相关论文: Multiple Stellar Populations in NGC 2808: a Case S…

Multiple stellar populations (MPs) are a distinct characteristic of Globular Clusters (GCs). Their general properties have been widely studied among main sequence, red giant branch (RGB) and horizontal branch (HB) stars, but a common…

We present Str\"omgren photometry of the Galactic Globular Cluster M3 to study its multiple generations phenomenon. The use of different colour-magnitude diagrams and especially of the notoriously efficient c_y index allowed us to detect a…

Stars in massive star clusters exhibit intrinsic variations in some light elements (MPs) that are difficult to explain in a coherent formation scenario. In recent years, HST photometry has led to the characterisation of the global…

By combining high-resolution (HST-WFPC2) and wide-field ground based (2.2m ESO-WFI) and space (GALEX) observations, we have collected a multi-wavelength photometric data base (ranging from the far UV to the near infrared) of the galactic…

Our understanding of multiple populations in globular clusters (GCs) largely comes from photometry and spectroscopy: appropriate photometric diagrams can disentangle first and second populations (1P and 2P)-1P having chemical signatures…

NGC 4815 is a distant and populous open cluster, which lies in the galactic plane in a region of strong absorption. As a consequence, its membership, spatial distribution and luminosity function are not well determined. In this paper, we…

We have obtained HST-NICMOS observations of five of M31's most metal rich globular clusters. These data allow photometry of individual stars in the clusters and their surrounding fields. However, to achieve our goals -- obtain accurate…

Even after decades of research, the origin of multiple stellar populations in globular clusters remains enigmatic. The question as to whether the galaxy environment plays a role in their formation remains unanswered. To that extent, we…

We used data from the HST UV Legacy Survey of Galactic Globular Clusters to select the Blue Straggler Star (BSS) population in four intermediate/high density systems (namely NGC 2808, NGC 6388, NGC 6541 and NGC 7078) through a "UV-guided…

We present high quality near infrared Color Magnitude Diagrams of 10 Galactic Globular Clusters (GCs) spanning a wide metallicity range (-2.15<[Fe/H]<-0.2). This homogeneous data-base has been used to perform a detailed analysis of the Red…

The presence of multiple populations in globular clusters has been well established thanks to high-resolution spectroscopy. It is widely accepted that distinct populations are a consequence of different stellar generations: intra-cluster…

Using PHANGS-HST NUV-U-B-V-I imaging of 17 nearby spiral galaxies, we study samples of star clusters and stellar associations, visually selected to be bright and relatively isolated, for three purposes: to compute aperture corrections for…

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…

The NASA space telescope Kepler has provided unprecedented time-series observations which have revolutionised the field of asteroseismology, i.e. the use of stellar oscillations to probe the interior of stars. The Kepler-data include…

There is a growing body of evidence for the presence of multiple stellar populations in some globular clusters, including NGC 1851. For most of these peculiar globular clusters, however, the evidence for the multiple red giant-branches…

Photometric investigations have revealed that Galactic globular clusters exhibit internal metallicity variations amongst the so-called first-population stars, until now considered to have a homogeneous initial chemical composition. This is…

We investigate the relationship between the mass of a globular cluster core and the sizes of its various stellar populations in a sample of 56 globular clusters. The number of core red giant branch stars is found to scale sub-linearly with…

We present the results of an all-sky survey made with the Fine Guidance Sensor on Hubble Space Telescope to search for angularly resolved binary systems among the massive stars. The sample of 224 stars is comprised mainly of Galactic O- and…

We use deep images taken with the Advanced Camera for Surveys on board the Hubble Space Telescope of the disk galaxy NGC 891, to search for globular cluster candidates. This galaxy has long been considered to be a close analog in size and…

In order to study the galaxy population of galaxy clusters with photometric data one must be able to accurately discriminate between cluster members and non-members. The redMaPPer cluster finding algorithm treats this problem…