相关论文: UBVI CCD Photometry of the Old Open Cluster Berkel…

We have obtained BVI CCD imaging of Berkeley 17, an anticentre open cluster that competes with NGC 6791 as the oldest known open cluster. Using the synthetic colour magnitude diagrams (CMD) technique with three sets of evolutionary tracks…

We report on near IR ($J$ and $K$ bands) observations of two $8 \times 8 \~(arcmin)^{2}$ regions centered on the old open clusters Berkeley~17 and Berkeley~18, for which only optical photometry (in $B$,$V$ and $I$ bands) exists. $J$ and $K$…

CCD BVI photometry of the faint open clusters Berkeley~73, Berkeley~75 and Berkeley~25 are presented. The two latter are previously unstudied clusters to our knowledge. While Berkeley~73 is found to be of intermediate-age (about 1.5 Gyr…

We present the analysis of the morphological shape of Berkeley 17, the oldest known open cluster (~10 Gyr), using a probabilistic star counting of Pan-STARRS point sources, and confirm its core-tail shape, plus an antitail, previously…

We present CCD BVI photometry of the old open cluster Berkeley 21, one of the most distant clusters in the Galactic anticentre direction, and possibly the lowest metallicity object in the open clusters sample. Its position and metal…

Aim of this study is to infer the age of the Galactic Disk by means of the ages of old open clusters, and comment on some recent claims that the Galactic Disk can be older than the Halo. To this purpose, we analyze the Color-Magnitude…

New photometric material is presented for 6 outer disk supposedly old, Galact ic star clusters: Berkeley 76, Haffner 4, Ruprecht 10, Haffner 7, Haffner 11, and Haffner 15, that are projected against the rich and complex Canis Major overde…

We present CCD BVI photometry of the old open cluster Berkeley 29, located in the anticentre direction. Using the synthetic Colour - Magnitude Diagrams technique we estimate at the same time its age, reddening, distance, and approximate…

In this paper we present the investigation of the evolutionary status of three open clusters: Berkeley 27, Berkeley 34, and Berkeley 36, all located in the Galactic anti-centre direction. All of them were observed with SUSI2@NTT using the…

We have obtained CCD UBVI_{KC} photometry down to V ~ 21.0 for the open clusters Berkeley 26, Czernik 27, Melotte 72, NGC 2479 and BH 37. The latter has never been studied before. Cluster stellar density profiles were obtained from star…

We present BVI CCD photometry of 10 northern open clusters, Berkeley 43, Berkeley 45, Berkeley 47, NGC 6846, Berkeley 49, Berkeley 51, Berkeley 89, Berkeley 91, Tombaugh 4 and Berkeley 9, and estimate their fundamental parameters. Eight of…

In this paper we present the first $BVI$ CCD photometry of six overlooked old open clusters (Berkeley 44, NGC 6827, Berkeley 52, Berkeley 56, Skiff 1 and Berkeley 5) and derive estimates of their fundamental parameters by using isochrones…

We continue our series of papers describing the results of a photometric survey of open star clusters, primarily in the southern hemisphere, taken in the u'g'r'i'z' filter system. The entire observed sample covered more than 100 clusters,…

We report a detailed investigation of three intermediate-to-old age open clusters, Berkeley 17, Berkeley 18, and Berkeley 39, utilizing precise astrometric and photometric data from Gaia DR3. Cluster membership was robustly determined…

In this paper we analyse the evolutionary status of three open clusters: NGC 1817, NGC 2141, and Berkeley 81. They are all of intermediate age, two are located in the Galactic anti-centre direction while the third one is located in the…

To study the crucial range of Galactocentric distances between 12 and 16 kpc, 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…

The heavily obscured open cluster Berkeley~51 shows characteristics typical of young massive clusters, even though the few previous studies have suggested older ages. We combine optical ($UBV$) and 2MASS photometry of the cluster field with…

We observed the Galactic open cluster Berkeley 50 in order to determine its stellar content, distance, and age. We obtained UBV photometry of 1145 stars in a 12.3' $\times$ 12.3' field, and used Gaia proper motions and parallaxes to…

The CCD UBV(RI)KC photometry of the poorly studied open clusters Juchert 9 (Juc 9) and Berkeley 97 (Be 97), which are observed with the 0.84 m telescope at the San Pedro M\'artir National Observatory, M\'exico has been analysed. For the…

We present deep CCD BVI photometry of the distant, old open cluster Berkeley 22, covering from the red giants branch (RGB) to about 6 magnitudes below the main sequence (MS) turn-off. Using the synthetic Colour - Magnitude Diagram method…