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- ID:
- ivo://CDS.VizieR/I/121
- Title:
- Common proper motions stars in AGK3
- Short Name:
- I/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 326 common proper motion systems that have a ratio angular separation to proper motion smaller than 1000 years are in table1. The number of optical systems is expected to be around 4. Each system fills a 256 byte-length record that may also be considered as two 128 byte-length records for print-out edition. The 113 common proper motion systems that have a ratio angular separation to proper motion between 1000 and 3500 years are in table2. The number of physical systems is expected to be around 68. The presentation is the same as for table1. This table differs from the original printed version, since the the magnitude and the spectral type of the secondary component of the 47th system were corrected. The system 47 was also added to the notes.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/75
- Title:
- Common proper motion stars in the Kepler field
- Short Name:
- J/ApJ/835/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In a search of proper motion catalogs for common proper motion stars in the field of the Kepler spacecraft I identified 93 likely binary systems. A comparison of their rotation periods is a test of the gyrochronology concept. To find their periods I calculated the autocorrelation function (ACF) of the Kepler mission photometry for each star. In most systems for which good periods can be found, the cooler star has a longer period than the hotter component, in general agreement with models. However, there is a wide range in the gradients of lines connecting binary pairs in a period-color diagram. Furthermore, near the solar color, only a few stars have longer periods than the Sun, suggesting that they, and their cooler companions, are not much older than the Sun. In addition, there is an apparent gap at intermediate periods in the period distribution of the late K and early M stars. Either star formation in this direction has been variable, or stars evolve in period at a non-uniform rate, or some stars evolve more rapidly than others at the same mass. Finally, using the ACF as a measure of the activity level, I found that while the F, G, and early K stars become less active as their periods increase, there is no correlation between period and activity for the mid K to early M stars.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2483
- Title:
- Comoving group associated with HD 141569
- Short Name:
- J/AJ/136/2483
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for a young stellar moving group associated with the star HD 141569 - a nearby, isolated Herbig AeBe primary member of a 5+/-3Myr-old triple star system on the outskirts of the Sco-Cen complex. Our spectroscopic survey identified a population of 21 Li-rich, >~30Myr-old stars within 30{deg} of HD 141569 which possess similar proper motions with the star. The spatial distribution of these Li-rich stars, however, is not suggestive of a moving group associated with the HD 141569 triplet, but rather this sample appears cospatial with Upper Scorpius (US) and Upper Centaurus Lupus (UCL). We apply a modified moving cluster parallax method to compare the kinematics of these youthful stars with those of the US and UCL. Eight new potential members of US and five new potential members of UCL are identified. A substantial moving group with an identifiable nucleus within 15{deg} (~30pc) of HD 141569 is not found in this sample. Evidently, the HD 141569 system formed ~5Myr ago in relative isolation, tens of parsecs away from the recent sites of star formation in the Ophiucus-Scorpius-Centaurus region.
- ID:
- ivo://CDS.VizieR/J/AJ/151/85
- Title:
- Companions to APOGEE stars. I.
- Short Name:
- J/AJ/151/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In its three years of operation, the Sloan Digital Sky Survey Apache Point Observatory Galactic Evolution Experiment (APOGEE-1) observed >14000 stars with enough epochs over a sufficient temporal baseline for the fitting of Keplerian orbits. We present the custom orbit-fitting pipeline used to create this catalog, which includes novel quality metrics that account for the phase and velocity coverage of a fitted Keplerian orbit. With a typical radial velocity precision of ~100-200 m/s, APOGEE can probe systems with small separation companions down to a few Jupiter masses. Here we present initial results from a catalog of 382 of the most compelling stellar and substellar companion candidates detected by APOGEE, which orbit a variety of host stars in diverse Galactic environments. Of these, 376 have no previously known small separation companion. The distribution of companion candidates in this catalog shows evidence for an extremely truncated brown dwarf (BD) desert with a paucity of BD companions only for systems with a<0.1-0.2 AU, with no indication of a desert at larger orbital separation. We propose a few potential explanations of this result, some which invoke this catalog's many small separation companion candidates found orbiting evolved stars. Furthermore, 16 BD and planet candidates have been identified around metal-poor ([Fe/H]<-0.5) stars in this catalog, which may challenge the core accretion model for companions >10 M_Jup_. Finally, we find all types of companions are ubiquitous throughout the Galactic disk with candidate planetary-mass and BD companions to distances of ~6 and ~16 kpc, respectively.
- ID:
- ivo://CDS.VizieR/J/A+A/450/681
- Title:
- Companions to close spectroscopic binaries
- Short Name:
- J/A+A/450/681
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have surveyed a sample of 165 solar-type spectroscopic binaries (SB) with periods from 1 to 30 days for higher-order multiplicity. 62 targets have been observed with the NACO adaptive optics system and 13 new physical tertiary companions were detected. Another 12 new wide companions (5 still tentative) were retrieved from the 2MASS (<II/246>) sky survey. Our binaries belong to 161 stellar systems; of these 64 are triple, 11 quadruple and 7 quintuple. After correction for incomplete detection, the fraction of SBs with additional companions is 63+/-5%. We find that this fraction is a strong function of the SB period P, reaching 96% for P<3d and dropping to 36% for P>12d. Period distributions of SBs with and without tertiaries are significantly different, but their mass ratio distributions are identical. New statistical data on the multiplicity of close SBs indicate that their periods and mass ratios were established very early, but periods of SBs within triples were further shortened by angular momentum exchange with companions.
- ID:
- ivo://CDS.VizieR/J/ApJ/792/119
- Title:
- Companions to nearby stars from Pan-STARRS 1
- Short Name:
- J/ApJ/792/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery of 57 wide (>5'') separation, low-mass (stellar and substellar) companions to stars in the solar neighborhood identified from Pan-STARRS 1 (PS1) data and the spectral classification of 31 previously known companions. Our companions represent a selective subsample of promising candidates and span a range in spectral type of K7-L9 with the addition of one DA white dwarf. These were identified primarily from a dedicated common proper motion search around nearby stars, along with a few as serendipitous discoveries from our Pan-STARRS 1 brown dwarf search. Our discoveries include 23 new L dwarf companions and one known L dwarf not previously identified as a companion. The primary stars around which we searched for companions come from a list of bright stars with well-measured parallaxes and large proper motions from the Hipparcos catalog (8583 stars, mostly A-K dwarfs) and fainter stars from other proper motion catalogs (79170 stars, mostly M dwarfs). We examine the likelihood that our companions are chance alignments between unrelated stars and conclude that this is unlikely for the majority of the objects that we have followed-up spectroscopically. We also examine the entire population of ultracool (>M7) dwarf companions and conclude that while some are loosely bound, most are unlikely to be disrupted over the course of ~10 Gyr. Our search increases the number of ultracool M dwarf companions wider than 300 AU by 88% and increases the number of L dwarf companions in the same separation range by 82%. Finally, we resolve our new L dwarf companion to HIP 6407 into a tight (0.13'', 7.4 AU) L1+T3 binary, making the system a hierarchical triple. Our search for these key benchmarks against which brown dwarf and exoplanet atmosphere models are tested has yielded the largest number of discoveries to date.
- ID:
- ivo://CDS.VizieR/J/A+A/384/145
- Title:
- Compiled catalog of Per OB2 star forming complex
- Short Name:
- J/A+A/384/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Compiled Catalogue (CC) is a photometric and astrometric survey with the center at (RA, DE)_J2000 = (3.86h, 34.6{deg}) and radius of 10 degrees of a nearby region of star formation including the Per OB2 association. The CC is based on recently published astronomical catalogues, e.g. Hipparcos and Tycho-2, and supplemented by relevant astrophysical data from numerous data sources. The CC is complete down to V=11.6mag, in general, and to V=18.5mag in the one square degree field with the IC 348 cluster. The coordinates and proper motions are reduced to the Hipparcos system and the photometry in the Johnson system. Typical accuracies of 1-20mas for coordinates, 1-3mas/yr for proper motions, 0.01-0.05mag for BV magnitudes were achieved for majority of 29452 CC stars (V<12mag). For a large number of stars we also collected parallaxes and spectral classes (about 7000 stars), the R (about 2000 stars), I, J, H, K (about 500 stars) magnitudes, radial velocities (330 stars). Stars in the Compiled Catalogue are sorted in right ascension order.
- ID:
- ivo://CDS.VizieR/J/A+A/384/925
- Title:
- Compiled catalog of stellar data of Miras
- Short Name:
- J/A+A/384/925
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Compiled Catalogue of Mira variables is a result of a merge of the 4th edition of the General Catalogue of Variable Stars (GCVS-4) <II/214A> and present-day high-precision catalogues of space (Hipparcos-Tycho family: Hipparcos <I/239>, Tycho-1 <I/239>, Tycho-2 <I/259>, ACT RC <I/246>, TRC <I/250>) and ground-based (CMC11 <I/256>, PPM-N <I/146>, PPM-S <I/193>, PPM-add <I/208>, Kharchenko 1992) data. The catalogue contains 1103 Miras. Equatorial coordinates were taken from the source catalogues in accordance with the priority: Hipparcos, Tycho-2, Tycho-1, CMC11, PPM, Kharchenko 1992. The proper motions of 1041 Miras are calculated as mean weighted values of source data reduced to the Hipparcos system. The radial velocities of 786 Miras were taken from nine catalogues and lists of Feast (1963MNRAS.125..367F, 1966MNRAS.132..495F), Smak and Preston (1965ApJ...142..943S), Perry and Bidelman (1965PASP...77..214P), Feast et al. (1972MNRAS.158...23F), Dean (1976AJ.....81..364D), Barnes and Fekel (1977Obs....97....1B), Feast et al. (1980MNRAS.190..227F), Barbier-Brossat and Figon (2000) <III/213>, and are given with respect of the absorption lines. For those radial velocities, which were determined from emission lines the correction has been made along with Ikaunieks (1971) relation: VR(abs) - VR(em) = 0.035 * Period. For 724 Miras both proper motions and radial velocities are available. The stars in the Compiled Catalogue are sorted in the same order as in the General Catalogue of Variable Stars.
- ID:
- ivo://CDS.VizieR/J/AJ/158/187
- Title:
- Confirmed members of nearby young moving groups
- Short Name:
- J/AJ/158/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first statistical analysis of exoplanet direct imaging surveys combining adaptive optics (AO) imaging at small separations with deep seeing-limited observations at large separations allowing us to study the entire orbital separation domain from 5 to 5000 au simultaneously. Our sample of 344 stars includes only confirmed members of nearby young associations and is based on all AO direct-imaging detection limits readily available online, with addition of our own previous seeing-limited surveys. Assuming that the companion distribution in mass and a semimajor axis follows a power-law distribution and adding a dependence on the mass of the host star, such as d^2^{prop.to}fM^{alpha}^a^{beta}^(M_*_/M_{sun}_)^{gamma}^dMda, we constrain the parameters to obtain {alpha}=-0.18_-0.65_^+0.77^, {beta}=-1.43_-0.24_^+0.23^, and {gamma}=0.62_-0.50_^+0.56^ at a 68% confidence level, and we obtain f=0.11_-0.05_^+0.11^ for the overall planet occurrence rate for companions with masses between 1 and 20 M_Jup_ in the range of 5-5000 au. Thus, we find that occurrence of companions is negatively correlated with a semimajor axis and companion mass (marginally) but is positively correlated with the stellar host mass. Our inferred mass distribution is in good agreement with other distributions found previously from direct imaging surveys for planets and brown dwarfs, but is shallower as a function of mass than the distributions inferred by radial velocity surveys of gas giants in the 1-3 au range. This may suggest that planets at these wide and very wide separations represent the low-mass tail of the brown dwarfs and stellar companion distribution rather than an extension of the distribution of the inner planets.
