Related papers: The Observational Mass Function of Loose Galaxy Gr…
We present a new determination of the mass function of galaxy clusters, based on optical virial mass estimates for a large sample of 152 nearby (z\le0.15) Abell-ACO clusters, as provided by Girardi et al. (1998). This sample includes both…
We study the mass-to-light ratio of galaxy systems from poor groups to rich clusters, and present for the first time a large database for useful comparisons with theoretical predictions. We extend a previous work, where B_j band…
A new X-ray selected and X-ray flux-limited galaxy cluster sample is presented. Based on the ROSAT All-Sky Survey the 63 brightest clusters with galactic latitude |bII| >= 20 deg and flux fx(0.1-2.4 keV) >= 2 * 10^{-11} ergs/s/cm^2 have…
The abundance of galaxy clusters as a function of mass is determined using the 2dFGRS Percolation-Inferred Galaxy Group (2PIGG) catalogue. This is used to estimate the amplitude of the matter fluctuation spectrum, parametrised by the linear…
We present a maximum-likelihood weak lensing analysis of the mass distribution in optically selected spectroscopic Galaxy Groups (G$^3$Cv5) in the Galaxy And Mass Assembly (GAMA) survey, using background Sloan Digital Sky Survey (SDSS)…
A galaxy group catalog is built from the sample of the 2MASS Redshift Survey almost complete to Ks=11.75 over 91% of the sky. Constraints in the construction of the groups were provided by scaling relations determined by close examination…
We present the first measurement of the mass function of galaxy clusters based directly on cluster masses derived from observations of weak gravitational lensing. To investigate the degree of sample incompleteness resulting from the X-ray…
We evaluate in a homogeneous way the optical masses of 170 nearby clusters (z< 0.15). The sample includes both data from the literature and the new ENACS data (Katgert et al. 1996, 1998). On the assumption that mass follows the galaxy…
We have determined the mass function of loose groups of galaxies in the Las Campanas Redshift Survey. Loose groups of galaxies in the LCRS range in mass from $M \sim 10^{12} {\rm M}_{\sun}$ to $10^{15} {\rm M}_{\sun}$. We find that the…
We present an estimate of the galaxy stellar mass function and its division by morphological type in the local (0.025 < z < 0.06) Universe. Adopting robust morphological classifications as previously presented (Kelvin et al.) for a sample…
The 2dFGRS Percolation-Inferred Galaxy Group (2PIGG) catalogue of ~29000 objects is used to study the luminous content of galaxy systems of various sizes. Mock galaxy catalogues constructed from cosmological simulations are used to gauge…
The mass derived from gravitational lensing reflects the total mass contained in the lensing system, independent of the specific matter contents and states. A comparison of the dynamical masses from hydrostatic equilibrium with the…
A study of the group properties of galaxies in our immediate neighborhood provides a singular opportunity to observationally constrain the halo mass function, a fundamental characterization of galaxy formation. Detailed studies of…
We study morphology and luminosity segregation of galaxies in loose groups. We analyze the two catalogs of groups which have been identified in the Nearby Optical Galaxy (NOG) sample, by means of hierarchical and percolation…
The mass function of galaxies and clusters of galaxies can be derived observationally based on different types of observations. In this study we test if these observations can be combined to a consistent picture which is also in accord with…
We report the discovery of 12 new fossil groups of galaxies, systems dominated by a single giant elliptical galaxy and cluster-scale gravitational potential, but lacking the population of bright galaxies typically seen in galaxy clusters.…
Two algorithms for the identification of galaxy groups from redshift surveys are tested by application to simulated data derived from N-body simulation. The accuracy of the membership assignments by these algorithms is studied in a…
We determine the mass functions (MFs) and the dynamical parameters of 15 nearby open clusters (OCs) using the unprecedented data set of the Gaia Early Data Release 3. We select the members of each cluster by combining the photometric…
We present a large catalog of loose groups of galaxies in the Southern Galactic Hemisphere, selected from the Perseus-Pisces redshift Survey (PPS). Particular care is taken in order to obtain group samples as homogeneous as possible to…
In this paper we describe the Nearby Optical Galaxy (NOG) sample, which is a complete, distance-limited ($cz\leq$6000 km/s) and magnitude-limited (B$\leq$14) sample of $\sim$7000 optical galaxies. The sample covers 2/3 (8.27 sr) of the sky…