Related papers: Pal 1: Another Young Galactic Halo Globular Cluste…
We review the history of the discovery of field subgiant stars and their importance in the age dating of the Galactic disk. We use the cataloged data from the Hipparcos satellite in this latter capacity. Based on Hipparcos parallaxes…
Estimating the age of the Universe is an old problem. Rapid progress in observational cosmology in recent years has led to more accurate values of the fundamental parameters. The current most popular model is a flat Universe, with about 30%…
We report on deep imaging of a remote M31 globular cluster, MGC1, obtained with Gemini/GMOS. Our colour-magnitude diagram for this object extends ~5 magnitudes below the tip of the red giant branch and exhibits features consistent with an…
The Galactic globular cluster system is incomplete, especially in the low latitude regions of the Galactic bulge and disk. We report the physical characterization of twelve star clusters in the Milky Way, most of which are explored here for…
Palomar 5 (Pal 5) is a faint halo globular cluster associated with narrow tidal tails. It is a useful system to understand the process of tidal dissolution, as well as to constrain the potential of the Milky Way. A well-determined orbit for…
Shells in Elliptical Galaxies are faint, sharp-edged features, believed to provide evidence of a recent ($\sim 0.5 - 2 \times 10^9$ years ago) merger event. We analyse the Globular Cluster (GC) systems of six shell elliptical galaxies, to…
We present the first photometric results in J, H, and K_s from 2MASS imaging of 10 classical globular clusters in the far outer regions of M31. Combined with the V and I photometric data from previous literature, we constructed the…
Deep CCD photometry down to V=24.5 is presented for the old Magellanic Globular cluster NGC 2257. The main result cna be summarized as follows: i) the RGB Bump has been detected at V=18.7+-0.1, and is compatible with determination of this…
We present the first part of the first large and homogeneous CCD color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I bands using only two telescopes (one for each hemisphere).…
PHR 1315-6555 is a rare case of a Galactic Planetary Nebula that is a proven member of the Open Cluster AL 1. This allows its distance to be defined with precision and thus the accurate measurement of its physical characteristics along with…
We present preliminary results from our on-going survey of Galactic globular clusters relative ages. The investigation is based on V,I images obtained at the ESO and La Palma telescopes, which make up the largest homogenous photometric…
Star formation in starbursts appears to be biased toward compact clusters, with up to 20% of all stars formed in them. Observations with HST show that many of these clusters have luminosities (-9 > Mv > -16), UBVI colors, and half-light…
The study of outer halo globular cluster (GC) populations can give insight into galaxy merging, globular cluster accretion and the origin of GCs. We use archival Subaru Hyper Suprime-Cam (HSC) data in concert with space-based GALEX, IRAC…
We report the confirmation of an old, metal-poor globular cluster in the nearby dwarf irregular galaxy Sextans A, the first globular cluster known in this galaxy. The cluster, which we designate as Sextans A-GC1, lies some 4.4 arcminutes…
We report on the discovery of an extended stellar halo surrounding the distant Galactic globular cluster NGC 5694, based on new deep (V ~ 24.5) wide-field (24' * 20') photometry acquired with VIMOS at VLT. Stars with colour and magnitude…
We use deep multi-epoch PSF photometry taken with the Visible and Infrared Survey Telescope for Astronomy (VISTA) to measure and analyze the proper motions of stars within the Galactic globular cluster 47 Tucanae (47 Tuc, NGC 104). The…
Low-resolution UV-to-visual spectra of two candidate globular clusters in the merger remnant NGC 3921 are presented. These two clusters of apparent magnitude V = 22.2 (Mv = -12.5) lie at projected distances of ~5 kpc from the center and…
We present extensive UBVR photometry of the Galactic globular cluster (GGC) NGC6712 obtained with the ESO Very Large Telescope (VLT) which reach down to two magnitudes below the main sequence turn-off and allows us for the first time to…
We present the stellar population, using {\it Gaia}\,DR2 parallax, kinematics, and photometry, of the young ($\sim 100$~Myr), nearby ($\sim 230$~pc) open cluster, Blanco1. A total of 644 member candidates are identified via the unsupervised…
We present the first results of a large spectroscopic survey of candidate globular clusters located in the extreme outskirts of the nearby M31 galaxy. We obtained low resolution spectra of 48 targets selected from the XSC of 2MASS, as in…