- ID:
- ivo://CDS.VizieR/J/PAZh/38/95
- Title:
- Proper motions and photometry in NGC 2323
- Short Name:
- J/PAZh/38/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a comprehensive study of the Galactic open cluster NGC 2323 are presented. The positions of stars to a limiting magnitude B<=16.7mag in a 42.5x42.5arcmin area centered on the cluster were measured on six plates from the Pulkovo normal astrograph with a maximum epoch difference of 60yr. The measurements were performed with the Pulkovo "Fantasy" automated measuring system upgraded in 2010. The corresponding areas from the USNO-A2.0, USNO-B1, and 2MASS catalogues were used as additional plates. As a result, the relative proper motions of stars were obtained with a root-mean-square error of 5.85mas/yr. A catalogue of UBV and JHK magnitudes for objects in the investigated area was compiled from available published resources. The astrometric selection of cluster members was made by the maximum likelihood method. A high individual cluster membership probability of a star (P>=80%) served as the first selection criterion. The position of a star on the photometric color-magnitude (V-(B-V), J-(J-K)) diagrams of the cluster was considered as the second criterion. The position of an object on the color- color ((U-B)-(B-V), (J-H)-(J-K)) diagrams served as the third criterion. On the basis of these criteria, it was established that 508 stars are members of NGC 2323. These data were used to refine the physical parameters of the cluster: the mean reddening E(B-V)=0.25mag, the true distance modulus (V-M_V_)=9.85mag, and the cluster age of about 140Myr from the grid of isochrones computed by the Padova group for solar chemical composition. Two tables contain the catalogues of proper motions and photometry for stars in the area. The luminosity and mass functions were constructed. The cluster membership of red and blue giants, variable, double, and multiple stars was considered. The position of the cluster center was improved: alpha=07:02:47.5, delta=-08:20:16 (2000.0).
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/543/A87
- Title:
- Proper motions and photometry of stars in M55
- Short Name:
- J/A+A/543/A87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 6809 is a luminous metal-poor halo globular cluster that is relatively easy to study due to its proximity and low concentration. Because of its high Galactic latitude (b=-23{deg}), interstellar reddening and contamination is not very high. We aim to determine the relative proper motion and membership probability of the stars in the wide area of globular cluster NGC 6809. To target cluster members reliably during spectroscopic surveys and both spatial and radial distributions in the cluster outskirts without including field stars, a good proper motion and membership probability catalogue of NGC 6809 is required.
- ID:
- ivo://CDS.VizieR/J/AJ/153/134
- Title:
- Proper motions and photometry of stars in NGC 3201
- Short Name:
- J/AJ/153/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With a high value of heliocentric radial velocity, a retrograde orbit, and suspected to have an extragalactic origin, NGC 3201 is an interesting globular cluster for kinematical studies. Our purpose is to calculate the relative proper motions (PMs) and membership probability for the stars in the wide region of globular cluster NGC 3201. PM based membership probabilities are used to isolate the cluster sample from the field stars. The membership catalog will help address the question of chemical inhomogeneity in the cluster. Archive CCD data taken with a wide-field imager (WFI) mounted on the ESO 2.2m telescope are reduced using the high-precision astrometric software developed by Anderson et al. for the WFI images. The epoch gap between the two observational runs is ~14.3 years. To standardize the BVI photometry, Stetson's secondary standard stars are used. The CCD data with an epoch gap of ~14.3 years enables us to decontaminate the cluster stars from field stars efficiently. The median precision of PMs is better than ~0.8mas/yr for stars having V<18mag that increases up to ~1.5mas/yr for stars with 18<V<20mag. Kinematic membership probabilities are calculated using PMs for stars brighter than V~20mag. An electronic catalog of positions, relative PMs, BVI magnitudes, and membership probabilities in the ~19.7x17arcmin^2^ region of NGC 3201 is presented. We use our membership catalog to identify probable cluster members among the known variables and X-ray sources in the direction of NGC 3201.
- ID:
- ivo://CDS.VizieR/V/27
- Title:
- Proper Motions and UBV Photometry in h+{chi} Per
- Short Name:
- V/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Proper motions with an 80 year baseline have been determined relative to reference stars with B=13.9mag. determined for 3086 stars brighter than B=15.5mag. within an area of 50' radius, centered at RA=2h16.9m, Dec=+57{deg}01' (1950.0). Two pairs of Tashkent normal astrograph plates with a mean epoch difference of 80 years was used. Proper motions were also measured for 1055 stars with 15.5 <= B <= 17.1 mag. in two areas 14' in radius, centered on the h and {chi} Persei clusters. Proper motions are also given for 1386 stars in an adjacent area (RA=2h06.7m, Dec=+56{deg}57') for 1386 stars with a 38 year baseline. The mean errors of the proper motions are equal in right ascension and declination. For the h and {chi} Perseus region, they are 0.0021"/yr and for the adjacent region, they are 0.0031"/yr. The proper motions in the adjacent area have been reduced to the system of those in the cluster region using 214 stars in common. UBV magnitudes of the stars were determined using plates taken with the 80/120/240 Schmidt telescope of the Radioastrophysical Observatory of the Academy of Sciences of the Latvian SSR and photoelectric standards published by Johnson and Morgan (1955ApJ...122..429J) and Widley (1964ApJS....8..439W). The number of measured plates and the corresponding errors are given in the following table: ----------------------------------------------------- FILE NAME # PLATES ERRORS (0.01mag) V B U V B U ----------------------------------------------------- data1.dat 2 3 2 6 5 6 data2.dat 1 2 - 8 6 - adjarea.dat 2 2 2 6 6 6 _____________________________________________________ Cluster members were selected on the basis of their proper motion and photometric criteria. The membership probability was calculated on the assumption of a normal distribution of the proper motions around the cluster proper motion.
2895. Proper motions in M15
- ID:
- ivo://CDS.VizieR/J/ApJ/595/187
- Title:
- Proper motions in M15
- Short Name:
- J/ApJ/595/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an internal proper motion analysis of the inner region of M15 using Hubble Space Telescope Wide Field Planetary Camera 2 images. The motions of 704 stars with brightnesses above that of the cluster turnoff (V<18.3) are analyzed to determine the velocity dispersion profile within about 15" of the cluster center. The average signal-to-noise ratio of these motions is about 3, and stars in the innermost radial bin have an average core distance of only 0.7". Assuming a distance to M15 of 10kpc, we estimate that the velocity dispersion within this innermost bin is 14.5+/-2.5km/s and that it slowly decreases outward, reaching a value of 9.8+/-0.8km/s at R=15.6". We find that the proper-motion dispersion profile is in good agreement with the predictions of recent N-body simulations that do not require the presence of a central intermediate-mass black hole (IMBH). The agreement between the observed profile and the N-body simulations is marginally improved if one assumes that when a neutron star is created as a result of stellar evolution, it escapes from the cluster. Based on the results of this study and a review of other investigations, it is concluded that there is little direct evidence that M15 possesses an intermediate-mass black hole.
- ID:
- ivo://CDS.VizieR/J/A+A/401/531
- Title:
- Proper motions in NGC 7243
- Short Name:
- J/A+A/401/531
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of astrometric and photometric investigations of the open cluster NGC 7243 are presented. Proper motions of 2165 stars with root-mean-square error of 1.1mas/yr were obtained by means of PDS scanning of astrometric plates covering the time interval of 97 years. A total of 211 cluster members down to V=15.5mag have been identified. V and B magnitudes have been determined for 2118 and 2110 stars respectively. Estimations of mass 348M_{sun}_<M<522M_{sun}_, age t=2.510^8^yr, distance r=698pc and reddening E(B-V)=0.24 of the cluster NGC 7243 have been made.
- ID:
- ivo://CDS.VizieR/J/ApJ/710/1032
- Title:
- Proper motions in {omega} Cen
- Short Name:
- J/ApJ/710/1032
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze data from the Hubble Space Telescope's (HST) Advanced Camera for Surveys of the globular cluster (GC) Omega Cen. We construct a photometric catalog of 1.2x10^6^ stars over a 10'x10' central field down to below B_F435W_=25 (M~0.35M_{sun}_). The 2.5 to 4 year baseline between observations yields a catalog of some 10^5^ proper motions over a smaller area, with 53382 "high-quality" measurements in a central R<~2' field. Artificial-star tests characterize the photometric incompleteness. We determine the cluster center to ~1" accuracy from star counts using two different methods, one based on isodensity contours and the other on "pie slices." We independently confirm the result by determining also the kinematical center of the HST proper motions, as well as the center of unresolved light seen in Two Micron All Sky Survey data. All results agree to within their 1"-2" levels of uncertainty. The proper-motion dispersion of the cluster increases gradually inward, but there is no variation in kinematics with position within the central ~15": there is no dispersion cusp and no stars with unusually high velocities. We measure for the first time in any GC the variation in internal kinematics along the main sequence.
- ID:
- ivo://CDS.VizieR/J/A+A/360/472
- Title:
- Proper motions in omega Centauri
- Short Name:
- J/A+A/360/472
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The tables present the photometric and astrometric results of an extensive proper motion study of the globular cluster omega Centauri: information on the photographic plates used, variability analysis, astrometric data for 9847 stars, membership determination and surface density profile, cluster proper motion dispersions and systematics and cross-references with star-numbers used by Norris et al. (1997ApJ...487L.187N) and Lynga (1996A&AS..115..297L).
- 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/ApJ/875/77
- Title:
- Proper motions of MW satellites with Gaia & DES
- Short Name:
- J/ApJ/875/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new, probabilistic method for determining the systemic proper motions of Milky Way (MW) ultra-faint satellites in the Dark Energy Survey (DES). We utilize the superb photometry from the first public data release (DR1) of the DES to select candidate members and cross-match them with the proper motions from the Gaia DR2. We model the candidate members with a mixture model (satellite and MW) in spatial and proper motion space. This method does not require prior knowledge of satellite membership and can successfully determine the tangential motion of 13 DES satellites. With our method, we present measurements of the following satellites: Columba I, Eridanus III, Grus II, Phoenix II, Pictor I, Reticulum III, and Tucana IV. This is the first systemic proper motion measurement for several of these satellites, and the majority lack extensive spectroscopic follow-up studies. We compare these to the predictions of Large Magellanic Cloud satellites and the vast polar structure. With the high-precision DES photometry, we conclude that most of the newly identified member stars are very metal-poor ([Fe/H]<=-2), similar to other ultra-faint dwarf galaxies, while Reticulum III is likely more metal-rich. We also find potential members in the following satellites that might indicate their overall proper motion: Cetus II, Kim 2, and Horologium II. However, due to the small number of members in each satellite, spectroscopic follow-up observations are necessary to determine the systemic proper motion in these satellites.
