Related papers: DDO216-A1: a central globular cluster in a low-lum…
The global properties of all known Galactic globular clusters are examined. The relationship between the luminosities and the metallicities of Galactic globular clusters is found to be complex. Among luminous clusters there is a correlation…
Fifty-seven nearby low surface brightness dwarf galaxies were searched for globular cluster candidates (GCCs) using Hubble Space Telescope WFPC2 imaging in V and I. The sample consists of 18 dwarf spheroidal (dSph), 36 irregular (dIrr), and…
The chemical composition of globular clusters (GCs) across the Local Group provides information on chemical abundance trends. The host galaxy, Sextans A, is a low-surface-brightness dwarf irregular galaxy located on the edge of the Local…
Globular clusters in the Galactic bulge are difficult to study due to high extinction and severe crowding. VVV-CL001 is an old, metal-poor, and fast cluster in the inner bulge, whose extreme properties make it a key probe of the early…
We present low-resolution Keck spectroscopy for the globular cluster H VIII in the Local Group dIrr galaxy NGC 6822. We find the metallicity of the cluster to be [Fe/H]= -1.58 +/- 0.28 and the age of the cluster to be 3-4 Gyr, slightly…
We investigate an infrared-excess source called G2 or Dusty S-cluster Object (DSO) moving on a highly eccentric orbit around the Galaxy's central black hole, Sgr A*. We use, for the first time, near-infrared polarimetric imaging data to…
We use Subaru Suprime-Cam and VLT FORS1 photometry of the dwarf galaxy DDO210 to study the global stellar content and structural properties of a transition-type galaxy (with properties intermediate between dwarf irregular and dwarf…
We have studied Leo A - the isolated and extremely gas rich dwarf irregular galaxy of very low stellar mass and metallicity. Ages of the stellar populations in Leo A are ranging from ~10 Myr to ~10 Gyr. Here we report the discovery of an…
We present new H-alpha narrow band imaging of the HII regions in eight Sculptor Group dwarf irregular (dI) galaxies. Comparing the Sculptor Group dIs to the Local Group dIs, we find that the Sculptor Group dIs have, on average, lower values…
We present V and I CCD photometry of suspected low-surface brightness dwarf galaxies detected in a survey covering ~2.4 deg^2 around the central region of the Dorado group of galaxies. The low-surface brightness galaxies were chosen based…
We present deep optical and near-infrared imaging of the rich cluster A2218 at z=0.17. Our optical imaging comes from new multicolour Hubble Space Telescope WFPC2 observations in the F450W (B), F606W (V) and F814W (I) passbands. These…
We present an HI and optical study of the gas-rich dwarf irregular galaxy DDO 88. Although DDO 88's global optical and HI parameters are normal for its morphological type, it hosts a large (3 kpc diameter) and unusually complete ring of…
A new population of extended, luminous globular clusters has recently been discovered in the outskirts of M31. These objects have luminosities typical of classical globular clusters, but much larger half-light radii. We report the first…
We have observed the center of the Local Group dwarf irregular galaxy IC 1613 with WFPC2 aboard the Hubble Space Telescope in the F439W, F555W, and F814W filters. We find a dominant old stellar population (aged ~7 Gyr), identifiable by the…
DDO68 (UGC5340) is an unusual dwarf galaxy with extremely low gas metallicity (12+log(O/H) = 7.14) residing in the nearby Lynx-Cancer void. Despite its apparent isolation, it shows both optical and HI morphological evidence for strong tidal…
The globular cluster HP1 is projected on the bulge, very close to the Galactic center. The Multi-Conjugate Adaptive Optics (MCAO) Demonstrator (MAD) at the Very Large Telescope (VLT) allowed to acquire high resolution deep images that,…
We have obtained V and I images of the lone globular cluster that belongs to the dwarf Local Group irregular galaxy known as WLM. The color-magnitude diagram of the cluster shows that it is a normal old globular cluster with a well-defined…
We present the results of a Hubble Space Telescope (HST) ACS and WFPC2 study of dwarf galaxies in the nearby Perseus Cluster, down to M_V = -12, spanning the core and outer regions of this cluster. We examine how properties such as the…
At ~50 Mpc, the Hydra I cluster of galaxies is among the closest cluster in the z=0 Universe, and an ideal environment to study dwarf galaxy properties in a cluster environment. We exploit deep imaging data of the Hydra I cluster to…
We present a comprehensive analysis of the globular cluster (GC) system of the Local Group dwarf irregular galaxy NGC 6822. Our study is based on homogeneous optical and near-IR photometry, as well as long-slit spectroscopic observations…