Related papers: Total mass slopes and enclosed mass constrained by…
Scaling relations for globular clusters (GC) differ from scaling relations for pressure supported (elliptical) galaxies. We show that two-body relaxation is the dominant mechanism in shaping the bivariate dependence of density on mass and…
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 analyze the internal dynamics of 43 non-interacting clusters which are selected from the 2dF Galaxy Redshift Survey 100k public release. We join together the 43 clusters into an ensemble cluster by appropriately scaling their galaxy…
Recent studies of nearby globular clusters have discovered excess dark mass in their cores, apparently in an extended distribution, and simulations indicate that this mass is composed mostly of white dwarfs (respectively stellar-mass black…
We investigate in massive early-type galaxies the variation of their two-dimensional central fraction of dark over total mass and dark matter density as a function of stellar mass, central stellar velocity dispersion, effective radius, and…
Globular clusters (GCs) lie scattered around the inner $40\%$ of the virial radius of galaxy clusters, potentially being excellent tracers of the underlying mass distribution. In this paper, we present a statistical method based on assuming…
We present a weak lensing analysis of a sample of SDSS Compact Groups (CGs). Using the measured radial density contrast profile, we derive the average masses under the assumption of spherical symmetry, obtaining a velocity dispersion for…
We present the results from a wide-field imaging study of globular cluster (GC) systems in three early-type galaxies. Combinations of Subaru/Suprime-Cam, CFHT/MegaCam and HST/WFPC2/ACS data were used to determine the GC system properties of…
We present new analytical distribution functions for anisotropic spherical galaxies. They have the density profiles of the gamma-models, which allow a wide range of central density slopes, and are widely used to fit elliptical galaxies and…
Context. Globular clusters (GCs) are suggested to host many stellar-mass black holes (BHs) at their centers, thus resulting in ideal testbeds for BH formation and retention theories. BHs are expected to play a major role in GC structural…
Strong gravitational lensing and stellar dynamics provide two complementary and orthogonal constraints on the density profiles of galaxies. Based on spherically symmetric, scale-free, mass models, it is shown that the combination of both…
We study the mass and anisotropy distribution of the giant elliptical galaxy NGC 5846 using stars, as well as the red and blue globular cluster (GC) subpopulations. We break degeneracies in the dynamical models by taking advantage of the…
We use radial velocities of member stars and cluster surface brightness profiles to non-parametrically determine the mass density profiles and isotropic phase-space distribution functions $f(E)$ for the globular clusters M15 (NGC7078),…
Galaxy clusters are unique laboratories for studying astrophysical processes and their impact on gas kinematics. Despite their importance, the full complexity of gas motion within and around clusters remains poorly known. This paper is part…
We present analysis of bulk and random gas motions in the intracluster medium using high-resolution Eulerian cosmological simulations of sixteen simulated clusters, including both very relaxed and unrelaxed systems and spanning a virial…
High-resolution N-body simulations are used to investigate systematic trends in the mass profiles and total masses of clusters as derived from 3 simple estimators: (1) the weak gravitational lensing shear field under the assumption of an…
We discuss constraints on the formation of multiple populations in globular clusters (GCs) imposed by their present-day kinematics (velocity dispersion and anisotropy) and spatial distribution. We argue that the observational evidence…
We use 118 strong gravitational lenses observed by the SLACS, BELLS, LSD and SL2S surveys to constrain the total mass profile and the profile of luminosity density of stars (light-tracers) in elliptical galaxies up to redshift $z \sim 1$.…
The near-universal turnover mass of the present-day globular cluster mass function (GCMF), $M_{\rm TO} \sim 2 \times 10^5\ {\rm M_\odot}$, is a well established observational feature across galaxies of different types and masses, providing…
We develop and implement a model to analyze the internal kinematics of galaxy clusters that may contain subpopulations of galaxies that do not independently trace the cluster potential. The model allows for substructures within the cluster…