Related papers: A Triple Main Sequence in the Globular Cluster NGC…
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…
Galactic globular clusters are not simple stellar populations. And nothing is simple in their study, basically because we try to reconstruct chains of events that occurred at redshift z > 2-3 by observing these objects at z=0, after a…
We quantify the intrinsic width of the red giant branches of three massive globular clusters in M31 in a search for metallicity spreads within these objects. We present HST/ACS observations of three massive clusters in M31, G78, G213, and…
The properties of globular clusters in dwarf galaxies are key to understanding the formation of globular cluster systems, and in particular in verifying scenarios in which globular cluster systems of larger galaxies formed (at least partly)…
We investigate the kinematics of a combined sample of 74 globular clusters around NGC 1399. Their high velocity dispersion, increasing with radius, supports their association with the gravitational potential of the galaxy cluster rather…
We have identified 26 new globular cluster candidates in the inner 3 kpc of NGC 5128 (Cen A), the nearest known large galaxy being the probable product of a merger. The clusters are selected on the basis of their structural parameters…
We report chemical abundances obtained by SDSS-III/APOGEE for giant stars in five globular clusters located within 2.2 kpc of the Galactic centre. We detect the presence of multiple stellar populations in four of those clusters (NGC 6553,…
We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival ACS Treasury observations of 30 Galactic Globular Clusters to characterize two distinct stellar populations. A sophisticated Bayesian technique is employed to…
In this contribution, first results of deep VLT photometry (V,I) in the central region of the Hydra I and Centaurus galaxy clusters are presented. In both galaxy clusters, many star clusters have been identified down to the turnover…
In this paper we present preliminary results from our HST project aimed at exploring the connection between the stellar dynamics and stellar evolution in the cores of high-density globular clusters. We illustrate the discovery of horizontal…
Using new Chandra X-ray observations and existing XMM-Newton X-ray and Hubble far ultraviolet observations, we aim to detect and identify the faint X-ray sources belonging to the Galactic globular cluster NGC 2808 in order to understand…
The majority of the inhomogeneities in the chemical composition of Globular Cluster (GC) stars appear due to primordial enrichment. The most studied model today claims that the ejecta of Asymptotic Giant Branch (AGB) stars of high mass…
Using a combination of high-resolution Hubble Space Telescope/WFPC2 observations, we explore the physical properties of the stellar populations in two intermediate-age star clusters in the Large Magellanic Cloud, NGC 1831 and NGC 1868,…
In the past decade, the notion that globular clusters (GCs) are composed of coeval stars with homogeneous initial chemical compositions has been challenged by growing evidence that they host an intricate stellar population mix, likely…
The radial distribution of globular clusters in galaxies is always less peaked to the centre than the halo stars'. Extending previous work to a sample of HST globular cluster systems in ellipticals, we evaluate the number of clusters lost…
We use images acquired with the Hubble Space Telescope Wide Field Camera 3 and new models to probe the Horizontal Branch (HB) population of the We use images acquired with the Hubble Space Telescope Wide Field Camera 3 and new models to…
Spreads in light element abundances among stars (a.k.a. multiple populations) are observed in nearly all globular clusters. One way to map such chemical variations using high-precision photometry is to employ a suitable combination of…
Using ground-based UBVRI+Halpha CCD photometry we have been carrying out a search for young massive star clusters (YMCs) in a sample consisting of 21 nearby spiral galaxies. We find a large variety concerning the richness of the cluster…
NGC 6388 and NGC 6441 are two massive Galactic bulge globular clusters which share many properties, including the presence of an extended horizontal branch (HB), quite unexpected because of their high metal content. In this paper we use…
We study the globular clusters (GCs) in the spiral galaxy NGC~5907 well-known for its spectacular stellar stream -- to better understand its origin. Using wide-field Subaru/Suprime-Cam $gri$ images and deep Keck/DEIMOS multi-object…