectroscopic and visual data, our results imply a single:binary:triple:quadruple star ratio of 147:64:9:1 for a sample of 221 primary components of halo and thick-disk stars.
- ID:
- ivo://CDS.VizieR/J/AJ/158/239
- Title:
- Metal-rich host stars abundances & equivalent widths
- Short Name:
- J/AJ/158/239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The relationship between the compositions of giant planets and their host stars is of fundamental interest in understanding planet formation. The solar system giant planets are enhanced above solar composition in metals, both in their visible atmospheres and bulk compositions. A key question is whether the metal enrichment of giant exoplanets is correlated with that of their host stars. Thorngren et al. (2016, J/ApJ/831/64) showed that in cool (T_eq_<1000 K) giant exoplanets, the total heavy-element mass increases with total M_p_ and the heavy-element enrichment relative to the parent star decreases with total M_p_. In their work, the host star metallicity was derived from literature [Fe/H] measurements. Here we conduct a more detailed and uniform study to determine whether different host star metals (C, O, Mg, Si, Fe, and Ni) correlate with the bulk metallicity of their planets, using correlation tests and Bayesian linear fits. We present new host star abundances of 19 cool giant planet systems, and combine these with existing host star data for a total of 22 cool giant planet systems (24 planets). Surprisingly, we find no clear correlation between stellar metallicity and planetary residual metallicity (the relative amount of metal versus that expected from the planet mass alone), which is in conflict with common predictions from formation models. We also find a potential correlation between residual planet metals and stellar volatile-to-refractory element ratios. These results provide intriguing new relationships between giant planet and host star compositions for future modeling studies of planet formation.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A108
- Title:
- 150MHz emission from exoplanets
- Short Name:
- J/A+A/562/A108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ongoing radio continuum TIFR GMRT Sky Survey (TGSS) using the Giant Metrewave Radio Telescope (GMRT) at 150MHz offers an unprecedented opportunity to undertake a fairly deep search for low-frequency radio emission from nearby extrasolar planets. Currently TGSS images are available for a little over a steradian, encompassing 175 confirmed exoplanetary systems. We have searched for their radio counterparts in the TGSS (150MHz), supplemented with a search in the NRAO VLA Sky Survey (NVSS) and the VLA FIRST survey at 1.4GHz. For 171 planetary systems, we find no evidence of radio emission in the TGSS maps, placing a 3{sigma} upper limit between 8.7mJy and 136mJy (median ~24.8mJy) at 150MHz.
- ID:
- ivo://CDS.VizieR/J/AJ/116/917
- Title:
- Micrometer measures of double stars
- Short Name:
- J/AJ/116/917
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Micrometer measures of 795 double stars made with the 26 inch (0.66m) refractor of the US Naval Observatory from 1984 to 1990 are presented.
- ID:
- ivo://CDS.VizieR/J/ApJ/636/932
- Title:
- Mid-infrared survey of T Tauri stars
- Short Name:
- J/ApJ/636/932
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a high spatial resolution, 10-20{mu}m survey of 65 T Tauri binary stars in Taurus, Ophiuchus, and Corona Australis using the Keck 10m telescopes. Designed to probe the inner ~1AU region of the circumstellar disks around the individual stellar components in these binary systems, this study increases the number of binaries with spatially resolved measurements at 10{mu}m by a factor of ~5.
- ID:
- ivo://CDS.VizieR/J/ApJ/751/115
- Title:
- Millimeter emission from Taurus binary systems
- Short Name:
- J/ApJ/751/115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a high angular resolution millimeter-wave dust continuum imaging survey of circumstellar material associated with the individual components of 23 multiple star systems in the Taurus-Auriga young cluster. Combined with previous measurements in the literature, these new data permit a comprehensive look at how the millimeter luminosity (a rough tracer of disk mass) relates to the separation and mass of a stellar companion. Approximately one-third (28%-37%) of the individual stars in multiple systems have detectable millimeter emission, an incidence rate half that for single stars (~62%) which does not depend on the number of companions. There is a strong, positive correlation between the luminosity and projected separation (a_p_) of a stellar pair. Wide pairs (a_p_>300AU) have a similar luminosity distribution as single stars, medium pairs (a_p_{approx}30-300AU) are a factor of five fainter, and close pairs (a_p_<30AU) are ~5x fainter yet (aside from a small, but notable population of bright circumbinary disks). In most cases, the emission is dominated by a disk around the primary (or a wide tertiary in hierarchical triples), but there is no clear relationship between luminosity and stellar mass ratio.
- ID:
- ivo://CDS.VizieR/J/A+AS/135/231
- Title:
- Mining in the Hipparcos raw data
- Short Name:
- J/A+AS/135/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We give 139 reprocessed problem double stars using Hipparcos data
- ID:
- ivo://CDS.VizieR/III/106
- Title:
- MK Classification of Visual Multiples
- Short Name:
- III/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The spectral types listed here represent about one-third of a program of MK classification of all the Northern (Dec>-30deg) visual components brighter than B~8.0mag. The spectra used were obtained in 1969-1980 with the Cassegrain spectrograph attached to the Kitt Peak No.2 91-cm telescope. The grating spectra have a dispersion of 128{AA}/mm, and are 1.2mm wide; they are overexposed and underdeveloped to minimize grain. The spectra were classified against standards of the "Revised MK Spectral Atlas for stars earlier than the Sun" by Morgan, Abt and Tapscott (Yerkes Obs. 1978) and of the "Spectral classification" of Morgan and Keenan (1973ARA&A..11...29M). Accurate positions, V magnitudes rounded to 0.1 mag, and remarks were added by B. Skiff in June 2004 as the file "more.dat"; some typos in the catalog were also corrected (see the "History" section below).