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Related papers: Compact Group Selection From Redshift Surveys

200 papers

It is often believed that isolated compact groups (CGs) of galaxies are special systems, but only a few studies have compared CGs to regular groups. We study the global properties and internal correlations of a volume- and…

Astrophysics of Galaxies · Physics 2025-07-23 Matthieu Tricottet , Gary A. Mamon , Eugenia Díaz-Giménez

We use the outputs of a semi-analytical model of galaxy formation run on the Millennium Simulation to investigate the prevalence of 3D compact groups (CGs) of galaxies from $z = 11$ to 0. Our publicly available code identifies CGs using the…

We present an automated method to detect populations of groups in galaxy redshift catalogs. This method uses both analysis of the redshift distribution along lines of sight in fixed cells to detect elementary structures and a…

Astrophysics · Physics 2009-11-07 C. Adami , A. Mazure

A ``friends-of-friends'' percolation algorithm has been used to extract a catalogue of dn/n = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalogue contains 1495 groups and…

A compact group (CG) is a kind of special galaxy system where the galaxy members are separated at the distances of the order of galaxy size. The strong interaction between the galaxy members makes CGs ideal labs for studying the…

Astrophysics of Galaxies · Physics 2021-01-19 Yunliang Zheng , Shiyin Shen

Compact groups of galaxies provide a unique environment to study the mechanisms by which star formation occurs amid continuous gravitational encounters. We present 2MASS (JHK), Spitzer IRAC (3.5-8 micron) and MIPS (24 micron) observations…

The nature of compact groups (CGs) of galaxies, apparently so dense that the galaxies often overlap, is still a subject of debate: Are CGs roughly as dense in 3D as they appear in projection? Or are they caused by chance alignments of…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 G. A. Mamon , E. Diaz-Gimenez

A comprehensive study on compactness has been carried out on the 2dF Galaxy Group Catalogue constructed by Merch\'an & Zandivarez. The compactness indexes defined in this work take into account different geometrical constraints in order to…

Astrophysics · Physics 2009-11-07 A. Zandivarez , M. J. L. Dominguez , C. J. Ragone , H. Muriel , H. J. Martinez

Compact groups of galaxies appear to be extremely dense, making them likely sites of intense galaxy interaction, while their small populations make them relatively simple to analyze. In order to search for optical interaction tracers such…

Astrophysics · Physics 2009-10-28 Rachel A. Pildis , Joel N. Bregman , James M. Schombert

Multi-wavelength observations of Hickson's Compact Groups (HCGs) have shown that many of these groups are physical bound structures and are in different stage of evolution, from spiral-dominated systems to almost merged objects. Very few…

Astrophysics · Physics 2009-11-13 E. Pompei , M. Dahlem , A. Iovino

We present the largest publicly available catalogue of compact groups of galaxies identified using the original selection criteria of Hickson, selected from the Sixth Data Release (DR6) of the Sloan Digital Sky Survey (SDSS). We identify…

Astrophysics · Physics 2009-11-13 Alan McConnachie , David Patton , Sara Ellison , Luc Simard

We investigate the performance of group finding algorithms that reconstruct galaxy groups from the positional information of tracer galaxies that are observed in redshift surveys carried out with multiplexed spectrographs. We use mock…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-28 Tobias J. Looser , Simon J. Lilly , Larry P. T. Sin , Bruno M. B. Henriques , Roberto Maiolino , Michele Cirasuolo

A "friends-of-friends" percolation algorithm has been used to extract a catalogue of drho/rho = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalogue contains 1495 groups and…

Compact groups (CGs) of galaxies -- relatively poor groups of galaxies in which the typical separations between members is of the order of a galaxy diameter -- offer an exceptional laboratory for the study of dense galaxian environments…

Using the TNG100 cosmological simulation, we study the formation and evolution of compact groups of galaxies. Over a redshift range of $0 \lesssim z \lesssim 0.2$, we identify these compact groups as FoF galaxy groups with high mean surface…

Astrophysics of Galaxies · Physics 2025-08-20 Bruno M. Celiz , José A. Benavides , Mario G. Abadi

We examine the properties of galaxies in compact groups identified in a mock galaxy catalogue based upon the Millennium Run simulation. The overall properties of groups identified in projection are in general agreement with the best…

Astrophysics · Physics 2009-11-13 Crystal M. Brasseur , Alan W. McConnachie , Sara L. Ellison , David R. Patton

Compact groups of galaxies are devised as extreme environments where interactions may drive galaxy evolution. In this work, we analysed whether the luminosities of galaxies inhabiting compact groups differ from those of galaxies in loose…

Astrophysics of Galaxies · Physics 2022-05-25 Ariel Zandivarez , Eugenia Diaz-Gimenez , Antonela Taverna

From R-band images of 39 Hickson compact groups (HCGs), we use galaxy counts to determine a luminosity function extending to M_R=-14.0, approximately two magnitudes deeper than previous compact group luminosity functions. We find that a…

Astrophysics · Physics 2009-10-30 Sally D. Hunsberger , Jane C. Charlton , Dennis Zaritsky

We use dense redshift surveys to explore the properties of galaxy clusters selected from the redMaPPer catalog of overdensities of red galaxies. Our new survey, HeCS-red (Hectospec Cluster Survey of red-sequence selected clusters), includes…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-15 Kenneth J. Rines , Margaret J. Geller , Antonaldo Diaferio , Ho Seong Hwang , Jubee Sohn

We report the results of an almost complete survey of the X-ray properties of Hickson's compact galaxy groups with the ROSAT PSPC. Diffuse X-ray emission is detected from 22 groups. We infer that hot intragroup gas is present in $\gtsimm…

Astrophysics · Physics 2015-06-24 T. J. Ponman , P. D. Bourner , H. Ebeling , H. Bohringer