Related papers: A low surface brightness halo surrounding the glob…
We present a new catalog of 81 ancient globular clusters (GCs) in the early-type spiral (SB0/a) galaxy NGC 1291. Candidates have been selected from B,V, and I band images taken with the Hubble Space Telescope, which also reveal 17 younger…
We examine the outer structure of 12 Galactic globular clusters using star-count analyses. Deep, two-color, photographic photometry is used to select and count stars with colors and magnitudes consistent with cluster-specific,…
We investigate the shallow increase in globular cluster half-light radii with projected galactocentric distance $R_{gc}$ observed in the giant galaxies M87, NGC 1399, and NGC 5128. To model the trend in each galaxy, we explore the effects…
I-band CCD images of a large area of the nearby globular cluster NGC~6397 have been used to construct a surface density profile and two luminosity and mass functions. The surface density profile extends out to 14\arcm from the cluster…
In a new HI imaging survey of Virgo galaxies (VIVA: VLA Imaging of Virgo galaxies in Atomic gas), we find 7 spiral galaxies with long HI tails. The morphology varies but all the tails are extended well beyond the optical radii on one side.…
We present VLT (FORS1) photometry of the lower main sequence (MS) of the Galactic Globular Cluster (GGC) NGC 6397, for stars located in 2 fields extending from a region near the cluster center out to ~ 10'. The obtained CMD shows a narrow…
We report the detection of vertically extended far-ultraviolet (FUV) and near-UV emissions in an edge-on spiral galaxy NGC 891, which we interpret as being due to dust-scattered starlight. Three-dimensional radiative transfer models are…
We report the discovery in our HST ACS B, V, and I images of NGC 4449 of a globular cluster (GC) which appears associated with two tails of blue stars. The cluster is massive (M~1.7x10^6 M_sun) and highly flattened (\epsilon~0.24). From the…
This is the second of two papers presenting a detailed examination of Fokker-Planck models for the globular cluster NGC 6397 and is concerned with extracting information on the cluster from the models. The models give a current cluster mass…
Hot gaseous halos are predicted around all large galaxies and are critically important for our understanding of galaxy formation, but they have never been detected at distances beyond a few kpc around a spiral galaxy. We used the Chandra…
In this paper we present multiband optical and UV Hubble Space Telescope photometry of the two Galactic globular clusters NGC 6388 and NGC 6441. We have obtained the first UV color-magnitude diagrams for NGC 6388 and NGC 6441. These…
We present the serendipitous discovery of 195 extragalactic globular clusters (GCs) in one of the deepest optical images ever obtained, a 126 orbit HST/ACS imaging study of the nearby Galactic GC NGC 6397. The distant GCs are all found…
We have obtained deep photometry of NGC 1199 (in HCG 22) and NGC 6868 (in the Telescopium group). Both galaxies are the optically brightest galaxies of their groups. Our analysis of B and R images taken with the Keck II and the VLT/ESO…
In this study, we present a detailed study of mass segregation in the globular clister NGC 6397. First, we carry out a photometric analysis of projected ESO-VLT data (between 1 and 10 arcmin from the cluster centre), presenting the…
Hubble Space Telescope allows us to study the central surface brightness profiles for globular clusters at unprecedented detail. We have mined the HST archives to obtain 38 WFPC2 images of galactic globular clusters with adequate exposure…
The surroundings of globular clusters in the outer halo are one of the best places to look for the remnants of ancient dwarf satellites. The classical Searle & Zinn (1978) scenario of the formation of the Milky Way, in which the halo…
We present the first evidence of clear signatures of tidal distortions in the density distribution of the fascinating open cluster NGC 6791. We used deep and wide-field data obtained with the Canada-France-Hawaii-Telescope covering a 2x2…
We present H-band images obtained with NICMOS of a field 75'' (5kpc) above the plane of the disk of the edge-on spiral galaxy NGC 5907. Ground-based observations have shown that NGC 5907 has a luminous halo with a shallow radial profile…
We present the results of a wide-field imaging survey of the periphery of the Milky Way globular cluster NGC 7089 (M2). Data were obtained with MegaCam on the Magellan Clay Telescope, and the Dark Energy Camera on the Blanco Telescope. We…
We searched the Sloan Digital Sky Survey for outer halo globular clusters (GCs) around M31. Our search of non-stellar objects, within the limits 0.3 < (g-i)o < 1.5 and 14.0 < ro < 19.0 concentrated in some remote areas of the extended halo,…