- ID:
- ivo://CDS.VizieR/J/AJ/134/1368
- Title:
- Proper motions in NGC 2244 and NGC 6530
- Short Name:
- J/AJ/134/1368
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We derive the proper motions, membership probabilities, and velocity dispersions of stars in the regions of the young (~2-4Myr old) open clusters NGC 2244 (the central cluster in the Monoceros R2 association) and NGC 6530 (the dominant cluster in the Sgr OB1 association) from photographic plate material obtained at Shanghai Astronomical Observatory, with time baselines of 34 and 87yr, respectively. Both clusters show clear evidence of mass segregation, but they do not exhibit any significant velocity-mass (or, equivalently, velocity-luminosity) dependence.
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Search Results
- ID:
- ivo://CDS.VizieR/I/257B
- Title:
- Proper Motions in Praesepe
- Short Name:
- I/257B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-precision proper motions for 257 and 296 stars in a 90'x90' region centered on BD+20 2170 were obtained from seven plates taken with the Zo-se 40cm refractor (f=6895mm) in March, 1986 (see the "Plate Summary" section below), combined with six AC plates and the stellar positions in Russell's (1976, Ph.D. Thesis, Pittsburgh University). Combined with other data, membership probabilities were estimated by an improved maximum likelihood method. A very good sample of 198 members is obtained with proper motion accuracies ranging from +/-0.2 to +/-5.0mas/yr, of which 60% are better than +/-1.0mas/yr; the completeness limit is about B=15.5mag. Note that the table published in electronic form associated to the paper published in 1995A&AS..113..419W presented positions not correctly associated to the stars (see the "History" section below)
- ID:
- ivo://CDS.VizieR/J/MNRAS/257/257
- Title:
- Proper motions in the Hyades
- Short Name:
- J/MNRAS/257/257
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used COSMOS scans of photographic plates taken by the Palomar Oschin Schmidt telescope (as part of the original Palomar Sky Survey) and by the UK Schmidt telescope to obtain proper motions for ~ 450 000 stars within a 112-degree region covering part of the Hyades cluster. With epoch differences of 33 to 37 yr, we have obtained proper motions accurate to 6-12 mas/yr and have identified 393 candidate Hyads to a limiting magnitude of Mv ~ +15.5, including at least two new white dwarf candidates. The main-sequence luminosity function determined from our sample is similar to that defined by local field stars, with a broad maximum at Mv ~ +12. Deriving distances from mu u, the proper motion towards the convergent point, and the space velocity determined by Gunn et al., we find stars with motions consistent with membership at distances of more than 15pc from the cluster centre. Moreover, both the line-of-sight and surface density distributions show evidence for significant mass segregation - indeed, the overall proper motion distribution suggests a tight core centred within a much broader distribution. We derive a total mass of 410-480Sun and a gravitational binding radius of ~ 10.5pc.
- ID:
- ivo://CDS.VizieR/J/PAZh/23/90
- Title:
- Proper motions in 181 young open clusters
- Short Name:
- J/PAZh/23/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absolute proper motions have been determined for 181 young open clusters based on photometric data and radial velocities of 2980 cluster members.
- ID:
- ivo://CDS.VizieR/J/MNRAS/384/1399
- Title:
- Proper motions of field L and T dwarfs
- Short Name:
- J/MNRAS/384/1399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The proper motion measurements for 142 previously known L and T dwarfs are presented. From this sample we identify and discuss eight high-velocity L dwarfs. We also find four new wide common proper motion binaries/multiple systems. Using the moving cluster methods we have also identified a number of L dwarfs that may be members of the Ursa Major (age~400Myr), the Hyades (age~625Myr) and the Pleiades (age~125Myr) moving groups.
- ID:
- ivo://CDS.VizieR/J/MNRAS/390/1517
- Title:
- Proper motions of field L and T dwarfs
- Short Name:
- J/MNRAS/390/1517
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By using images taken with Wide Field Camera (WFCAM) on United Kingdom Infrared Telescope (UKIRT) and Son of ISAAC (SofI) on the New Technology Telescope (NTT) and combining them with Two Micron All Sky Survey (2MASS) we have measured proper motions for 125 L and T dwarfs in the dwarf archive. Two of these L dwarfs appear to have M dwarf common proper motion companions, and two also appear to be high-velocity dwarfs, indicating possible membership of the thick disc. We have also compared the motion of these 125 objects to that of numerous moving groups, and have identified new members of the Hyades, Ursa Major and Pleiades moving groups. These new objects, as well as those identified in Jameson et al. have allowed us to refine the L dwarf sequence for Ursa Major that was defined by Jameson et al, 2008 (Cat. J/MNRAS/384/1399).
- ID:
- ivo://CDS.VizieR/J/MNRAS/355/959
- Title:
- Proper motions of IC 2391 possible members
- Short Name:
- J/MNRAS/355/959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Large-scale astrometric and photometric data bases have been used to search for and confirm stellar membership of the open cluster IC 2391. 125 stars were found that satisfied criteria for membership based on proper motion components and BRI photometry from the United States Naval Observatory B (USNO-B, Cat. <I/284>) catalogue and JHK photometry from the Two Micron All Sky Survey (2MASS, Cat. <II/246>) catalogue. This listing was compared with others recently published. A distance to the cluster of 147.7+/-5.5pc was found with mean proper motion components, from the Tycho2 catalogue of (-25.04+/-1.53mas/yr; +23.19+/-1.23mas/yr). A revised Trumpler classification of II3r is suggested. Luminosity and mass functions for the candidate stars were constructed and compared with those of field stars and other clusters.
- ID:
- ivo://CDS.VizieR/J/AZh/80/291
- Title:
- Proper motions of open clusters
- Short Name:
- J/AZh/80/291
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The wide neighborhoods of 401 open clusters are analysed using the the modern, high precision, homogeneous all sky ASCC-2.5 all-sky catalogue (Kharchenko, 2001, Cat. <I/280>). More than 28000 possible members (including about 12500 most probable ones) are identified using kinematic and photometric criteria. Star counts with the ASCC-2.5 and USNO-A2.0 (Cat. <I/252>) catalogs are used to determine the angular and linear radii of cluster cores and coronae, which exceed the previous published values by factors of two or three. The mean proper motions are determined directly in the Hipparcos system for 401 open clusters, for 183 of them for the first time. The heliocentric distances of 118 clusters are determined for the first time based on color-magnitude diagrams for the identified members.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A79
- Title:
- Proper motions of open clusters from UCAC4
- Short Name:
- J/A+A/564/A79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of mean proper motions and membership probabilities of individual stars for optically visible open clusters, which have been determined using data from the UCAC4 catalog in a homogeneous way. The mean proper motion of the cluster and the membership probabilities of the stars in the region of each cluster were determined by applying the statistical method in a modified fashion. In this study, we applied a global optimization procedure to fit the observed distribution of proper motions with two overlapping normal bivariate frequency functions, which also take the individual proper motion errors into account. For 724 clusters, this is the first determination of proper motion, and for the whole sample, we present results with a much larger number of identified astrometric member stars. Furthermore, it was possible to estimate the mean radial velocity of 364 clusters (102 unpublished so far) with the stellar membership using published radial velocity catalogs. These results provide an increase of 30% and 19% in the sample of open clusters with a determined mean absolute proper motion and mean radial velocity, respectively.
- ID:
- ivo://CDS.VizieR/J/AZh/80/8
- Title:
- Proper motions of open star clusters
- Short Name:
- J/AZh/80/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The mean proper motions of 390 galactic open clusters with radial-velocity measurements are computed from the data of the Tycho-2 catalog (<I/259>) using the kinematic and photometric cluster membership criteria.
