- ID:
- ivo://CDS.VizieR/J/A+A/476/199
- Title:
- Trumpler 14 JHKL' photometry
- Short Name:
- J/A+A/476/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the deepest and highest resolution near-infrared imaging to date of cluster Trumpler 14 in Carina. Our goal is to identify and characterise the young stellar population of this massive cluster. We made use of deep and wide-field NIR images from NTT and VLT observations, that were sensitive enough to detect substellar sources at the distance to this cluster, and at high enough resolution (VLT diffraction limited) to fully resolve the core of the cluster crowded with O stars.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/446/1411
- Title:
- Trumpler 5 photometric BV catalog
- Short Name:
- J/MNRAS/446/1411
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of a long-term programme, we analyse the evolutionary status and properties of the old and populous open cluster Trumpler 5 (Tr 5), located in the Galactic anticentre direction, almost on the Galactic plane. Tr 5 was observed with Wide Field Imager@MPG/ESO Telescope using the Bessel U, B, and V filters. The cluster parameters have been obtained using the synthetic colour-magnitude diagram (CMD) method, i.e. the direct comparison of the observational CMD with a library of synthetic CMDs generated with different stellar evolution sets (Padova, FRANEC, and FST). Age, reddening, and distance are derived through the synthetic CMD method using stellar evolutionary models with subsolar metallicity (Z=0.004 or Z=0.006). Additional spectroscopic observations with Ultraviolet VLT Echelle Spectrograph@Very Large Telescope of three red clump stars of the cluster were used to determine more robustly the chemical properties of the cluster. Our analysis shows that Tr 5 has subsolar metallicity, with [Fe/H]=-0.403+/-0.006 dex (derived from spectroscopy), age between 2.9 and 4 Gyr (the lower age is found using stellar models without core overshooting), reddening E(B-V) in the range 0.60-0.66 mag complicated by a differential pattern (of the order of ~+/-0.1mag), and distance modulus (m-M)_0_=12.4+/-0.1mag.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A47
- Title:
- U-band photometry in sigma Orionis region
- Short Name:
- J/A+A/525/A47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the results of an U band survey with FORS1/VLT of a large area in the sigma Ori star-forming region. We combine the U-band photometry with literature data to compute accretion luminosity and mass accretion rates from the U-band excess emission for all objects (187) detected by Spitzer in the FORS1 field and classified by Hernandez et al. (2007, Cat. J/ApJ/662/1067) as likely members of the cluster.
- ID:
- ivo://CDS.VizieR/J/AJ/115/1076
- Title:
- UBRVI photometry of Collinder 110
- Short Name:
- J/AJ/115/1076
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of photoelectric UBVRI photometry of 78 stars and photographic PDS and CCD photometry for 437 stars are presented for Collinder 110, an old open cluster at low Galactic latitude. Proper motions obtained from Lick Sky Survey plates were used to identify 39 stars as foreground objects. The cluster's reddening, distance, and age are estimated as E(B-V)=0.50+/-0.03mag, r=1950+/-300pc, and t=1.4+/-0.3Gyr, assuming a solar metal abundance.
- ID:
- ivo://CDS.VizieR/II/124A
- Title:
- UBV and MK types in Open Clusters, 3rd ed.
- Short Name:
- II/124A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- See the complete documentation written by Anne C. Raugh (file adc.doc)
- ID:
- ivo://CDS.VizieR/J/A+A/423/189
- Title:
- UBV and RV of red giants in NGC 2477
- Short Name:
- J/A+A/423/189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New, accurate radial velocities and photoelectric UBV photometry of 83 red-giant candidates in the field of the rich, intermediate-age open cluster NGC 2477 ([Fe/H]=-0.05, age ~1Gyr) are presented and discussed. From 49 constant-velocity members we find a mean cluster velocity of +7.32+/-0.13km/s and confirm the membership of 76 of the stars. Among the cluster members, we identify 26 definite and 1 probable spectroscopic binaries and determine orbits for 13 of these systems, with periods ranging from 40 to 4578 days. The binary frequency is thus rather high (27/76=36%). The observed internal radial velocity dispersion of the cluster, as determined from the single member stars, is 0.93km/s, corrected for the small average observational error of 0.22km/s. Fitting King-type models to the observed stellar density distribution and velocity dispersion, and assuming a distance of 1.25kpc, we find the core and tidal radii of NGC 2477 to be 1.8 and 8.1pc, respectively, and estimate that the mass of cluster stars down to V=17, corresponding to ~1M_{sun}_, is at least 5400 M_{sun}_. The substantial differential reddening of NGC 247 requires a more detailed study before definitive isochrone fits can be made.
- ID:
- ivo://CDS.VizieR/J/A+AS/76/101
- Title:
- UBV and uvbyb in zeta Scl cluster
- Short Name:
- J/A+AS/76/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 130 stars in the region of the Zeta Sculptoris cluster have been observed photoelectrically, most of them in UBVBeta and about half of them in uvby and a few also in the Cousins' system.
- ID:
- ivo://CDS.VizieR/J/A+A/391/179
- Title:
- UBV CCD photometry of NGC 1220
- Short Name:
- J/A+A/391/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UBV CCD observations obtained in the field of the northern open cluster NGC 1220, for which little information is available. We provide also BV CCD photometry of a field 5' northward of NGC 1220 to take into account field star contamination. We argue that NGC 1220 is a young compact open cluster, for which we estimate a core radius in the range 1.5-2.0arcmin. We identify 26 likely candidate members with spectral type earlier than A5, down to V_0_=15.00mag on the basis of the position in the two-colour Diagram and in the Colour Magnitude Diagrams (CMDs). By analyzing the distribution of these stars in the colour-colour and CMDs, we find that NGC 1220 has a reddening E(B-V)=0.70+/-0.15mag, is placed 1800+/-200pc distant from the Sun, and has an age of about 60Myrs. The cluster turns out to be located about 120pc above the Galactic plane, relatively high with respect to its age.
- ID:
- ivo://CDS.VizieR/J/AJ/145/37
- Title:
- UBVI and H{alpha} CCD photometry of NGC 6231
- Short Name:
- J/AJ/145/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed new wide-field photometry of the young open cluster NGC6231 to study the shape of the initial mass function (IMF) and mass segregation. We also investigated the reddening law toward NGC6231 from optical to mid-infrared color excess ratios, and found that the total-to-selective extinction ratio is R_V_=3.2, which is very close to the normal value. But many early-type stars in the cluster center show large color excess ratios. We derived the surface density profiles of four member groups, and found that they reach the surface density of field stars at about 10', regardless of stellar mass. The IMF of NGC6231 is derived for the mass range 0.8-45M_{sun}_. The slope of the IMF of NGC6231 ({Gamma}=-1.1+/-0.1) is slightly shallower than the canonical value, but the difference is marginal. In addition, the mass function varies systematically, and is a strong function of radius-it is very shallow at the center, and very steep at the outer ring suggesting the cluster is mass segregated. We confirm the mass segregation for the massive stars (m>~8 M_{sun}_) by a minimum spanning tree analysis. Using a Monte Carlo method, we estimate the total mass of NGC6231 to be about 2.6(+/-0.6)*10^3^M_{sun}_. We constrain the age of NGC 6231 by comparison with evolutionary isochrones. The age of the low-mass stars ranges from 1 to 7Myr with a slight peak at 3Myr. However, the age of the high-mass stars depends on the adopted models and is 3.5+/-0.5Myr from the non-rotating or moderately rotating models of Brott et al. (2011, cat. J/A+A/530/A115) as well as the non-rotating models of Ekstrom et al. (2012, cat. J/A+A/537/A146). But the age is 4.0-7.0Myr if the rotating models of Ekstrom et al. (2012, cat. J/A+A/537/A146) are adopted. This latter age is in excellent agreement with the timescale of ejection of the high-mass runaway star HD153919 from NGC6231, albeit the younger age cannot be entirely excluded.
- ID:
- ivo://CDS.VizieR/J/A+A/407/527
- Title:
- UBVIc and JHK photometry of NGC 1582 and NGC 1663
- Short Name:
- J/A+A/407/527
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD UBV(I)c observations obtained in the field of the previously unstudied northern open clusters NGC 1582 and NGC 1663. For the former, we also provide high-resolution spectra of the brightest stars and complement our data with Two-Micron All Sky-Survey (2MASS) near-infrared photometry and with astrometric data from the Tycho-2 catalog. From the analysis of all these data, we argue that NGC 1582 is a very poor, quite large and heavily contaminated open cluster. It turns out to have a reddening E(B-V)=0.35+/-0.03, to be situated 1100+/-100pc from the Sun and to have an age of 300+/-100Myr. On the other hand, we were not able to unambiguously clarify the nature of NGC 1663. By assuming it is a real cluster and from the analysis of its photometric diagrams, we found a color excess value E(B-V)=0.20, an intermediate age value (~2000Myr) and a distance of about 700pc. The distribution of the stars in the region however suggests we are probably facing an open cluster remnant. As an additional result, we obtained aperture photometry of three previously unclassified galaxies placed in the field of NGC 1663 and performed a preliminary morphological classification of them.