Related papers: Structural parameters and blue stragglers in Sagit…
We present an analysis of the density profile in the central region of the Sagittarius dwarf spheroidal galaxy. A strong density enhancement of Sgr stars is observed. The position of the peak of the detected cusp is indistinguishable from…
We use the astrometric and photometric data from Gaia Data Release 2 and line-of-sight velocities from various other surveys to study the 3d structure and kinematics of the Sagittarius dwarf galaxy. The combination of photometric and…
We investigate the hierarchical distribution and evolution of young stellar structures in the dwarf starburst galaxy NGC 4449 using data from the GULP survey. By analyzing the spatial distribution of field stars younger than 100 Myr, we…
We used high resolution spectra acquired at the Magellan Telescope to measure radial and rotational velocities of approximately 200 stars in the Galactic globular cluster NGC 3201. The surveyed sample includes Blue Stragglers Stars (BSSs)…
Deep images in the 10 micron spectral region have been obtained for five massive Galactic globular clusters, NGC 104 (=47 Tuc), NGC 362, NGC 5139 (omega Cen), NGC 6388, NGC 7078 (=M15) and NGC 6715 (=M54) in the Sagittarius Dwarf Spheroidal…
We use a combination of data acquired with the Advanced Camera for Survey (ACS) on board the Hubble Space Telescope and the Large Binocular Camera (LBC-blue) mounted on the Large Binocular Telescope, to sample the main sequence stars of the…
Recently, new Sagittarius (Sgr) dwarf galaxy globular clusters were discovered, which opens the question on the actual size of the Sgr globular cluster population, and therefore on our understanding of the Sgr galaxy formation and accretion…
Previous studies have found that ~1 deg2 fields surrounding the stellar aggregates in the Taurus star-forming region exhibit a surplus of solar-mass stars relative to denser clusters like IC~348 and the Orion Nebula Cluster. To test whether…
We have analyzed ACS/WFC and WFPC2 images from HST, as well as ground-based data to study the radial distribution of the double sub-giant branch (SGB) recently discovered in the Galactic globular cluster NGC 1851. We found that the SGB…
Recent high-resolution observations of the central region of Galactic globular clusters have shown the presence of a large variety of exotic stellar objects whose formation and evolution may be strongly affected by dynamical interactions.…
We report the results of a systematic photometric survey of the peripheral regions of a sample of fourteen globular clusters in the outer halo of the Milky Way at distances d_GC>25 kpc from the Galactic centre. The survey is aimed at…
We have used a combination of high-resolution Hubble Space Telescope WFPC2 and wide-field ground-based observations in ultraviolet and optical bands to study the blue straggler star (BSS) population of the outer-halo globular cluster NGC…
The relative average minimum projected separations of star clusters in the Legacy ExtraGalactic UV Survey (LEGUS) and in tidal dwarfs around the interacting galaxy NGC 5291 are determined as a function of cluster mass to look for…
We summarize the results of our ongoing investigation of the chemical abundances in the Sagittarius Dwarf Spheroidal Galaxy (Sgr dSph) and in the Canis Major Overdensity (CMa). 12 RGB stars were analyzed in the Sgr dSph, plus 5 in the…
We used high-quality images acquired with the WFC3 on board the HST to probe the blue straggler star (BSS) population of the Galactic globular cluster NGC 362. We have found two distinct sequences of BSS: this is the second case, after M…
We carried out a wide-field V, I imaging survey of the Local Group dwarf spheroidal galaxy Leo II using the Subaru Prime Focus Camera on the 8.2-m Subaru Telescope. The survey covered an area of 26.67 x 26.67 arcmin^2, far beyond the tidal…
We present an analytic model for blue straggler formation in globular clusters. We assume that blue stragglers are formed only through stellar collisions and binary star evolution, and compare our predictions to observed blue straggler…
We present results from a wide-field imaging study of the globular cluster (GC) systems of a sample of edge-on, Sb-Sc spiral galaxies ~7-20 Mpc away. This study is part of a larger survey of the ensemble properties of the GC populations of…
We present the results of a search for variability in and near the core of the metal-rich, obscured globular cluster Terzan 5, using NICMOS on HST. This extreme cluster has approximately solar metallicity and a central density that places…
We isolate samples of 733 bright (g < 18) and 437 faint (g > 18) high-Galactic latitude blue horizontal branch stars with photometry and spectroscopy in the Sloan Digital Sky Survey (SDSS). Comparison of independent photometric and…