Related papers: A 500 Parsec Halo Surrounding the Galactic Globula…
A candidate diffuse stellar substructure was previously reported in the halo of the nearby dwarf starburst galaxy NGC 4449 by Karachentsev et al. We map and analyze this feature using a unique combination of deep integrated-light images…
We present the preliminary detection of a stellar halo in the nearby, edge-on galaxy, NGC 4244. Using data from the Hubble Space Telescope's Advanced Camera for Surveys (HST/ACS), we have examined number counts of red giant branch (RGB)…
We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…
We present Hubble Space Telescope far-UV spectra of 4 QSOs whose sightlines pass through the halo of NGC 1097 at impact parameters of 48 -165 kpc. NGC 1097 is a nearby spiral galaxy that has undergone at least two minor merger events, but…
NGC 5053 provides a rich environment to test our understanding of the complex evolution of globular clusters (GCs). Recent studies have found that this cluster has interesting morphological features beyond the typical spherical distribution…
We discuss the density and radial velocity distributions of over 3000 candidate RR Lyrae stars selected by various methods using Sloan Digital Sky Survey data for about 1000 deg^2 of sky. This is more than 20 times larger sample than…
We present direct $N$-body simulations of tidally filling 30,000 ${\rm M}_\odot$ star clusters orbiting between 10 kpc and 100 kpc in galaxies with a range of dark matter substructure properties. The time-dependent tidal force is determined…
The outskirts of globular clusters (GCs) simultaneously retain crucial information about their formation mechanism and the properties of their host galaxy. Thanks to the advent of precision astrometry both their morphological and kinematic…
We present results of the analysis of a set of images obtained in the field of the Milky Way bulge globular cluster NGC 6355 using the Dark Energy Camera, which is attached to the 4m Blanco telescope of the Cerro-Tololo Interamerican…
Using archival \hst WFPC2 data, we derive the metallicity distribution, luminosity function, and spatial structure of the globular cluster system around IC 4051, a giant E galaxy on the outskirts of the Coma cluster core. The metallicity…
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…
In order to understand the extended massive tidal tails of the globular cluster Pal5, its very low mass and velocity dispersion, and its size, which is much larger than the theoretical tidal radius, we performed more than 1000 N-body…
We present the results of a deep photometric study of the outer halo of NGC 1275, the highly active cD galaxy at the center of the Perseus cluster. We find a modest excess of faint ($R > 22.5$) starlike objects in its halo, indicating a…
In the last decade, observational studies have shown the existence of tidal streams in the outer part of many galactic globular clusters. The most striking examples of clusters with well defined tidal tails are represented by Palomar 5 and…
In this work, we use $N-$body simulations performed on GPU to trace the past 10 Gyr dynamical history of a globular cluster (GC) similar to NGC~6397 in the tidal field of a Milky Way-like galaxy and we compare our simulated GCs with data…
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 study of dynamical status of the globular cluster NGC 1851. A combination of multiwavelength space and ground-based data sets are used for the present analysis. In order to select the genuine cluster members, we used the…
ALMA imaging of the cold molecular medium in the nearby starburst galaxy NGC 1808 is presented. The observations reveal the distribution of molecular gas, traced by $^{12}$CO (1-0) and $^{12}$CO (3-2), and continuum (93 and 350 GHz) across…
We use deep images taken with the Advanced Camera for Surveys on board the Hubble Space Telescope of the disk galaxy NGC 891, to search for globular cluster candidates. This galaxy has long been considered to be a close analog in size and…
Spiral galaxies are thin and susceptible to being disrupted vertically. The largest star clusters, and nuclear starbursts, generate enough energy from winds and supernovae to send disk material to the halo. % METHODS Observations of edge-on…