相关论文: Mapping the galaxy NGC 4486 (M87) through its Glob…

We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the `Hubble Space Telescope (HST) UV Legacy Survey of Galactic globular clusters', to identify and characterize their…

Updated data of the 153 Galactic globular clusters are used to readdress fundamental parameters of the Milky Way. We build a reduced sample, decontaminated of the clusters younger than 10Gyr, those with retrograde orbits and/or evidence of…

The diffuse extended outer regions of galaxies are hard to study because they are faint, with typical surface brightness of 1% of the dark night sky. We can tackle this problem by using resolved star tracers which remain visible at large…

We study the Globular Cluster (GC) system of the nearby elliptical galaxy M87 using the newly available dataset with accurate kinematics (Strader et al.2011). We find evidence for three distinct sub-populations of GCs in terms of colours,…

We present the combined results of two investigations: a large-scale study of the globular cluster system (GCS) around NGC 1399, the central galaxy of the Fornax cluster, and a study of the GCSs around NGC 1374, NGC 1379 and NGC 1387, three…

Bimodal globular cluster metallicity distributions have now been seen in a handful of large ellipticals. Here we report the discovery of a bimodal distribution in the dominant group elliptical NGC 5846, using the Hubble Space Telescope's…

We present a photometric study of the field lenticular galaxy NGC 4546 using Gemini/GMOS imaging in g'r'i'z'. We perform a 2D image decomposition of the surface brightness distribution of the galaxy using GALFIT, finding that four…

We use the HB morphology of 48 Galactic GCs to study the radial distributions of the different stellar populations known to exist in globular clusters. Assuming that the (extremely) blue HB stars correspond to stars enriched in Helium and…

We investigate the structural, kinematical, and chemical properties of globular cluster systems (GCSs) in galaxies of different Hubble types in a self-consistent manner based on high-resolution cosmological N-body simulations combined with…

Using 3.6 and 4.5$\mu$m images of 73 late-type, edge-on galaxies from the S$^4$G survey, we compare the richness of the globular cluster populations of these galaxies to those of early type galaxies that we measured previously. In general,…

Globular cluster systems exhibit a bewildering variety of characteristics. No single scenario appears to be able to account for the wide range of specific globular cluster frequencies that are observed in galaxies of various types. The…

We present Lick line-index measurements of extragalactic globular clusters in seven early-type galaxies (NGC 1380, 2434, 3115, 3379, 3585, 5846, and 7192) with different morphological types (E-S0) located in field and group/cluster…

We have used WFPC2 on the Hubble Space Telescope to obtain F450W and F814W images of four cD galaxies (NGC 541 in Abell 194, NGC 2832 in Abell 779, NGC 4839 in Abell 1656 and NGC 7768 in Abell 2666) in the range 5400 < cz < 8100 km s^{-1}.…

The mass distribution and chemical composition of globular cluster (GC) systems preserve fossil record of the early stages of galaxy formation. The observed distribution of GC colors within massive early-type galaxies in the ACS Virgo…

The total mass M_GCS in the globular cluster (GC) system of a galaxy is empirically a near-constant fraction of the total mass M_h = M_bary + M_dark of the galaxy, across a range of 10^5 in galaxy mass. This trend is radically unlike the…

We present new (B,I) photometry for the globular cluster systems in eight Brightest Cluster Galaxies (BCGs), obtained with the ACS/WFC camera on the Hubble Space Telescope. In the very rich cluster systems that reside within these giant…

We present radial velocities for 144 globular clusters around the Virgo gE NGC 4472 (M49), and ages and metallicities from co-added spectra of 131 clusters. We confirm our earlier finding that the metal-poor clusters have a significantly…

We present Sloan g and i imaging from the GMOS instrument on the Gemini North telescope for the globular cluster (GC) system around the Virgo galaxy NGC 4649 (M60). Our three pointings, taken in good seeing conditions, cover an area of…

The spectroscopic and photometric signals of the star-to-star abundance variations found in globular clusters seem to be correlated with global parameters like the cluster's metallicity, mass and age. Understanding this behaviour could…

The most massive elliptical galaxies show a prominent multi-modality in their globular cluster system color distributions. Understanding the mechanisms which lead to multiple globular cluster sub-populations is essential for a complete…