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5291. Proper Motions and UBV Photometry in h+{chi} Per
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.
5292. Proper motions in M5
ID:
ivo://CDS.VizieR/J/AJ/106/1524
Title:
Proper motions in M5
Short Name:
J/AJ/106/1524
Date:
21 Oct 2021
Publisher:
CDS
Description:
New proper motions have been derived from reductions of PDS microdensitometer scans of 17 Yerkes refractor plates spanning an epoch range of 88 years for 515 stars down to V~15.6 in the region of the globular cluster M5. Photographic photometry in B and V has been obtained for these stars from these scans and scans of six Yerkes reflector plates. The present proper motions have significantly improved precision compared to Cudworth [AJ, 84, 1866 (1979)]. Membership probabilities derived from the new proper motions are largely in agreement with those from Cudworth's study, but this paper includes nearly 200 additional stars, many of which are probable members. A color-magnitude diagram of probable members is presented and discussed, as well as comparisons to previous photometry. All but two of the previously known or suspected variables are found to be highly probable members. These proper motions have been used by Cudworth & Hanson [AJ, 105, 168 (1993)] to derive a large space velocity for M5, implying that it is a rich outer halo cluster on an eccentric orbit near perigalacticon. These motions will be used in a forthcoming paper to explore the internal dynamics of M5, including a derivation of the cluster distance by comparison of the proper motion and radial velocity dispersions.
5293. 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.
5294. Proper motions in NGC 7243
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.
5295. Proper motions in {omega} Cen
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.
5296. Proper motions in omega Centauri
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).
5297. Proper motions in Plaut's window
ID:
ivo://CDS.VizieR/J/AJ/134/1432
Title:
Proper motions in Plaut's window
Short Name:
J/AJ/134/1432
Date:
21 Oct 2021
Publisher:
CDS
Description:
A proper-motion study of a field of 20'x20' inside Plaut's low-extinction window (l,b) = (0{deg}, -8{deg}) has been completed. Relative proper motions and photographic BV photometry have been derived for ~21000 stars reaching to V~20.5mag, based on the astrometric reduction of 43 photographic plates, spanning over 21yr of epoch difference. Proper-motion errors are typically 1mas/yr, and field-dependent systematics are below 0.2mas/yr. Cross-referencing with the 2MASS catalog yielded a sample of ~8700 stars, from which predominantly disk and bulge subsamples were selected photometrically from the JH color-magnitude diagram. The two samples exhibited different proper-motion distributions, with the disk displaying the expected reflex solar motion as a function of magnitude.
5298. Proper motions near the Baade window
ID:
ivo://CDS.VizieR/J/MNRAS/370/435
Title:
Proper motions near the Baade window
Short Name:
J/MNRAS/370/435
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a proper motion mini-survey of 35 fields in the vicinity of Baade window, (l, b) = (1{deg}, 4{deg}), sampling roughly a 5x2.5deg^2^ region of the Galactic bar. Our second epoch observations collected with the Advanced Camera for Surveys/High Resolution Channel instrument onboard the Hubble Space Telescope were combined with the archival Wide Field Planetary Camera 2/PC images. The resulting time baselines are in the range of 4 to 8yr. Precise proper motions of 15863 stars were determined in the reference frame defined by the mean motion of stars with magnitudes between I_F814W_=16.5 and 21.5 along the line of sight.
5299. Proper motions of IC 2391 possible members
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.
5300. Proper motions of Leo II member stars
ID:
ivo://CDS.VizieR/J/ApJ/741/100
Title:
Proper motions of Leo II member stars
Short Name:
J/ApJ/741/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use 14 year baseline images obtained with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST) to derive a proper motion for one of the Milky Way's most distant dwarf spheroidal companions, Leo II, relative to an extragalactic background reference frame. Astrometric measurements are performed in the effective point-spread function formalism using our own developed code. An astrometric reference grid is defined using 3224 stars that are members of Leo II and brighter than a magnitude of 25 in the F814W band. We identify 17 compact extragalactic sources, for which we measure a systemic proper motion relative to this stellar reference grid. We derive a proper motion [{mu}_{alpha}_,{mu}_{delta}_]=[+104+/-113,-33+/-151]uas/yr for Leo II in the heliocentric reference frame. Though marginally detected, the proper motion yields constraints on the orbit of Leo II. Given a distance of d~230kpc and a heliocentric radial velocity v_r_=+79km/s, and after subtraction of the solar motion, our measurement indicates a total orbital motion v_G_=266.1+/-128.7km/s in the Galactocentric reference frame, with a radial component v_rG_=21.5+/-4.3km/s and tangential component v_tG_=265.2+/-129.4km/s. The small radial component indicates that Leo II either has a low-eccentricity orbit or is currently close to perigalacticon or apogalacticon distance. We see evidence for systematic errors in the astrometry of the extragalactic sources which, while close to being point sources, are slightly resolved in the HST images. We provide a detailed catalog of the stellar and extragalactic sources identified in the HST data which should provide a solid early-epoch reference for future astrometric measurements.