相关论文: The faint globular cluster in the dwarf galaxy And…
We present the discovery of three faint dwarf galaxies and a globular cluster in the halo of the Andromeda galaxy (M31), found in our MegaCam survey that spans the southern quadrant of M31, from a projected distance of ~50 kpc to \~150 kpc.…
Besides giant elliptical galaxies, a number of low-mass stellar systems inhabit the cores of galaxy clusters, such as dwarf elliptical galaxies (dEs/dSphs), ultra-compact dwarf galaxies (UCDs), and globular clusters. The detailed…
Recent work on globular cluster systems in dwarf galaxies outside the Local Group is reviewed. Recent large imaging surveys with the Hubble Space Telescope and follow-up spectroscopy with 8-m class telescopes now allow us to compare the…
Data are presently available on the luminosities and half-light radii of 101 globular clusters associated with low-luminosity parent galaxies. The luminosity distribution of globulars embedded in dwarf galaxies having $M_{v} > -16$ is found…
In the last decade we witness an advent of new types of dwarf stellar systems in cluding ultra-compact dwarfs, ultra-faint dwarf spheroidals, and exotic globular clusters, breaking the old simple paradigm for dwarf galaxies and globular…
We report on the discovery of three new dwarf galaxies in the Local Group. These galaxies are found in new CFHT/MegaPrime g,i imaging of the south-western quadrant of M31, extending our extant survey area to include the majority of the…
The nature of the dwarf galaxy population as a function of location in the cluster and within different environments is investigated. We have previously described the results of a search for low surface brightness objects in data drawn from…
The recently discovered vast thin plane of dwarf satellites orbiting the Andromeda Galaxy (M31) adds to the mystery of the small scale distribution of the Local Group's galaxy population. Such well defined planar structures are apparently…
The majority of the globular clusters associated with the Sagittarius dwarf galaxy are faint. In this respect it differs significantly from the globular cluster systems surrounding typical giant galaxies. The observation that most of…
A new compilation of data on Local Group members shows that low-luminosity early-type galaxies are, at the 99% confidence level, more strongly concentrated in the M 31, and Galactic sub-clumps, than are dwarf irregular galaxies. It is not…
With targeted imaging of groups in the local volume, the regions of collapse around bright galaxies can be clearly identified by the distribution of dwarfs and luminosity functions can be established to very faint levels. In the case of the…
The origin and formation of globular clusters has remained a mystery. We present a formation scenario for ancient globular cluster-like objects that form in ultra-high resolution simulations (smallest cell size $<0.1\,\mathrm{pc}$, mass…
An order of magnitude more dwarf galaxies are expected to inhabit the Local Group, based on currently accepted galaxy formation models, than have been observed. This discrepancy has been noted in environments ranging from the field to rich…
Morphological classification of dwarf galaxies into early and late type, though can account for some of their origin and characteristics but does not help to study their formation mechanism. So an objective classification using Principal…
We present a new photometric catalog of 326 candidate globular clusters (GCs) in the nearby spiral galaxy M101, selected from B, V, and I Hubble Space Telescope Advanced Camera for Surveys images. The luminosity function (LF) of these…
Traditionally globular clusters and dwarf spheroidal galaxies have been distinguished by using one or more of the following criteria: (1) mass, (2) luminosity, (3) size, (4) mass-to-light ratio and (5) spread in metallicity. However, a few…
In this contribution, first results of deep VLT photometry (V,I) in the central region of the Hydra I and Centaurus galaxy clusters are presented. In both galaxy clusters, many star clusters have been identified down to the turnover…
The recent detection of two faint and extended star clusters in the central regions of two Local Group dwarf galaxies, Eridanus II and Andromeda XXV, raises the question of whether clusters with such low densities can survive the tidal…
I review recent measurements of the faint end of the galaxy luminosity function in galaxy clusters. Evidence is presented that the luminosity function of galaxies in the central parts of clusters is remarkably constant between clusters and…
Our current knowledge of M31's dwarf spheroidal companions is reviewed. Two topics of recent interest constitute the bulk of this review. First, color-magnitude diagrams reaching below the horizontal branch have been constructed for two M31…