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Related papers: Group analysis in the SSRS2 catalog

200 papers

We extract groups of galaxies from the SDSS Data Release 5 with the purpose of studying the supercluster-void network and environmental properties of groups therein. We use a modified friends-of-friends (FoF) method with adopted variable…

Astrophysics · Physics 2009-06-23 E. Tago , J. Einasto , E. Saar , E. Tempel , M. Einasto , J. Vennik , V. Müller

We present a galaxy group-finding algorithm, the Photo-z Probability Peaks (P3) algorithm, optimized for locating small galaxy groups using photometric redshift data by searching for peaks in the signal-to-noise of the local overdensity of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Bryan Gillis , Michael J. Hudson

We compute the luminosity function of galaxies in groups. The data consists in two samples of groups of galaxies selected in distance and redshift space comprising a total number of 66 groups. The assignment of galaxies to the groups were…

Astrophysics · Physics 2009-10-30 Hernán Muriel , Carlos A. Valotto , Diego G. Lambas

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

Clusters of galaxies in most previous catalogs have redshifts z<0.3. Using the photometric redshifts of galaxies from the Sloan Digital Sky Survey Data Release 6 (SDSS DR6), we identify 39,668 clusters in the redshift range 0.05< z <0.6…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Z. L. Wen , J. L. Han , F. S. Liu

We study the clustering properties of groups and of galaxies in groups in the DEEP2 Galaxy Redshift Survey dataset at z~1. Four clustering measures are presented: 1) the group correlation function for 460 groups with estimated velocity…

We use a modified version of the halo-based group finder developed by Yang et al. to select galaxy groups from the Sloan Digital Sky Survey (SDSS DR4). In the first step, a combination of two methods is used to identify the centers of…

Astrophysics · Physics 2009-07-28 Xiaohu Yang , H. J. Mo , Frank C. van den Bosch , Anna Pasquali , Cheng Li , Marco Barden

We present a study on the variations of the luminosity function of galaxies around clusters in a numerical simulation with semi-analytic galaxies, attempting to detect these variations in the 2dF Galaxy Redshift Survey. We subdivide the…

Astrophysics · Physics 2009-11-13 R. E. Gonzalez , N. D. Padilla , G. Galaz , L. Infante

We apply a halo-based group finder to four large redshift surveys, the 2MRS, 6dFGS, SDSS and 2dFGRS, to construct group catalogs in the low-redshift Universe. The group finder is based on that of Yang et al. but with an improved halo mass…

Astrophysics of Galaxies · Physics 2017-11-02 Seunghwan Lim , Houjun Mo , Yi Lu , Huiyuan Wang , Xiaohu Yang

We present a structure finding algorithm designed to identify galaxy groups in photometric redshift data sets: the probability friends-of-friends (pFoF) algorithm. This algorithm is derived by combining the friends-of-friends algorithm in…

Astrophysics · Physics 2009-11-13 I-hui Li , Howard K. C. Yee

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…

Astrophysics · Physics 2009-11-11 V. R. Eke , C. M. Baugh , S. Cole , C. S. Frenk , J. F. Navarro

Context. Friends-of-friends algorithms are a common tool to detect galaxy groups and clusters in large survey data. In order to be as precise as possible, they have to be carefully calibrated using mock catalogues. Aims. We create an…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-23 Christoph Saulder , Eelco van Kampen , Igor V. Chilingarian , Steffen Mieske , Werner W. Zeilinger

We present a group-galaxy cross-correlation analysis using a group catalog produced from the 16,500 spectra from the optical zCOSMOS galaxy survey. Our aim is to perform a consistency test in the redshift range 0.2 < z < 0.8 between the…

Galaxy groups likely to be virialized are identified within the CNOC2 intermediate redshift galaxy survey using an iterative method. The number-velocity dispersion relation is in agreement with the low-mass extrapolation of the cluster…

We create a new catalogue of groups and clusters for the 2dF GRS final release sample. We show that the variable linking length friends-of-friends (FoF) algorithms used so far yield groups with sizes that grow systematically with distance…

Astrophysics · Physics 2009-11-10 E. Tago , J. Einasto , M. Einasto , E. Saar

I review here past and present research on clusters and groups of galaxies within the Sloan Digital Sky Survey (SDSS). In particular, I discuss the C4 algorithm which is designed to search for clusters within a 7-dimensional data-space,…

Astrophysics · Physics 2007-05-23 Robert C. Nichol

We present the first measurement of the evolution of the galaxy group stellar mass function (GrSMF) to redshift z>~1 and low masses (M*>10^12 Msun). Our results are based on early data from the Carnegie-Spitzer-IMACS (CSI) Survey, utilizing…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Rik J. Williams , Daniel D. Kelson , John S. Mulchaey , Alan Dressler , Patrick J. McCarthy , Stephen A. Shectman

We measure the two-point redshift-space correlation function of loose groups of galaxies, xi_GG, for the combined CfA2 and SSRS2 surveys. Our combined group catalog constitutes the largest homogeneous sample available (885 groups). We…

Astrophysics · Physics 2007-05-23 M. Girardi , W. Boschin , L. da Costa , ;

We discuss an algorithm whereby the massive galaxy clusters detected in the SRG/eROSITA all-sky survey are identified and their photometric redshifts are estimated. For this purpose, we use photometric redshift estimates for galaxies and…

We introduce two new pair statistics, which relate close galaxy pairs to the merger and accretion rates. We demonstrate the importance of correcting these (and other) pair statistics for selection effects related to sample depth and…