- ID:
- ivo://CDS.VizieR/J/MNRAS/470/3937
- Title:
- 1876 open clusters multimembership catalog
- Short Name:
- J/MNRAS/470/3937
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The main objective of this work is to determine the cluster members of 1876 open clusters, using positions and proper motions of the astrometric fourth United States Naval Observatory (USNO) CCD Astrograph Catalog (UCAC4). For this purpose, we apply three different methods, all based on a Bayesian approach, but with different formulations: a purely parametric method, another completely non-parametric algorithm and a third, recently developed by Sampedro & Alfaro (2016MNRAS.457.3949S), using both formulations at different steps of the whole process. The first and second statistical moments of the members' phase-space subspace, obtained after applying the three methods, are compared for every cluster. Although, on average, the three methods yield similar results, there are also specific differences between them, as well as for some particular clusters. The comparison with other published catalogues shows good agreement. We have also estimated, for the first time, the mean proper motion for a sample of 18 clusters. The results are organized in a single catalogue formed by two main files, one with the most relevant information for each cluster, partially including that in UCAC4, and the other showing the individual membership probabilities for each star in the cluster area. The final catalogue, with an interface design that enables an easy interaction with the user, is available in electronic format at the Stellar Systems Group (SSG-IAA) web site (http://ssg.iaa.es/en/content/sampedro-cluster-catalog).
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/105/1822
- Title:
- Open clusters near eta Car
- Short Name:
- J/AJ/105/1822
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Proper motions and photographic photometry have been derived for nearly 600 stars with 7.5 < V < 15.5 in the region of the very young open clusters Tr 14, Tr 16, and Cr 232 based on 26 plates dating from 1893 to 1990. Cluster membership probabilities have been derived from the proper motions and color-magnitude diagrams of probable members of each cluster are presented. In contrast to a few of the previous studies we find all three clusters to lie at the same distance.
- ID:
- ivo://CDS.VizieR/J/A+A/652/A102
- Title:
- 3794 open clusters parameters
- Short Name:
- J/A+A/652/A102
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The structure and evolution of the spiral arms of the Milky Way are basic but long-standing questions in astronomy. Especially the lifetime of spiral arms, it is still a puzzle and has not been well constrained from observations. In this work, we aim to inspect these issues by using a large catalogue of open clusters. We have compiled a catalogue of 3794 OCs based on Gaia EDR3. A majority of them have accurately determined parallaxes, proper motions and radial velocities. The age parameters for these OCs are also collected or calculated. Then, we analysed their distributions on the Galactic plane, the kinematic properties, the vertical distributions and the regressed properties of subsamples of OCs in order to better understand the nearby spiral structure and its evolution. We find evidence that the nearby spiral arms are compatible with a long lived pattern and might have remained approximately stable for the past 80 million years. Especially, the Local Arm where our Sun is currently located in, is also suggested to be long-lived in nature, and probable a major arm segment in the Milky Way. The evolutionary characteristics of nearby spiral arms show that the dynamic spiral mechanism might be not suitable for our Galaxy. Instead, the density wave theory is more consistent with the observational properties.
- ID:
- ivo://CDS.VizieR/J/A+A/446/949
- Title:
- Open clusters proper motions based on UCAC2
- Short Name:
- J/A+A/446/949
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the kinematics of hundreds of open clusters, based on the UCAC2 Catalogue positions and proper motions. Membership probabilities were obtained for the stars in the cluster fields by applying a statistical method uses stellar proper motions. All open clusters with known distance were investigated, and for 75 clusters this is the first determination of the mean proper motion. The results, including the DSS images of the cluster's fields with the kinematic members marked, are incorporated in the Open Clusters Catalogue supported on line by our group.
- ID:
- ivo://CDS.VizieR/J/A+A/523/A11
- Title:
- Open clusters towards the Galactic center
- Short Name:
- J/A+A/523/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the framework of the study of the Galactic metallicity gradient and its time evolution, we present new high-resolution spectroscopic observations obtained with FLAMES and the fiber link to UVES at VLT of three open clusters (OCs) located within ~7kpc from the Galactic Center (GC): NGC 6192, NGC 6404, NGC 6583. We also present new orbit determination for all OCs with Galactocentric distances (R_gc_)<=8kpc and metallicity from high-resolution spectroscopy. We have derived memberships of a group of evolved stars for each clusters, obtaining a sample of 4, 4, and 2 member stars in NGC 6192, NGC 6404, and NGC 6583, respectively. Using standard LTE analysis we derived stellar parameters and abundance ratios for the iron-peak elements Fe, Ni, Cr, and for the {alpha}-elements Al, Mg, Si, Ti, Ca. We calculated the orbits of the OCs currently located within 8kpc from the GC, and discuss their implication on the present-time radial location. The average metallicities of the three clusters are all oversolar: [Fe/H]= +0.12+/-0.04 (NGC 6192), +0.11+/-0.04 (NGC 6404), +0.37+/-0.03 (NGC 6583). They are in qualitative agreement with their galactocentric distances, being all internal OCs, and thus expected to be metal richer than the solar neighborhood. The abundance ratios of the other elements over iron [X/Fe] are consistent with solar values. The clusters we have analysed, together with other OC and Cepheid data, confirm a steep gradient in the inner disk, a signature of an evolutionary rate different than in the outer disk.
- ID:
- ivo://CDS.VizieR/J/A+A/637/A95
- Title:
- 16 open clusters UBVI and Gaia DR2 photometry
- Short Name:
- J/A+A/637/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper has two main objectives: (1) To determine the intrinsic properties of sixteen faint and mostly unstudied open clusters in the poorly known sector of the Galaxy at 270{deg}-300{deg}, to probe the Milky Way structure in future investigations. (2) To address previously reported systematics in Gaia DR2 parallaxes by comparing the cluster distances derived from photometry with those derived from parallaxes. Deep UBVI photometry of 16 open clusters was carried out. Observations were reduced and analyzed in an automatic way using the ASteCA package to get individual distances, reddening, masses, ages and metallicities. Photometric distances were compared to those obtained from a Bayesian analysis of Gaia DR2 parallaxes. Ten out of the sixteen clusters are true or highly probable open clusters. Two of them are quite young and follow the trace of the Carina Arm and the already detected warp. The rest of the clusters are placed in the interarm zone between the Perseus and Carina Arms as expected for older objects. We found that the cluster van den Berg-Hagen 85 is 7.5x10^9^yrs old becoming then one of the oldest open cluster detected in our Galaxy so far. The relationship of these ten clusters with the Galaxy structure in the solar neighborhood is discussed. The comparison of distances from photometry and parallaxes data, in turn, reveals a variable level of disagreement. Various zero point corrections for Gaia DR2 parallax data recently reported were considered for a comparison between photometric and parallax based distances. The results tend to improve with some of these corrections. Photometric distance analysis suggest an average correction of ~+0.026mas (to be added to the parallaxes). The correction may have a more intricate distance dependency, but addressing that level of detail will require a larger cluster sample.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A116
- Title:
- Open clusters within 1.8 kpc of the Sun
- Short Name:
- J/A+A/593/A116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on an almost complete sample of Galactic open star clusters within 1.8kpc, we perform a comprehensive statistical analysis of various cluster parameters like spatial position, age, size, mass and extinction in order to understand the general properties of the open cluster system in the Galaxy and the Galactic structure. Based on the distribution of 1241 open clusters about the Galactic plane and in different age bins, we find the average Galactic scale height as Zh=60+/-2pc for the youngest cluster population having Age<700Myr, however, it increases up to 64+/-2pc when we also include older population of clusters. The solar offset is found to be 6.2+/-1.1pc above the formal Galactic plane. We derive a local mass density of {rho}_0_=0.090+/-0.005M_{sun}_/pc^3^ and found a negligibly small amount of dark matter in the solar neighbourhood. The reddening in the direction of clusters suggests a strong correlation with their vertical distance from the Galactic plane having a respective slope of dE(B-V)/dz=0.40+/-0.04 and 0.42+/-0.05 mag/kpc below and above the GP. We observe a linear mass-radius and mass-age relations in the open clusters and derive a slope of dR/d(logM)=2.08+/-0.10 and d(logM)/d(logT)=-0.36+/-0.05,respectively.
768. Open cluster TR 10
- ID:
- ivo://CDS.VizieR/I/216A
- Title:
- Open cluster TR 10
- Short Name:
- I/216A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Positions for 979 stars in the area of Tr 10 are derived from fifteen plates taken recently with the ICDA refractor. For the determination of proper motions nine plates of the Cape Astrographic Catalogue are used as first epoch. The results make it appear doubtful that the object is a single cluster.
- ID:
- ivo://CDS.VizieR/J/A+A/640/A9
- Title:
- Open star cluster Coma Berenices multi-photometry
- Short Name:
- J/A+A/640/A9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We mainly aim to search for the lithium depletion boundary (LDB) among the sub-stellar population of the open star cluster Coma Berenices. Since the number of brown dwarf candidates in Coma Ber available in the literature is scarce, we carried out a search for additional candidates photometrically using colour-magnitude diagrams combining optical and infrared photometry from the latest public releases of the following large-scale surveys: the United Kingdom InfraRed Telescope Infrared Deep Sky Survey (UKIRT/UKIDSS), the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), the Sloan Digital Sky Survey (SDSS), and AllWISE. We checked astrometric consistency with cluster membership using Gaia DR2. A search for Li in three new and five previously known brown dwarf candidate cluster members was performed via spectroscopic observations using the OSIRIS instrument at the 10.4m Gran Telescopio de Canarias (GTC). A couple dozen new photometric candidate brown dwarfs located inside the tidal radius of Coma Ber are reported, but none of these are significantly fainter and cooler than previously known members. No LiI resonance doublet at 6707.8{AA} was detected in any of eight Coma Ber targets in the magnitude range J=15-19 and G=20-23 observed with the GTC. Spectral types and radial velocities were derived from the GTC spectra. These values confirm the cluster membership of four L2-L2.5 dwarfs, two of which are new in the literature. The large Li depletion factors found among the four bona fide sub-stellar members in Coma Ber implies that the LDB must be located at spectral type later than L2.5 in this cluster. Using the latest evolutionary models for brown dwarfs, a lower limit of 550Myr on the cluster age is set. This constraint has been combined with other dating methods to obtain an updated age estimate of 780+/-230Myr for the Coma Ber open cluster. Identification of significantly cooler sub-stellar cluster members in Coma Ber awaits the advent of the Euclid wide survey, which should reach a depth of about J=23; this superb sensitivity will make it possible to determine the precise location of the sub-stellar LDB in this cluster and to carry out a complete census of its sub-stellar population.
- ID:
- ivo://CDS.VizieR/J/A+A/369/511
- Title:
- Open star clusters. III. NGC 4103, 5281, 4755
- Short Name:
- J/A+A/369/511
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Tables 5, 7, and 8 contain the data of the CCD photometry of the three open star clusters. We added the numbering systems of previously published papers to the tables. Table 5 contains the data of NGC 4103 with stellar numbers from Wesselink (1969MNRAS.146..329W); Table 7 the data of NGC 5281 with the numbers of Moffat & Vogt (1973A&AS...10..135M); Table 8 the data of NGC 4755 with the numbering system according to Arp & van Sant (1958AJ.....63..341A). In Tables 12, 13, and 14 we present relative proper motions of the three clusters (in the same sequence). For NGC 4103 the table contains the information of an entire Carte du Ciel field of 2 degrees square, for the other two clusters, a small subfield had to be selected beforehand. The numbers of Arp & van Sant (1958AJ.....63..341A) are encrypted in the following way: Numbers <100 stand for the stars A to Q, the first digit of the numbers >100 represents the quadrant. The two final digits are the running numbers in the notation of Arp & van Sant (1958AJ.....63..341A).
