Related papers: Quantifying the Projected Suppression of Cluster E…
We provide the first direct lifting of the mass/anisotropy degeneracy for a cluster of galaxies, by jointly fitting the line of sight velocity dispersion and kurtosis profiles of the Coma cluster, assuming an NFW tracer density profile, a…
We present 3D kinematic observations of stars within the central 0.5 pc of the Milky Way nuclear star cluster using adaptive optics imaging and spectroscopy from the Keck telescopes. Recent observations have shown that the cluster has a…
In this paper we use the two-dimensional (2D) version of a new analytical gravitational model in order to explore the orbital as well as the escape dynamics of the stars in a barred galaxy composed of a spherically symmetric central…
We identify low redshift clusters and groups in the Sloan Digital Sky Survey (SDSS) and estimate their kinetic and correlation potential energies. We compare the distribution of these energies to the predictions by Yang and Saslaw (2012)…
Analyzing the halo and galaxy catalogs from the Millennium simulations at redshifts $z=0,\ 0.5,\ 1$, we determine the alignment profiles of cluster galaxies by measuring the average alignments between the major axes of the pseudo inertia…
We compare the distribution of internal velocity dispersions of galaxy clusters for an observational sample to those obtained from a set of N-body simulations of seven COBE-normalised cosmological scenarios: the standard CDM (SCDM) and a…
We determine the slope of the near infrared extinction power law (A$_{\lambda} \propto \lambda^{-\alpha}$) for 8 regions of the Galaxy between l$\sim27^{\circ}$ and $\sim100^{\circ}$. UKIDSS Galactic Plane Survey data are compared, in…
Galaxy clusters are the most recent products of hierarchical accretion over cosmological scales. The gas accreted from the cosmic field is thermalized inside the cluster halo. Gas entropy and pressure are expected to have a self-similar…
We investigate the anisotropy of the stellar velocity dispersions within the effective radius, $R_{\rm e}$, in 24 ATLAS$^{\rm 3D}$ pure-bulge galaxies, 16 of which are kinematic slow rotators (SRs). We allow the spherical anisotropy…
We present a statistical system that can be used in the study of cluster populations. The basis of our approach is the construction of synthetic cluster color-magnitude-radius diagrams (CMRDs), which we compare with the observed data using…
We develop a method for reconstructing the two-dimensional, projected gravitational potential of galaxy clusters from observed line-of-sight velocity dispersions of cluster galaxies. It is the third of an intended series of papers aiming at…
Numerical simulations indicate that cosmological halos display power-law radial profiles of pseudo phase-space density (PPSD), Q=rho/sigma^3, where rho is mass density and sigma velocity dispersion. We test these predictions using the…
The average mass density profile measured in the CNOC cluster survey is well described with the analytic form rho(r)=A/[r(r+a_rho)^2], as advocated on the basis on n-body simulations by Navarro, Frenk & White. The predicted core radii are…
In the $\Lambda$CDM paradigm, the masses of the galaxy clusters inferred using background galaxies via weak-lensing shear should agree with the masses measured using the galaxy projected radius-velocity phase-space data via the escape…
Under the assumption that the gas mass fraction of galaxy clusters estimated out to an outer hydrostatic radius is constant, it is possible to constrain the cosmological parameters by using the angular diameter distance relation with…
The escape mechanism of orbits in a star cluster rotating around its parent galaxy in a circular orbit is investigated. A three degrees of freedom model is used for describing the dynamical properties of the Hamiltonian system. The…
The study of the kinematics of galaxies within clusters or groups has the limitation that only one of the three velocity components and only two of the three spatial components of a galaxy position in six-dimensional phase space can…
Galaxy cluster peculiar velocities can be inferred from high-sensitivity, high-resolution multiple-frequency observations in the 30 to 400 GHz range. While galaxy cluster counts and power spectra are sensitive to the growth factor, peculiar…
In this study we use simulations of 128$^3$ particles to study the ellipticity and orientation of clusters of galaxies in N-body simulations of differing power-law initial spectra (P(k) \propto k^n ,n = +1, 0, -1, -2$), and density…
We use an unprecedented data-set of about 600 redshifts for cluster members, obtained as part of a VLT/VIMOS large programme, to constrain the mass profile of the z=0.44 cluster MACS J1206.2-0847 over the radial range 0-5 Mpc (0-2.5 virial…