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Related papers: The Structure of 2MASS Galaxy Clusters

200 papers

Several statistics are applied to groups and galaxies in groups in the Two degree Field Galaxy Redshift Survey. Firstly we estimate the luminosity functions for different subsets of galaxies in groups. The results are well fitted by a…

Astrophysics · Physics 2009-11-07 H. J. Martinez , A. Zandivarez , M. E. Merchan , M. J. L. Dominguez

According to the current cosmological paradigm, large scale structures form hierarchically in the Universe. Clusters of galaxies grow through a continuous accretion of mass. Nevertheless, the rate and manner of mass accretion events are…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 J. Alfonso L. Aguerri , Ruben Sanchez-Janssen

We use catalogues of superclusters of galaxies from the 2dF Galaxy Redshift Survey to study the properties of galaxies in superclusters. We compare the properties of galaxies in high and low density regions of rich superclusters, in poor…

The proper motions of stars in the outskirts of globular clusters are used to estimate cluster velocity dispersion profiles as far as possible within their tidal radii. We use individual color-magnitude diagrams to select high probability…

Astrophysics of Galaxies · Physics 2021-12-08 Raymond G. Carlberg , Carl J. Grillmair

Filaments of galaxies are known to stretch between galaxy clusters at all redshifts in a complex manner. In this Letter, we present an analysis of the frequency and distribution of inter-cluster galaxy filaments selected from the 2dF Galaxy…

Astrophysics · Physics 2009-11-10 Kevin A. Pimbblet , Michael J. Drinkwater , Mary C. Hawkrigg

We study the systematic bias introduced when selecting the spectroscopic redshifts of brighter cluster galaxies to estimate the velocity dispersion of galaxy clusters from both simulated and observational galaxy catalogues. We select…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 L. Old , M. E. Gray , F. R. Pearce

Based on optical and X-ray data for a sample of 34 relaxed rich clusters of galaxies with redshifts of 0.1-0.9, we studied relative spatial distributions of the two major baryon contents, the cluster galaxies and the hot plasmas. Using…

The infall regions of galaxy clusters represent the largest gravitationally bound structures in a $\Lambda$CDM universe. Measuring cluster mass profiles into the infall regions provides an estimate of the ultimate mass of these haloes. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Kenneth Rines , Margaret J. Geller , Antonaldo Diaferio , Michael J. Kurtz

We have measured the surface density of galaxies toward 14 X-ray-selected cluster candidates at redshifts greater than z=0.46, and we show that they are associated with rich galaxy concentrations. We find that the clusters range between…

Astrophysics · Physics 2009-11-06 B. R. McNamara , A. Vikhlinin , A. Hornstrup , H. Quintana , K. Whitman , W. Forman , C. Jones

Luminosity functions have been determined for star cluster populations in 20 nearby (4-30 Mpc), star-forming galaxies based on ACS source lists generated by the Hubble Legacy Archive. Comparisons are made with other recently generated…

Astrophysics of Galaxies · Physics 2015-06-19 Bradley C. Whitmore , Rupali Chandar , Ariel S. Bowers , Soeren Larsen , Kevin Lindsay , Asna Ansari , Jessica Evans , .

We used star density maps obtained from 2MASS to obtain a sample of star clusters in the entire Galactic Plane with |b|<20deg. A total of 1788 star cluster candidates are identified in this survey. Among those are 681 previously known open…

Astrophysics · Physics 2009-11-11 D. Froebrich , A. Scholz , C. L. Raftery

We investigate properties of superclusters of galaxies found on the basis of the 2dF Galaxy Redshift Survey, and compare them with properties of superclusters from the Millennium Simulation. We study the dependence of various…

We present a modified adaptive matched filter algorithm designed to identify clusters of galaxies in wide-field imaging surveys such as the Sloan Digital Sky Survey. The cluster-finding technique is fully adaptive to imaging surveys with…

Astrophysics · Physics 2009-11-13 Feng Dong , Elena Pierpaoli , James E. Gunn , Risa H. Wechsler

To test whether clusters have rising mass to light ratios at large radii and to estimate the amplitude of the density fluctuation spectrum on the scale of 10\hmpc\ the Canadian Network for Observational Cosmology (CNOC) cluster…

Astrophysics · Physics 2007-05-23 Carlberg

We have analyzed the galaxy number density and luminosity density profiles of rich clusters of galaxies from redshifts z=0 to z=0.5. We show that the luminosity profile computed with bright galaxies is significantly cusped in the center of…

Astrophysics · Physics 2009-11-06 C. Adami , A. Mazure , M. P. Ulmer , C. Savine

The distribution of galaxies in position and velocity around the centers of galaxy clusters encodes important information about cluster mass and structure. Using the maxBCG galaxy cluster catalog identified from imaging data obtained in the…

The MS1224+20 cluster of galaxies is a high luminosity X-ray source at z=0.325. To compare the lensing mass to the virial mass we have completed a uniform, high precision redshift survey over a field of $7\arcm\times9\arcm$, obtaining 75…

Astrophysics · Physics 2009-10-22 R. G. Carlberg , H. K. C. Yee , E. Ellingson

This paper, the third in a series, investigates the scaling relations between optical richness, weak-lensing mass, and Compton $Y$ for a sample of galaxy clusters selected purely by the effect of their gravitational potential on the shapes…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 S. Andreon , M. Radovich

Globular clusters will be present at high redshifts, near the very beginning of the galaxy formation process. Stellar evolution ensures that they will be much more luminous than today. We show that the redshift distribution at nano-Jansky…

Astrophysics · Physics 2009-11-07 R. G. Carlberg

Clusters of galaxies are at the intersection of cosmic filaments and are still accreting galaxies and groups along these preferential directions, but, because of their relatively low contrast on the sky, they are difficult to detect (unless…