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- ID:
- ivo://CDS.VizieR/J/A+A/375/863
- Title:
- Photometry in NGC 2516
- Short Name:
- J/A+A/375/863
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a 0.86 square degree CCD photometric survey of the open cluster NGC 2516, which has an age of about 150Myr and may have a much lower metallicity than the similarly-aged Pleiades. Our BVI_c_ survey of cluster members is complete to V~20 and is used to select a preliminary catalogue of 1254 low mass (0.<M<2.0M_{sun}_) cluster candidates, of which about 70-80 percent are expected to be genuine. After applying corrections for contamination by non-members and adding data for higher mass stars from the literature, we investigate the cluster binarity, luminosity and mass function, mass segregation and total mass. We find a binary fraction of 26+/-5%, for A to M-type systems with mass ratios between 0.6 and 1, which is very similar to the Pleiades.
- ID:
- ivo://CDS.VizieR/J/PASP/105/78
- Title:
- Photometry in open cluster NGC 5822
- Short Name:
- J/PASP/105/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study presents photoelectric photometry of stars in NGC 5822 on the UBVR and DDO systems. The BV data are employed to calibrate a photographic survey of the cluster, while UBV and DDO data are used to constrain the cluster reddening and metallicity. Taken in conjunction with previous photometric analysis, it is found that the cluster has a reddening of 0.15+/-0.015(pe) as defined for the stars at the turnoff, and a metallicity relative to the sun of -0.15+/-0.05(pe).
- ID:
- ivo://CDS.VizieR/J/AJ/156/37
- Title:
- Photometry & Li abund. of cool dwarfs in M35
- Short Name:
- J/AJ/156/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hydra spectra of 85 G-K dwarfs in the young cluster M35 near the Li 6708 {AA} line region are analyzed. From velocities and Gaia astrometry, 78 are likely single-star members that, combined with previous work, produce 108 members with T_eff_ ranging from 6150 to 4000 K as defined by multicolor, broadband photometry, E(B-V)=0.20, and [Fe/H]=-0.15, though there are indications the metallicity may be closer to solar. The Lithium abundance A(Li) follows a well-delineated decline from 3.15 for the hottest stars to upper limits =<1.0 among the coolest dwarfs. Contrary to earlier work, M35 includes single stars at systematically higher A(Li) than the mean cluster relation. This subset exhibits higher V_ROT_ than the more Li-depleted sample and, from photometric rotation periods, is dominated by stars classed as convective (C); all others are interface (I) stars. The cool, high-Li rapid rotators (RRs) are consistent with models that simultaneously consider rapid rotation and radius inflation; RRs hotter than the Sun exhibit excess Li depletion, as predicted by the models. The A(Li) distribution with color and rotation period, when compared to the Hyades/Praesepe and the Pleiades, is consistent with gyrochronological analysis placing M35's age between the older M34 and younger Pleiades. However, the Pleiades display a more excessive range in A(Li) and rotation period than M35 on the low-Li, slow-rotation side of the distribution, with supposedly younger stars at a given T_eff_ in the Pleiades spinning slower, with A(Li) reduced by more than a factor of four compared to M35.
- ID:
- ivo://CDS.VizieR/J/A+A/483/209
- Title:
- Photometry of a stellar cluster near IRAS 07141-092
- Short Name:
- J/A+A/483/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution optical UBVRI and H{alpha} images obtained with ALFOSC mounted on the Nordic Optical Telescope (NOT), near-infrared JHK_S_ images obtained with NOTCam at the Nordic Optical Telescope, and VLT/ISAAC images obtained through the H_2_ (2.12{mu}m) filter were all used to make photometric and morphological studies of the point sources and the nebula seen towards Sh2-294. Identification of PMS members was done using three different methods: comparison with isochrones in optical colour-magnitude diagrams and detection of either near-IR excess or H{alpha} emission.
- ID:
- ivo://CDS.VizieR/J/A+A/496/453
- Title:
- Photometry of candidate members of NGC6611
- Short Name:
- J/A+A/496/453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the list of candidate members of the young open cluster NGC 6611, selected in a field of view of 33'x34' by the X-rays emission and excesses in infrared bands. X-ray sources without infrared excesses are classified as candidate Class III cluster members; stars with infrared excesses as disk bearing members.
- ID:
- ivo://CDS.VizieR/J/A+A/588/A63
- Title:
- Photometry of DBS 77-78-102-160-161 regions
- Short Name:
- J/A+A/588/A63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a study of the global properties of some embedded clusters placed in the fourth quadrant of the MilkyWay to clarify some issues related with their location into de Galaxy and their stellar formation processes. We performed BVI photometric observations in the region of DBS 77, 78, 102, 160, and 161 clusters and infrared spectroscopy in DBS 77 region. They were complemented with JHK data from VVV survey combined with 2MASS catalogue, and used mid-infrared information from GLIMPSE catalogue. We also searched for HI data from SGPS and PMN radio surveys, and previous spectroscopic stellar classification. The spectroscopic and photometric information allowed us to estimate the spectral classification of the brightest stars of each studied region. On the other hand, we used the radio data to investigate the interstellar material parameters and the continuum sources probably associated with the respective stellar components. We estimated the basic physical parameters of the clusters (reddening, distance, age, and initial mass function). We searched for HII regions located near to the studied clusters and we analyzed the possible link between them. In the particular case of DBS 160-161 clusters, we identified the HI bubble B332.5-0.1-42 located around them. We found that the mechanical energy injected to the interstellar medium by the more massive stars of this couple of clusters was enough to generate the bubble.
- ID:
- ivo://CDS.VizieR/J/MNRAS/416/1077
- Title:
- Photometry of 3 open clusters
- Short Name:
- J/MNRAS/416/1077
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A comprehensive census of Galactic open cluster properties places unique constraints on the Galactic disc structure and evolution. In this framework, we investigate the evolutionary status of three poorly studied open clusters, Berkeley 31, Berkeley 23 and King 8, all located in the Galactic anticentre direction. To this aim, we make use of deep Large Binocular Telescope observations, reaching more than 6mag below the main-sequence turn-off. To determine the cluster parameters, namely age, metallicity, distance, reddening and binary fraction, we compare the observational colour--magnitude diagrams (CMDs) with a library of synthetic CMDs generated with different evolutionary sets (Padova, FRANEC and FST) and metallicities. We find that Berkeley 31 is relatively old, with an age between 2.3 and 2.9Gyr, and rather high above the Galactic plane, at about 700pc. Berkeley 23 and King 8 are younger, with best-fitting ages in the range 1.1-1.3 and 0.8-1.3 Gyr, respectively. The position above the Galactic plane is about 500-600 pc for the former and 200 pc for the latter. Although a spectroscopic confirmation is needed, our analysis suggests a subsolar metallicity for all three clusters. Based on observations collected at the Large Binocular Telescope (LBT) and in part at the Italian Telescopio Nazionale Galileo (TNG). The LBT is an international collaboration among institutions in the United States, Italy and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona University system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota and University of Virginia. The TNG is operated on the island of La Palma by the Fundacion Galileo Galilei of the INAF (Istituto Nazionale di Astrofisica) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.
- ID:
- ivo://CDS.VizieR/J/MNRAS/412/1265
- Title:
- Photometry of 3 open clusters
- Short Name:
- J/MNRAS/412/1265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To study the crucial range of Galactocentric distances between 12 and 16kpc, where little information is available, we have obtained VI CCD imaging of Berkeley 20 and BVI CCD imaging of Berkeley 66 and Tombaugh 2, three distant, old open clusters. Using the synthetic colour magnitude diagram (CMD) technique with three types of evolutionary tracks of different metallicities, we have determined age, distance, reddening and indicative metallicity of these systems. The CMD of Be 20 is best reproduced by stellar models with a metallicity about half of solar (Z=0.008 or 0.01), in perfect agreement with high resolution spectroscopic estimates. Its age is between 5 and 6Gyr from stellar models with overshooting and between 4.3 and 4.5Gyr from models without it. The distance modulus from the best fitting models is always (m-M)=14.7 (corresponding to a Galactocentric radius of about 16kpc), and the reddening E(B-V) ranges between 0.13 and 0.16. A slightly lower metallicity (Z=~0.006) appears to be more appropriate for Be 66. This cluster is younger (3Gyr), and closer, (m-M)=13.3 (i.e., at 12kpc from the Galactic centre), than Be 20, and suffers from high extinction, 1.2<=E(B-V)<=1.3, variable at the 2-3% level. Finally, the results for To 2 indicate that it is an intermediate age cluster, about 1.4Gyr or 1.6-1.8Gyr for models without and with overshooting, respectively. The metallicity is about half of solar (Z=0.006 to 0.01), in agreement with spectroscopic determinations. The distance modulus is (m-M)=14.5, implying a distance of about 14kpc from the Galactic centre; the reddening E(B-V) is 0.31-0.4, depending on the model and metallicity, with a preferred value around 0.34.
- ID:
- ivo://CDS.VizieR/J/A+A/473/149
- Title:
- Photometry of sources in IRAS 16362-4845 cluster
- Short Name:
- J/A+A/473/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The IRAS 16362-4845 star-forming site in the RCW 108 complex contains an embedded compact cluster that includes some massive O-type stars. Star formation in the complex, and in particular in IRAS 16362-4845, has been proposed to be externally triggered by the action of NGC 6193. We present a photometric study of the IRAS 16362-4845 cluster sensitive enough to probe the massive brown dwarf regime. In particular, we try to verify an apparent scarcity of solar-type and low-mass stars reported in a previous paper (Comeron et al., 2005A&A...433..955C).
