- ID:
- ivo://CDS.VizieR/J/MNRAS/453/106
- Title:
- NGC5617 and Trumpler 22 stars BV mag and RV
- Short Name:
- J/MNRAS/453/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using photometry and high-resolution spectroscopy we investigate for the first time the physical connection between the open clusters NGC 5617 and Trumpler 22. Based on new CCD photometry we report their spatial proximity and common age of ~70Myr. Based on high-resolution spectra collected using the HERMES and UCLES spectrographs on the Anglo-Australian telescope, we present radial velocities and abundances for Fe, Na, Mg, Al, Si, Ca, and Ni. The measured radial velocities are -38.63+/-2.25km/s for NGC 5617 and -38.46+/-2.08km/s for Trumpler 22. The mean metallicity of NGC 5617 was found to be [Fe/H]=-0.18+/-0.02 and for Trumpler 22 was found to be [Fe/H]=-0.17+/-0.04. The two clusters share similar abundances across the other elements, indicative of a common chemical enrichment history of these clusters. Together with common motions and ages we confirm that NGC 5617 and Trumpler 22 are a primordial binary cluster pair in the Milky Way.
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- ID:
- ivo://CDS.VizieR/J/AJ/122/1486
- Title:
- NGC 2451A proper motions and membership
- Short Name:
- J/AJ/122/1486
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide new evidence that NGC 2451A is undoubtedly a young open cluster, although sparsely populated. New cluster membership has been derived from relative proper motions of 5868 stars. In total, 136 stars down to V~15 5 have membership probability P{mu}>=2%. New CCD BV photometry indicates that about 70 stars are indeed main-sequence stars of NGC 2451A. This is also supported by our measurements of radial velocities. A total of 34 very likely cluster members yield a mean heliocentric radial velocity for NGC 2451A equal to +22.9km/s. The high quality of our BV photometry, a confirmation of cluster membership from proper motions and radial velocities, and a recently obtained metallicity estimate for several cluster stars allow us to perform a precise isochrone fit. The Yale isochrones, updated by the latest available input physics, have been fitted to the cluster's color-magnitude diagram, yielding a distance modulus V_0_-M_V_ in the range 6.35 to 6.38, which is in excellent agreement with the distance modulus (m-M)_0_=6.38 derived from the Hipparcos data recently by van Leeuwen and Robichon et al. (1998, Cat. <J/A+AS/130/157>). We have used the high-resolution spectra acquired using the Hydra multiobject spectrograph at the WIYN telescope (Kitt Peak, Arizona) in 1997 November and 1998 October.
- ID:
- ivo://CDS.VizieR/J/MNRAS/454/3597
- Title:
- NGC 2282 BVI Ha observations
- Short Name:
- J/MNRAS/454/3597
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of the stellar content of NGC 2282, a young cluster in the Monoceros constellation, using deep optical BVI and INT Photometric H{alpha} Survey (IPHAS) photometry along with infrared (IR) data from UKIRT Infrared Deep Sky Survey and Spitzer-IRAC. Based on the stellar surface density analysis using nearest neighbourhood method, the radius of the cluster is estimated as ~3.15-arcmin. From optical spectroscopic analysis of eight bright sources, we have classified three early B-type members in the cluster, which includes, HD 289120, a previously known B2V-type star, a Herbig Ae/Be star (B0.5 Ve) and a B5 V star. From spectrophotometric analyses, the distance to the cluster has been estimated as ~1.65kpc. The K-band extinction map is estimated using nearest neighbourhood technique, and the mean extinction within the cluster area is found to be A_V_~3.9mag. Using IR colour-colour criteria and H{alpha}-emission properties, we have identified a total of 152 candidate young stellar objects (YSOs) in the region, of which, 75 are classified as Class II, nine are Class I YSOs. Our YSO catalogue also includes 50 H{alpha}-emission line sources, identified using slitless spectroscopy and IPHAS photometry data. Based on the optical and near-IR colour-magnitude diagram analyses, the cluster age has been estimated to be in the range of 2-5Myr, which is in agreement with the estimated age from disc fraction (~58 per cent). Masses of these YSOs are found to be ~0.1-2.0M_{sun}_. Spatial distribution of the candidate YSOs shows spherical morphology, more or less similar to the surface density map.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/4185
- Title:
- NGC 2355 BVI photometry
- Short Name:
- J/MNRAS/453/4185
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we analyse the evolutionary status and properties of the old open cluster NGC 2355, located in the Galactic anticentre direction, as a part of the long-term programme Bologna Open Clusters Chemical Evolution. NGC 2355 was observed with the Large Binocular Camera at the Large Binocular Telescope using the Bessel B, V, and Ic filters. The cluster parameters have been obtained using the synthetic colour-magnitude diagram method, as done in other papers of this series. Additional spectroscopic observations with the Fibre-fed Echelle Spectrograph at the Nordic Optical Telescope of three giant stars were used to determine the chemical properties of the cluster. Our analysis shows that NGC 2355 has metallicity slightly less than solar, with [Fe/H]=-0.06dex, age between 0.8 and 1Gyr, reddening E(B-V) in the range 0.14-0.19mag, and distance modulus (m-M)0 of about 11mag. We also investigate the abundances of O, Na, Al, {alpha}, iron-peak, and neutron capture elements, showing that NGC 2355 falls within the abundance distribution of similar clusters (same age and metallicity). The Galactocentric distance of NGC 2355 places it at the border between two regimes of metallicity distribution; this makes it an important cluster for the study of the chemical properties and evolution of the disc.
- ID:
- ivo://CDS.VizieR/J/A+A/583/A69
- Title:
- NGC 6139 BV photometry
- Short Name:
- J/A+A/583/A69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Information on globular clusters (GC) formation mechanisms can be gathered by studying the chemical signature of the multiple populations that compose these stellar systems. In particular, we investigate the anti-correlations among O, Na, Al, and Mg to explore the influence of cluster mass and environment on GCs in the Milky Way and in extragalactic systems. We present here the results obtained on NGC 6139, which, on the basis of its horizontal branch morphology, has been proposed to be dominated by first-generation stars. In our extensive study based on high-resolution spectroscopy, the first for this cluster, we found a metallicity of [Fe/H]=-1.579+/-0.015+/-0.058 (rms=0.040dex, 45 bona fide member stars) on the UVES scale defined by our group. The stars in NGC 6139 show a chemical pattern normal for GCs, with a rather extended Na-O (and Mg-Al) anticorrelation. NGC 6139 behaves as expected from its mass and contains a large portion (about two thirds) of second-generation stars.
- ID:
- ivo://CDS.VizieR/J/PASP/117/22
- Title:
- NGC 6318 CCD BVI photometry
- Short Name:
- J/PASP/117/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD BVI photometry for the southern open cluster NGC 6318. The sample consists of 9876 stars measured in an area of 13.6'x13.6', extending down to V~21.5mag. Star counts carried out within and outside the cluster region allowed us to estimate the cluster angular radius as 8'.
- ID:
- ivo://CDS.VizieR/J/A+A/355/138
- Title:
- NGC 6994 CCD photometry
- Short Name:
- J/A+A/355/138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- BVRI CCD photometry of 144 stars in the region of NGC 6994: positions, V magnitudes, (B-V), (V-R) and (V-I) colors.
- ID:
- ivo://CDS.VizieR/J/other/ApSS/361.126
- Title:
- NGC 6819 CCD UBV photometry
- Short Name:
- J/other/ApSS/361
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of CCD UBV observations of the open cluster NGC 6819. We calculated the stellar density profile in the cluster's field to determine the structural parameters of NGC 6819. Using the existing astrometric data, we calculated the probabilities of the stars being physical members of the cluster, and used these objects in the determination of the astrophysical parameters of NGC 6819. We inferred the reddening and metallicity of the cluster as E(B-V)=0.130+/-0.035mag and [Fe/H]=+0.051+/-0.020dex, respectively, using the U-B vs B-V two-colour diagram and UV excesses of the F-G type main-sequence stars. We fit the colour-magnitude diagrams of NGC 6819 with the PARSEC isochrones and derived the distance modula, distance and age of the cluster as mu_V=12.22+/-0.10mag, d=2309+/-106pc and t=2.4+/-0.2Gyr, respectively. The parameters of the galactic orbit estimated for NGC 6819 indicate that the cluster is orbiting in a slightly eccentric orbit of e=0.06 with a period of P_orb_=142Myr. The slope of the mass function estimated for the cluster is close to the one found for the stars in the solar neighbourhood.
- ID:
- ivo://CDS.VizieR/J/other/ApSS/355.267
- Title:
- NGC 6811 CCD UBVRI photometry
- Short Name:
- J/other/ApSS/355
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of CCD UBVRI observations of the open cluster NGC 6811 obtained on 18th July 2012 with the 1m telescope at the TIBITAK National Observatory (TUG). Using these photometric results, we determine the structural and astrophysical parameters of the cluster. The mean photometric uncertainties are better than 0.02 mag in the V magnitude and B-V, V-R, and V-I colour indices to about 0.03mag for U-B among stars brighter than magnitude V=18. Cluster member stars were separated from the field stars using the Galaxia model of Sharma et al. (2011ApJ...730....3S) together with other techniques. The core radius of the cluster is found to be r_c_=3.60arcmin. The astrophysical parameters were determined simultaneously via Bayesian statistics using the colour-magnitude diagrams V versus B-V, V versus V-I, V versus V-R, and V versus R-I of the cluster. The resulting most likely parameters were further confirmed using independent methods, removing any possible degeneracies. The colour excess, distance modulus, metallicity and the age of the cluster are determined simultaneously as E(B-V)=0.05+/-0.01mag, {mu}=10.06+/-0.08mag, [M/H]=-0.10+/-0.01dex and t=1.00+/-0.05Gyr, respectively. Distances of five red clump stars which were found to be members of the cluster further confirm our distance estimation.
- ID:
- ivo://CDS.VizieR/J/A+AS/134/525
- Title:
- NGC 6611 compiled catalog
- Short Name:
- J/A+AS/134/525
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains data on stars in sky area of the open cluster NGC 6611. The catalogue is based on a new reduction of positions, proper motions, and photometric data whenever published in this region and includes among others, Hipparcos, AC/GSC and Tautenburg Schmidt plate observations. The basis of compiled catalogue is made of stars distributed over a circular area with radius of 22.8arcmin centered on the cluster NGC 6611 (Kharchenko and Schilbach, 1995AN....316...91K). To construct the compiled catalogue, we used also astrometric data published by Van Schewick (1962VeUSB..62....1V), Kamp (1974A&AS...16....1K), Tucholke et al. (1986A&AS...66..311T), Bastian and Roeser (1993, Cat. <I/193>), Roeser (1996, in "An updated GSC as the astrometric reference for minor planet observations", Kluwer Dordrecht, p. 481.), Hillenbrand et al. (1993, Cat. <J/AJ/106/1906>), and photometry published by Walker (1961ApJ...133..438W), Hoag et al. (1961PUSNO..17..343H), Hiltner and Morgan (1969AJ.....74.1152H), Sagar and Joshi (1979Ap&SS..66....3S), The et al (1990A&AS...82..319T), Hillenbrand et al. (1993, Cat. <J/AJ/106/1906>) as it described by Belikov et al. (1998, A&A, in press, this paper, 1999A&AS..134..525B). The catalogue contains 2185 stars up to the limiting magnitudes V=16.78mag. It includes equatorial (equinox 2000.0 and epoch 1990.77) and rectangular coordinates, absolute proper motions with respect to the Hipparcos proper motion system, photometric data (results of UBV, HJK photometry and color excess) and cluster membership probabilities. X - and Y - directions correspond to right ascension and declination directions. The rms errors of right ascension and declination are 0.008sec and 0.14arcsec, respectively. The individual rms errors of proper motions and V-magnitudes are given in the catalogue. The membership probabilities of the cluster stars belonging to the core and corona were determined using information both on spatial and proper motion distributions of stars in the field.
