Identifying galaxy groups at high redshift from incomplete spectroscopic data – I. The group finder and application to zCOSMOS

  title={Identifying galaxy groups at high redshift from incomplete spectroscopic data – I. The group finder and application to zCOSMOS},
  author={Kai Wang and H. J. Mo and Cheng Li and Jiacheng Meng and Yangyao Chen},
  journal={Monthly Notices of the Royal Astronomical Society},
Identifying galaxy groups from redshift surveys of galaxies plays an important role in connecting galaxies with the underlying dark matter distribution. Current and future high-$z$ spectroscopic surveys, usually incomplete in redshift sampling, present both opportunities and challenges to identifying groups in the high-$z$ Universe. We develop a group finder that is based on incomplete redshift samples combined with photometric data, using a machine learning method to assign halo masses to… 

Measuring galaxy abundance and clustering at high redshift from incomplete spectroscopic data: Tests on mock catalogs and application to zCOSMOS

The number density and correlation function of galaxies are two key quantities to characterize the distribution of the observed galaxy population. High-$z$ spectroscopic surveys, which usually

Biased Tracer Reconstruction with Halo Mass Information

Plenty of crucial information about our universe is encoded in the cosmic large-scale structure (LSS). However, extractions of this information are usually hindered by the nonlinearities of the LSS,

Groups and Protocluster Candidates in the CLAUDS and HSC-SSP Joint Deep Surveys

Using the extended halo-based group finder developed by Yang et al., which is able to deal with galaxies via spectroscopic and photometric redshifts simultaneously, we construct galaxy group and

Finding protoclusters to trace galaxy evolution – I. The finder and its performance

We develop a method to identify proto-clusters based on dark matter halos represented by galaxy groups selected from surveys of galaxies at high redshift. We test the performance of this method on

Optimizing high-redshift galaxy surveys for environmental information

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

Towards testing the theory of gravity with DESI: summary statistics, model predictions and future simulation requirements

Shortly after its discovery, General Relativity (GR) was applied to predict the behavior of our Universe on the largest scales, and later became the foundation of modern cosmology. Its validity has



Galaxy groups in the low-redshift Universe

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

The DEEP2 Galaxy Redshift Survey: First Results on Galaxy Groups

We use the first 25% of the DEEP2 Galaxy Redshift Survey spectroscopic data to identify groups and clusters of galaxies in redshift space. The data set contains 8370 galaxies with confirmed redshifts

Percolation Galaxy Groups and Clusters in the SDSS Redshift Survey: Identification, Catalogs, and the Multiplicity Function

We identify galaxy groups and clusters in volume-limited samples of the Sloan Digital Sky Survey (SDSS) redshift survey, using a redshift-space friends-of-friends algorithm. We optimize the


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

The DEEP2 Galaxy Redshift Survey: Clustering of Groups and Group Galaxies at z ~ 1

We study the clustering properties of groups and of galaxies in groups in the DEEP2 Galaxy Redshift Survey data set at z ~ 1 in three separate fields covering a total of 2 deg2. Four measures of

Group-finding with photometric redshifts: the photo-z probability peaks algorithm

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

Density profiles of galaxy groups and clusters from SDSS galaxy–galaxy weak lensing

We present results of a measurement of the shape of the density profile of galaxy groups and clusters traced by 43 335 Luminous Red Galaxies (LRGs) with spectroscopic redshifts from the Sloan Digital

The galaxy luminosity function in groups and clusters: the faint-end upturn and the connection to the field luminosity function

We characterize the luminosity functions of galaxies residing in $z\sim0$ groups and clusters over the broadest ranges of luminosity and mass reachable by the Sloan Digital Sky Survey. Our

A halo-based galaxy group finder: calibration and application to the 2dFGRS

We use the halo occupation model to calibrate galaxy group finders in magnitude limited redshift surveys. Because, according to the current scenario of structure formation, galaxy groups are

Galaxy Groups in the SDSS DR4. II. Halo Occupation Statistics

We investigate various galaxy occupation statistics of dark matter halos using a large galaxy group catalog constructed from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) with an adaptive