- ID:
- ivo://CDS.VizieR/J/AJ/156/48
- Title:
- Orbits of subsystems in six multiple stars. III.
- Short Name:
- J/AJ/156/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic orbits are computed for inner pairs in six nearby hierarchical multiple systems (HIP 35733, 95106/95110, 105441, 105585/105569, 105947, and 109951). Radial velocities and resolved measurements, when available, are used to derive combined sets of outer orbital elements for three systems. Each multiple system is discussed individually. Additionally, HIP 115087 is a simple 7.9-day single-lined binary. Although the minimum companion mass is substellar (in the brown dwarf desert regime), it appears to be a 0.2 solar-mass star in a low-inclination orbit.
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- ID:
- ivo://CDS.VizieR/J/AZh/88/143
- Title:
- ORICAT Catalog of Stars in Orion Great Nebula
- Short Name:
- J/AZh/88/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Six Tautenburg 2-m Schmidt telescope plates have been used to derive proper motions for 12740 stars down to Blim=18.5 in the region centered at RA=83.45grad, Dec=-5.20grad of the Great Nebula in Orion. Each plate covers a 3x3 grad region of sky, with a scale of 51.4"/mm. The largest difference between the epochs is 36 years. The photographic plates were scanned using Tautenburg Observatory plate scanner. The accuracy of the scans was 0.5micron, and the scale was 1000pixels/mm. The rectangular coordinates x, y and instrumental magnitudes were then determined using a dedicated software. To convert the scanned positions to the equatorial coordinates we adopt reference stars from the ACT catalog. Mean errors of position determinations are 3-4mas. The components of the proper motions and their rms uncertainties were obtained via linear least-squares fit to individual rectangular coordinates as a function of the observing epoch with no less than three epochs for every proper motion. The mean measurement uncertainty is 3.5mas/yr in magnitude interval 15-19 and 5.0mas/yr outside this interval. The photometry has been taken from Walker (1969) for B-magnitudes, and from USNO-A2.0 for R-magnitudes. Mean errors for photometry are 0.03mag in B and 0.25mag in R. The ORICAT is supplemented with the data of Parenago (1954) (stars with numbers greater 17000), and includes 13 577 stars in total. ACKNOWLEDGMENTS. We thank E. Schilbach, N.V. Kharchenko, and R.D. Scholz for numerous discussions of the results, and J. Brunzendorf and H. Meusinger for help in organizing the work at Jena Observatory.
- ID:
- ivo://CDS.VizieR/J/AJ/159/272
- Title:
- Orion Nebula Cluster PMs with HST Treasury Program
- Short Name:
- J/AJ/159/272
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of high-precision proper motions in the Orion Nebula Cluster (ONC), based on Treasury Program observations with the Hubble Space Telescope's (HST) ACS/WFC camera. Our catalog contains 2454 objects in the magnitude range of 14.2<m_F775W_<24.7, thus probing the stellar masses of the ONC from ~0.4M{sun} down to ~0.02M{sun} over an area of ~550arcmin^2^. We provide a number of internal velocity dispersion estimates for the ONC that indicate a weak dependence on stellar location and mass. There is good agreement with the published velocity dispersion estimates, although nearly all of them (including ours at {sigma }_{v,x}_=0.94 and {sigma}_{v,y}_=1.25mas/yr) might be biased by the overlapping young stellar populations of Orion A. We identified four new ONC candidate runaways based on HST and the Gaia DR 2 data, all with masses less than ~1M{sun}. The total census of known candidate runaway sources is 10-one of the largest samples ever found in any Milky Way open star cluster. Surprisingly, none of them have tangential velocities exceeding 20km/s. If most of them indeed originated in the ONC, it may compel the re-examination of dynamical processes in very young star clusters. It appears that the mass function of the ONC is not significantly affected by the lost runaways.
- ID:
- ivo://CDS.VizieR/J/AZh/83/821
- Title:
- Orion Spiral Arm CAtalogue (OSACA)
- Short Name:
- J/AZh/83/821
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We transformed radial velocities compiled from more than 1400 published sources, including the Geneva-Copenhagen survey of the solar neighborhood (2004, Nordstrom et al., Cat. <V/117>), into a uniform system based on the radial velocities of 854 standard stars in our list (Gontcharov, 2006, Cat. <III/252> ). This enabled us to calculate the average weighted radial velocities for more than 25000 HIPPARCOS stars located in the local Galactic spiral arm (Orion arm) with a median error of 1km/s. We use these radial velocities together with the stars coordinates, parallaxes, and proper motions to determine their Galactic coordinates and space velocities. These quantities, along with other parameters of the stars, are available from the continuously updated Orion Spiral Arm CAtalogue (OSACA) and the associated database. We perform a kinematic analysis of the stars by applying an Ogorodnikov-Milne model to the OSACA data. The kinematics of the nearest single and multiple main-sequence stars differ substantially.
- ID:
- ivo://CDS.VizieR/J/MNRAS/485/2312
- Title:
- Outer Galactic disk A and F stars space motions
- Short Name:
- J/MNRAS/485/2312
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A and F stars can be used as probes of outer Galactic disk kinematics: here we extend the work of Harris et al. (2018, Cat. J/MNRAS/475/1680) by crossmatching their A/F sample with Gaia DR2 to bring in proper motions. These are combined with the already measured radial velocities and spectro-photometric distances to obtain full space motions. We use this sample of 1173 stars, located in two pencil-beam sightlines (l=178{deg} and l=118{deg}), to sample the Galactocentric velocity field out to almost R_G_=15kpc. We find there are significant differences in all three (radial, azimuthal and vertical) kinematic components between the two directions. The rotation curve is roughly flat in the anticentre direction, confirming and extending the result of Kawata et al. (2018MNRAS.479L.108K) thanks to the greater reach of our spectro-photometric distance scale. However at l=118{deg} the circular velocity rises outwards from R_G_=10.5kpc and there is a more pronounced gradient in radial motion than is seen at l=178{deg}. Furthermore, the A star radial motion differs from the F stars by ~10km/s. We discuss our findings in the context of perturbers potentially responsible for the trends, such as the central bar, spiral arms, the warp and external satellites. Our results at l=178{deg} are broadly consistent with previous work on K giants in the anticentre, but the kinematics at l=118{deg} in the Perseus region do not yet reconcile easily with bar or spiral arm perturbation.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A51
- Title:
- Overlooked wide companions of nearby F stars
- Short Name:
- J/A+A/587/A51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We checked a sample of 545 F stars within 50pc for wide companions using existing near-infrared and optical sky surveys.
- ID:
- ivo://CDS.VizieR/J/ApJ/817/1
- Title:
- Palomar/MSU and SDSS-DR7 M dwarfs with GALEX obs.
- Short Name:
- J/ApJ/817/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of Galaxy Evolution Explorer Near-UV (NUV) and Far-UV (FUV) photometry for the Palomar/MSU and SDSS DR7 spectroscopic M dwarf catalogs. The catalog contains NUV measurements matched to 577 spectroscopically confirmed M dwarfs and FUV measurements matched to 150 spectroscopically confirmed M dwarfs. Using these data, we find that NUV and FUV luminosities strongly correlate with H{alpha} emission, a typical indicator of magnetic activity in M dwarfs. We also examine the fraction of M dwarfs with varying degrees of strong line emission at NUV wavelengths. Our results indicate that the frequency of M dwarf NUV emission peaks at intermediate spectral types, with at least ~30% of young M4-M5 dwarfs having some level of activity. For mid-type M dwarfs, we show that NUV emission decreases with distance from the Galactic plane, a proxy for stellar age. Our complete matched source catalog is available online.
- ID:
- ivo://CDS.VizieR/J/A+A/419/533
- Title:
- Pal 13 UBV, proper motions and radial velocities
- Short Name:
- J/A+A/419/533
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recently, combining radial velocities from Keck/HIRES echelle spectra with published proper motion membership probabilities, Cote et al. (2002ApJ...574..783C) observed a sample of 21 stars, probable members of Palomar 13, a globular cluster in the Galactic halo. Their projected velocity dispersion sigma_p_=2.2+/-0.4km/s gives a mass-to-light ratio M/L_V_=40^+24^_-17_, about one order of magnitude larger than the usual estimate for globular clusters. We present here radial velocities measured from three different CCD frames of commissioning observations obtained with the new ESO/VLT instrument FLAMES (Fibre Large Array Multi Element Spectrograph). From these data, now publicly available, we measure the homogeneous radial velocities of eight probable members of this globular cluster. A new projected velocity dispersion sigma_p_=0.6-0.9+/-0.3km/s implies Palomar 13 mass-to-light ratio M/L_V_=3-7, similar to the usual value for globular clusters. We discuss briefly the two most obvious reasons for the previous unusual mass-to-light ratio finding: binaries, now clearly detected, and more homogeneous data from the multi-fibre FLAMES spectrograph.
- ID:
- ivo://CDS.VizieR/J/MNRAS/455/4212
- Title:
- Pan-STARRS 1: occurrence in the Kepler field
- Short Name:
- J/MNRAS/455/4212
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The NASA Kepler mission has revolutionized time-domain astronomy and has massively expanded the number of known extrasolar planets. However, the effect of wide multiplicity on exoplanet occurrence has not been tested with this data set. We present a sample of 401 wide multiple systems containing at least one Kepler target star. Our method uses Pan-STARRS 1 and archival data to produce an accurate proper motion catalogue of the Kepler field. Combined with Pan-STARRS 1 SED fits and archival proper motions for bright stars, we use a newly developed probabilistic algorithm to identify likely wide binary pairs which are not chance associations. As byproducts of this we present stellar SED templates in the Pan-STARRS 1 photometric system and conversions from this system to Kepler magnitudes. We find that Kepler target stars in our binary sample with separations above 6arcsec are no more or less likely to be identified as confirmed or candidate planet hosts than a weighted comparison sample of Kepler targets of similar brightness and spectral type. Therefore we find no evidence that binaries with projected separations greater than 3000au affect the occurrence rate of planets with P<300d around FGK stars.
- ID:
- ivo://CDS.VizieR/J/A+A/559/A43
- Title:
- Pan-STARRS1 (PS1) observations of the Hyades
- Short Name:
- J/A+A/559/A43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a kinematic and photometric search for Hyades members using the PPMXL and Pan-STARRS1 sky surveys, up to 30pc from the cluster centre, down to masses of 0.1M_{sun}_. We exclude some candidates previously identified in Roeser et al. (2011, Cat. J/A+A/531/A92). We discovered 62 new Hyades member candidates with velocity perpendicular to the Hyades motion up to 4km/s. They have mass estimates between 0.43 and 0.09M_{sun}_, for a total mass of 10M_{sun}_.