- ID:
- ivo://CDS.VizieR/J/MNRAS/367/1441
- Title:
- UBV(RI)cJHK photometry of NGC 2401
- Short Name:
- J/MNRAS/367/1441
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on a deep optical CCD (UBV(RI)_C) photometric survey and on the Two-Micron All-Sky-Survey (2MASS, <II/246>) data we derived the main parameters of the open cluster NGC 2401. We found this cluster is placed at 6.3+/-0.5kpc (Vo-Mv=14.0+/-0.2) from the Sun and is 25Myr old, what allows us to identify NGC 2401 as a member of the young population belonging to the innermost side of the extension of the Norma-Cygnus spiral-arm in the Third Galactic Quadrant. A spectroscopic study of the emission star LSS 440 that lies in the cluster area revealed it is a B0Ve star; however, we could not confirm it is a cluster member. We also constructed the cluster luminosity function (LF) down to V~22 and the cluster initial mass function (IMF) for all stars with masses above M~1-2M_{sun}_. It was found that the slope of the cluster IMF is x~1.8+/-0.2. The presence of a probable PMS star population associated to the cluster is weakly revealed.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/337/133
- Title:
- UBV(RI)c photometry in clusters Tr 1 and Be 11
- Short Name:
- J/MNRAS/337/133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep UBV(RI)C charge-coupled device (CCD) photometry for the young open star clusters Tr 1 and Be 11. The CCD data for Be 11 are obtained for the first time. The sample consists of ~1500 stars reaching down to V~21mag. Analysis of the radial distribution of the stellar surface density indicates that radius values for Tr 1 and Be 11 are 2.3 and 1.5pc, respectively. The interstellar extinction across the face of the imaged clusters region seems to be non-uniform with a mean value of E(B-V)=0.60+/-0.05 and 0.95+/-0.05mag for Tr 1 and Be 11, respectively. A random positional variation of E(B-V) is present in both the clusters. In the cluster Be 11, the reason for the random positional variation may be the apparent association of the H II region (S 213). The 2MASS JHK data in combination with the optical data in the cluster Be 11 yield E(J-K)=0.40+/-0.20mag and E(V-K)=2.20+/-0.20mag. Colour excess diagrams indicate a normal interstellar extinction law in the direction of the cluster Be 11.
- ID:
- ivo://CDS.VizieR/J/MNRAS/415/1355
- Title:
- UBV(RI)c photometry of NGC 4852
- Short Name:
- J/MNRAS/415/1355
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The southern open cluster NGC 4852 was re-observed in the UBVRI passbands to refine its intrinsic fundamental parameters. An extended spectral coverage was also undertaken aimed at obtaining a clear picture of the kind of stars inhabiting the cluster upper main sequence.
- ID:
- ivo://CDS.VizieR/J/A+A/417/961
- Title:
- UBV(RI)c photometry of NGC 2580 and NGC 2588
- Short Name:
- J/A+A/417/961
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD broad band photometric observations in the fields of the Third Galactic Quadrant open clusters NGC 2580 and NGC 2588 (V(I)c and UBV(RI)c respectively). From the analysis of our data we found that NGC 2580 is located at a distance of about 4kpc and its age is close to 160Myr. As for NGC 2588, it is placed at about 5kpc from the Sun and is 450Myr old. This means that NGC 2588 belongs to the extension of the Perseus arm, whereas NGC 2580 is closer to the local arm structure. The luminosity functions (LFs) have been constructed for both clusters down to V~20 together with their initial mass functions (IMFs) for stars with masses above M~1-1.5M_{sun}_. The IMF slopes for the most massive bins yielded values of x~1.3 for NGC 2580 and x~2 for NGC 2588. In the case of this latter cluster we found evidence of a core-corona structure produced probably by dynamical effect. In the main sequences of both clusters we detected gaps, which we suggest could be real features.
- ID:
- ivo://CDS.VizieR/J/A+A/445/493
- Title:
- UBV(RI)c photometry of NGC 2425 and NGC 2635
- Short Name:
- J/A+A/445/493
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse CCD broad band (UBV(RI)c) photometric data obtained in the fields of the poorly studied open clusters NGC 2425 and NGC 2635. Both clusters are found to be of intermediate age thus increasing the population of open clusters known to be of the age of, or older than, the Hyades. More explicitly, we find that NGC 2425 is a 2.2Gyr old cluster, probably of solar metallicity, located at 3.5kpc from the Sun. NGC 2635 is a Hyades age (600Myr) cluster located at a distance of 4.0kpc from the Sun. Its Colour Magnitude Diagram reveals that it is extremely metal poor for its age and position, thus making it a very interesting object in the context of Galactic Disk chemical evolution models.
- ID:
- ivo://CDS.VizieR/J/MNRAS/429/1102
- Title:
- UBV(RI)c photometry of 6 open clusters
- Short Name:
- J/MNRAS/429/1102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present BVRcIc CCD photometry in the fields of six Galactic open clusters toward the Perseus spiral arm. These data, complemented with J, H and Ks magnitudes from 2MASS, have been used to determine the following ages, distances and colour excesses E(B-V) for these clusters: 40Myr, 3180_-380_^+440^pc, 0.54+/-0.03mag (Berkeley 96); 250Myr, 2410_-200_^+220^pc, 0.77+/-0.06mag (Berkeley 97); 70Myr, 2490_-170_^+180^pc, 0.51+/-0.05mag (King 12); 160Myr, 2830_-150_^+160^pc, 0.88+/-0.09mag (NGC 7261); 280Myr, 2450_-170_^+190^pc, 0.24+/-0.03mag (NGC 7296); 160Myr, 2750_-210_^+220^pc, 0.49+/-0.02mag (NGC 7788). We found gaps in the mass function of clusters Be 97, King 12 and NGC 7788 in the mass intervals [1.3-1.5], [1.4-1.6] and [1.5-1.7] solar masses, respectively.
- ID:
- ivo://CDS.VizieR/J/A+A/453/101
- Title:
- UBV(RI)c photometry of 4 open clusters
- Short Name:
- J/A+A/453/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ages derived from the low mass stars still contracting onto the main sequence often differ from ages derived from the high mass ones that have already evolved away from it. We investigate the general claim of disagreement between these two independent age determinations by representing UBVRI photometry of the young galactic open clusters NGC 2232, NGC 2516, NGC 2547 and NGC 4755, spanning the age range ~10-150Myr.
- ID:
- ivo://CDS.VizieR/J/A+A/430/471
- Title:
- UBV(RI)c photometry of Stock 16
- Short Name:
- J/A+A/430/471
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep CCD UBV(RI)c photometry has been carried out in the area of the open cluster Stock 16. The different photometric diagrams indicate the presence of three superimposed stellar groups, all composed of early type stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/392
- Title:
- UBVRICT1T2 photometry of 7 open clusters
- Short Name:
- J/MNRAS/466/392
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive UBVRI and Washington CT_1_T_2_ photometric analysis of seven catalogued open clusters, namely: Ruprecht 3, 9, 37, 74, 150, ESO 324-15 and 436-2. The multiband photometric data sets in combination with 2MASS photometry and Gaia astrometry for the brighter stars were used to estimate their structural parameters and fundamental astrophysical properties. We found that Ruprecht 3 and ESO 436-2 do not show self-consistent evidence of being physical systems. The remained studied objects are open clusters of intermediate age (9.0<=log(t[yr^-1^])<=9.6), of relatively small size (r_cls_~0.4-1.3pc) and placed between 0.6 and 2.9kpc from the Sun. We analysed the relationships between core, half-mass, tidal and Jacoby radii as well as half-mass relaxation times to conclude that the studied clusters are in an evolved dynamical stage. The total cluster masses obtained by summing those of the observed cluster stars resulted to be ~10-15 per cent of the masses of open clusters of similar age located closer than 2kpc from the Sun. We found that cluster stars occupy volumes as large as those for tidally filled clusters.
- ID:
- ivo://CDS.VizieR/J/A+A/511/A25
- Title:
- UBVRIH{alpha} photometry of NGC6383
- Short Name:
- J/A+A/511/A25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The very young open cluster NGC 6383 centered on the O-star binary HD 159176 is an interesting place for studying the impact of early-type stars with strong radiation fields and powerful winds on the formation processes of low-mass stars. To investigate this process, it is necessary to determine the characteristics (age, presence, or absence of circumstellar material) of the population of low-mass pre-main-sequence (PMS) stars in the cluster. We obtained deep U B V Rc Ic H{alpha} photometric data of the entire cluster as well as medium-resolution optical spectroscopy of a subsample of X-ray selected objects. Our spectroscopic data reveal only very weak H{alpha} emission lines in a few X-ray selected PMS candidates. We photometrically identify a number of H-{alpha} emission candidates but their cluster membership is uncertain. We find that the fainter objects in the field of view have a wide range of extinction (up to A_V_=20), one X-ray selected OB star having A_V_~8. Our investigation uncovers a population of PMS stars in NGC 6383 that are probably coeval with HD 159176. In addition, we detect a population of reddened objects that are probably located at different depths within the natal molecular cloud of the cluster. Finally, we identify a rather complex spatial distribution of H{alpha} emitters, which is probably indicative of a severe contamination by foreground and background stars.
