Related papers: Exploring Star Clusters Using Stromgren uvby Photo…
Open clusters are useful tools to investigate the structure and evolution of the Galactic disk. We have started a long-term project to obtain UBVI CCD Photometry of open clusters which were little studied before, using the Doyak 1.8 m…
We investigate the capability of the UBVRIJHK photometric system to quantify star clusters in terms of age, metallicity and color excess by their integrated photometry in the framework of PEGASE single stellar population (SSP) models. The…
We explore the age distribution of the globular cluster (GC) system of the nearby elliptical galaxy NGC 5128 using ultraviolet (UV) photometry from Galaxy Evolution Explorer (GALEX) observations, with UV - optical colors used as the age…
We use evolutionary calculations presented in a recent paper (Cassisi et al. 1998) to predict B,V,I magnitudes for stars in galactic globulars. The effect of the adopted mixing length on stellar magnitudes and colors is discussed, showing…
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…
A study of aperture size effects on star cluster photometry in crowded fields is presented. Tests were performed on a sample of 285 star cluster candidates in the South-West field of the M31 galaxy disk, measured in the Local Group Galaxy…
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…
Multi-color photometry of the stellar populations in five fields in the third Galactic quadrant centred on the clusters NGC 2215, NGC 2354, Haffner 22, Ruprecht 11, and ESO489SC01 is interpreted in terms of a warped and flared Galactic…
Theoretical integrated broad-band colors ranging from far-UV to near-IR have been computed for old stellar systems from our evolutionary population synthesis code. These models take into account, for the first time, the detailed systematic…
Multi-wavelength CCD photometry over 21 years has been used to produce deep color-magnitude diagrams together with light curves for the variables in the Galactic globular cluster NGC 5824. Twenty-one new cluster RR Lyrae stars are…
We report on evidence of the inhomogeneity (multiplicity) of the stellar population in the Galactic globular cluster (GC) NGC 3201, which is irregularly reddened across its face. We carried out a more detailed and careful analysis of our…
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…
Studies during the last decade have revealed that nearly all Globular Clusters (GCs) host multiple populations (MPs) of stars with a distinctive chemical patterns in light elements. No evidence of such MPs has been found so far in…
An increasing amount of spectroscopic and photometric evidence is showing that the stellar populations of globular clusters are not as simple as they have been considered for many years. The presence of at least two different populations of…
Globular Cluster (GC) formation seems to be a widespread mode of star formation in extreme starbursts triggered by strong interactions and mergers of massive gas-rich galaxies. We use our detailed chemically consistent evolutionary…
Star clusters are good tracers for formation and evolution of galaxies. We compared different fitting methods by using spectra (or by combining photometry) to determine the physical parameters. We choose a sample of 17 star clusters in M33,…
We have developed photometric techniques that can be applied to images with highly-variable backgrounds, as well as to slightly-extended objects (object size comparable to or smaller than PSF size). We have shown that ordinary stellar…
(abridged) The old Star Cluster (SC) systems surrounding any sofar investigated galaxy represent a powerful tool for the understanding of the cosmological evolution of their host galaxies. Phases of enhanced cluster formation can be…
We describe the motivations and background of a large survey of nearby stel- lar populations using the Ultraviolet Optical Telescope (UVOT) aboard the Swift Gamma-Ray Burst Mission. UVOT, with its wide field, NUV sensitivity, and 2.3…
We present UBVRI and CT1T2 photometry for fifteen catalogued open clusters of relative high brightness and compact appearance. From these unprecedented photometric data sets, covering wavelengths from the blue up to the near-infrared, we…