相关论文: Open Clusters in the Kepler Field, II. NGC 6866
Aims. We are searching for new open clusters or moving groups in the Solar neighbourhood. Methods. We used the Gaia-TGAS catalogue, cut it into narrow proper motion and parallax slices and searched for significant spatial over-densities of…
NGC 663 is a young, moderately rich open cluster, known to contain one of the largest fractions of Be stars among all galactic clusters. In this work we present CCD uvby-beta photometry for stars in its central area. We have used these data…
The detection of magnetic chemically peculiar (CP2) stars in open clusters of the Milky Way can be used to study the influence of different galactic environments on the (non-)presence of peculiarities, which has to be taken into account in…
With an apparent cluster diameter of 1.5{\deg} and an age of ~4 Myr, Trumpler 37 is an ideal target for photometric monitoring of young stars as well as for the search of planetary transits, eclipsing binaries and other sources of…
We present the results of a deep, wide-field CCD survey for the open cluster NGC~3532. Our new $BV(RI)_{c}$ photometry effectively covers a one square degree area and reaches an unprecedented depth of $V\sim21$ to reveal that NGC~3532 is a…
The color-magnitude diagrams of the open clusters NGC 2420 and NGC 2506 have been investigated as intermediate links between the solar neighborhood and the Magellanic Clouds. Two sets of theoretical isochrones which include convective…
CCD photometry on the intermediate-band uvbyCaH-beta system is presented for the old open cluster, NGC 6253. Despite a high level of field star contamination due to its location toward the galactic center, combination of the data from the…
Fundamental astrophysical parameters have been derived for 20 open clusters (O\!Cs) using CCD~$U\!BV\!(RI)_C$ photometric data observed with the 84~cm telescope at the San Pedro M\'artir National Astronomical Observatory, M\'exico. The…
We use photometric and spectroscopic observations of the detached eclipsing binaries V40 and V41 in the globular cluster NGC 6362 to derive masses, radii, and luminosities of the component stars. The orbital periods of these systems are…
Accurate stellar parameters of stars in open clusters can help constrain models of stellar structure and evolution. Here we wish to determine the age and metallicity content of the open cluster NGC 2506. To this end we investigated three…
We report the results of a detailed numerical study designed to estimate both the absolute age and the uncertainty in age (with confidence limits) of the oldest globular clusters. Such an estimate is essential if a comparison with the…
We have investigated the two open clusters NGC 6192 and NGC 6451 for which widely different reddening values and thus ages and distances can be found in the literature via Stroemgren uvby photometry. Our measurements allow to disentangle…
We present and discuss new photometric data obtained with an IR camera in the J and K pass-bands for the intermediate age open clusters IC 166 (936 stars in total) and NGC 7789 (1030 stars in total). Ic 166 is a poorly studied open cluster…
Open clusters belonging to star-forming complexes are the leftovers from the initial stellar generations. The study of these young systems provides constraints to models of star formation and evolution as well as to the properties of the…
We use the Main Sequence stars in the LMC cluster NGC 1866 and of Red Clump stars in the local field to obtain two independent estimates of the LMC distance. We apply an empirical Main Sequence-fitting technique based on a large sample of…
The Kepler space telescope has proven to be a gold mine for the study of variable stars. Unfortunately, Kepler only returns a handful of pixels surrounding each star on the target list, which omits a large number of stars in the Kepler…
We present CCD UBVI observations obtained in the field of the two previously unstudied dissolving open cluster candidates NGC 7036 and NGC 7772. Our analysis suggests that both the objects are Open Cluster Remnants (OCR). NGC 7036 is an…
We present results of age determination based on the standard procedure of isochrone fitting for about 600 star clusters younger than about 1.2 Gyr from the central parts of the LMC. Comparison of age distributions of star clusters from the…
We present a maximum likelihood method for fitting two-dimensional model distributions to stellar data in colour-magnitude space. This allows one to include (for example) binary stars in an isochronal population. The method also allows one…
Relative proper motions and cluster membership probabilities have been derived for ~ 2500 stars in the field of the open star cluster NGC 3766. The cluster has been observed in $B$ and $V$ broadband filters at two epochs separated by ~ 6…