相关论文: NGC1600 - Cluster or Field Elliptical?
We analyze the internal velocity dispersions of a sample of 172 nearby galaxy clusters (z < 0.15), each of which has at least 30 available galaxy redshifts, and spans a large richness range. Cluster membership selection is based on…
We present the results of an X-ray mass analysis of the early-type galaxy NGC 4636, using Chandra data. We have compared the X-ray mass density profile with that derived from a dynamical analysis of the system's globular clusters (GCs).…
In this work we study the shape of the projected surface mass density distribution of galaxy clusters using weak-lensing stacking techniques. In particular, we constrain the average aligned component of the projected ellipticity,…
An excellent candidate for a young elliptical, or `protoelliptical' galaxy is NGC 1700. Here we present new B, V and I band imaging using the Keck telescope and reanalyse existing V and I band images from the Hubble Space Telescope. After…
What is the role of clusters of galaxies in probing the large-scale velocity field of the universe? We investigate the distribution of peculiar velocities of clusters of galaxies in the popular low-density ($\Omega=0.3$) flat…
The velocity dispersion of the ultra diffuse galaxy NGC1052-DF2 was found to be $\sigma_{\rm gc}=7.8^{+5.2}_{-2.2} \ \mathrm{kms^{-1}}$, much lower than expected from the stellar mass -- halo mass relation and nearly identical to the…
Galaxy cluster mass distribution are potentially useful probes of $\Omega_0$ and the nature of the dark matter. Large clusters will distort the observed shapes of background galaxies through gravitational lensing allowing the measurement of…
We present an extension of our previous research on the early-type galaxy population of the Antlia cluster (d ~ 35 Mpc), achieving a total coverage of ~ 2.6 deg x deg and performing surface photometry for ~300 galaxies, 130 of which are new…
We study the kinematics and dynamics of the globular cluster system of NGC 1399, the central galaxy of the Fornax cluster. The observational data consists of medium resolution spectra, obtained at the Very Large Telescope. Our sample…
We have carried out a systematic, homogeneous comparison of optical and near-infrared dispersions. Our magnitude-limited sample of early-type galaxies in the Fornax cluster comprises 11 elliptical and 11 lenticular galaxies more luminous…
NGC 205 is the nearest example of a dwarf elliptical (dE) galaxy and the prototype of this enigmatic galaxy class. Photometric evidence suggests that NGC 205, a close satellite of the M31 galaxy, is tidally interacting with its parent…
Infrared emission has been detected from normal elliptical galaxies and from clusters of galaxies at 60um and 100um with the IRAS satellite. In both cases, the emission has the characteristics of cool dust with a temperature near 30K. For…
We use a new non-parametric Bayesian approach to obtain the most probable mass distributions and circular velocity curves along with their confidence ranges, given deprojected density and temperature profiles of the hot gas surrounding…
The galaxy group NGC 5044 consists of a luminous giant elliptical galaxy surrounded by a cluster of approximately 160 low luminosity and dwarf galaxies, mostly of early type. The cumulative projected radial distribution of dwarf galaxies in…
We present new metallicity estimates for globular cluster (GC) candidates in the Sd spiral NGC 300, one of the nearest spiral galaxies outside the Local Group. We have obtained optical spectroscopy for 44 Sculptor Group GC candidates with…
We have analyzed high velocity resolution HI synthesis observations of the nearly face-on Sc galaxy NGC 1232. The neutral gas distribution extends well beyond the optical extent of the galaxy. As expected, local peaks in the HI column…
Redshifts of several galaxies thought to be associated with NGC 326 are determined. The results confirm the presence of a cluster and find a mean redshift of z = 0.0477 +/- 0.0007 and a line-of-sight velocity dispersion sigma_{z} = 599…
We recently published velocity measurements of luminous globular clusters in the galaxy NGC1052-DF2, concluding that it lies far off the canonical stellar mass - halo mass relation. Here we present a revised velocity for one of the globular…
We investigate the globular cluster system of the isolated elliptical NGC 7796, present new photometry of the galaxy, and use published kinematical data to constrain the dark matter content. Deep images in B and R, obtained with the VIsible…
We define a large sample of galaxies for use in a study of the fundamental plane in the intermediate redshift cluster CL1358+62 at $z=0.33$. We have analyzed high resolution spectra for 55 members of the cluster. The data were acquired with…