相关论文: UBVI CCD Photometry of the Old Open Cluster NGC 11…
We present UBVI CCD photometry of two open clusters NGC 1798 and NGC 2192 which were little studied before. Color-magnitude diagrams of these clusters show several features typical for old open clusters: a well-defined main-sequence, a red…
We present UBVI photometry for the old open cluster Collinder 261. From comparison of the observed colour-magnitude diagrams with simulations based on stellar evolutionary models we derive in a self consistent way reddening, distance, and…
We present UBVRI photometry for the old open cluster NGC 6253. From comparison of the observed colour-magnitude diagrams with simulations based on stellar evolutionary models we derive in a self consistent way reddening, distance, and age…
Three new photometric CCD-based datasets are presented for NGC~6791. They consist of deep UBV photometry (to $V_{lim} =24$, $B_{lim}=24$, $U_{lim} = 23$) of the central parts of the cluster and of selected fields around it, and of…
We present a BVI optical photometric study of the old open cluster Ruprecht 6 using the data obtained with the SMARTS 1.0 m telescope at the CTIO, Chile. Its color-magnitude diagrams show the clear existence of the main-sequence stars, of…
The open clusters NGC 2323 and NGC 2539 have been analysed using CCD UBV(RI)KC photometric data, observed at the San Pedro Martir Observatory. Cluster memberships have been determined with the proper motion and parallax measures 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 present $UBVRI$ photometry of 8702 stars in a $0.5 ^\circ\times0.5 ^\circ$ field in the direction of NGC 7142, taken with the Half Degree Imager (HDI) at the WIYN 0.9-meter telescope, to improve knowledge of this cluster's basic…
We report on $BVI$ CCD photometry of a field centered on the region of the intermediate-age open cluster NGC 2112 down to V=21. Due to the smaller field coverage, we are able to limit the effect of field star contamination which hampered in…
We report on $UBVRI$ CCD photometry of two overlapping fields in the region of the intermediate-age open cluster NGC 2158 down to V=21. By analyzing Colour-Colour (CC) and Colour-Magnitude Diagrams (CMD) we infer a reddening $E_{B-V}=…
NGC 5822 is a richly populated, moderately nearby, intermediate-age open cluster covering an area larger than the full moon on the sky. A CCD survey of the cluster on the UBVI and uvbyCaHbeta systems shows that the cluster is superposed…
We present JHKs near-infrared CCD photometric study for the Galactic open clusters NGC 1641 and NGC 2394. These clusters have never been studied before, and we provide, for the first time, the cluster parameters; reddening, distance,…
We present JHK near-infrared photometric study for the old open cluster (OC) Trumpler 5 (Tr 5), based on the 2MASS data. From the color-magnitude diagrams of Tr 5, we have located the position of the red giant clump (RGC) stars, and used…
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…
We present CCD UBVI photometry of the nearby, intermediate age open cluster NGC 6939. Using the synthetic Colour - Magnitude Diagrams technique we estimate the following parameters: age between 1.3 and 1.0 Gyr (depending on whether or not…
We present a study of the old open cluster Trumpler 5 (Tr 5), based on the CDS archival data. From the color-magnitude diagrams of Tr 5, we have found the positions of main-sequence turn-off (MSTO) and red giant clump (RGC) stars. Using the…
The fundamental parameters of reddening, metallicity, age, and distance are presented for the poorly studied open clusters Be~89, Ru~135, and Be~10, derived from their CCD UBVRI photometry. By fitting the appropriate isochrones to the…
Fundamental astrophysical parameters have been derived for Be 55 open cluster based on UBVI CCD photometric data, observed with the AZT-22 1.5m telescope at Maidanak Astronomical Observatory in Uzbekistan. The mean reddening is obtained as…
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 three open clusters Be 15, Be 80, and NGC 2192 have been observed using CCD UBV(RI)_C photometry at the San Pedro M\'artir Observatory, M\'exico within the framework of our open-cluster survey. The fundamental parameters of interstellar…