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Related papers: Optical Detection of Galaxy Clusters

200 papers

We present a comparison between two optical cluster finding methods: a matched filter algorithm using galaxy angular coordinates and magnitudes, and a percolation algorithm using also redshift information. We test the algorithms on two mock…

Astrophysics · Physics 2009-11-10 D. Rizzo , C. Adami , S. Bardelli , A. Cappi , E. Zucca , B. Guiderdoni , G. Chincarini , A. Mazure

We develop a galaxy cluster finding algorithm based on spectral clustering technique to identify optical counterparts and estimate optical redshifts for X-ray selected cluster candidates. As an application, we run our algorithm on a sample…

Astrophysics of Galaxies · Physics 2016-07-15 Eman Mahmoud , Ali Takey , Amin Shoukry

In these three lectures a review is provided of the properties of galaxy systems as determined from optical and infrared measurements. Covered topics are: clusters identification, global cluster properties and their scaling relations,…

Astrophysics · Physics 2008-11-24 A. Biviano

I review some of the current efforts to create unbiased samples of galaxy clusters. Readers are referred elsewhere for general wide area sky surveys and redshift surveys, and for Sunyaev-Zeldovich, radio, infrared and submm surveys, some of…

Astrophysics · Physics 2007-05-23 Isabella M. GIOIA

The detection of galaxy clusters in present and future surveys enables measuring mass-to-light ratios, clustering properties or galaxy cluster abundances and therefore, constraining cosmological parameters. We present a new technique for…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-17 Begoña Ascaso , David Wittman , Narciso Benítez , the DLS collaboration

The theme of this book chapter is to discuss algorithms for identifying and reconstructing groups and clusters of galaxies out of the general galaxy distribution. I review the progress of detection techniques through time, from the very…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-24 C. Marinoni

We have developed a method for detecting clusters in large imaging surveys, based on the detection of structures in galaxy density maps made in slices of photometric redshifts. This method was first applied to the Canada France Hawaii…

A new approach to the study of the large-scale stellar cluster distribution in the Galaxy based on two-point correlation techniques is presented. The basic formalism for this method is outlined and its applications are then investigated by…

Astrophysics · Physics 2009-10-30 M. Lopez-Corredoira , F. Garzon , P. L. Hammersley , T. J. Mahoney

Studies of galaxy clusters have proved crucial in helping to establish the standard model of cosmology, with a universe dominated by dark matter and dark energy. A theoretical basis that describes clusters as massive, multi-component,…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-26 Steven W. Allen , August E. Evrard , Adam B. Mantz

A new method for a simultaneous search for clusters of galaxies in X-ray photon maps and optical galaxy maps is described. The merging of X-ray and optical data improves the source identification so that a large amount of telescope time for…

Astrophysics · Physics 2009-11-10 Peter Schuecker , Hans Boehringer , Wolfgang Voges

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

Over the past several decades, advances in telescope/detector technologies and deep imaging techniques have pushed surface brightness limits to ever fainter levels. We can now both detect and measure the diffuse, extended star light that…

Astrophysics of Galaxies · Physics 2019-09-23 J. Christopher Mihos

The classification of galaxy morphologies is an important step in the investigation of theories of hierarchical structure formation. While human expert visual classification remains quite effective and accurate, it cannot keep up with the…

Instrumentation and Methods for Astrophysics · Physics 2023-10-13 Matthew J. Baumstark , Giuseppe Vinci

The Sloan Digital Sky Survey has obtained 450 square degrees of photometric scan data, in five bands (u',g',r',i',z'), which we use to identify clusters of galaxies. We illustrate how we do star-galaxy separation, and present a simple and…

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

In this paper, we present the tools used to search for galaxy clusters in the Kilo Degree Survey (KiDS), and our first results. The cluster detection is based on an implementation of the optimal filtering technique that enables us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-08 M. Radovich , E. Puddu , F. Bellagamba , M. Roncarelli , L. Moscardini , S. Bardelli , A. Grado , F. Getman , M. Maturi , Z. Huang , N. Napolitano , J. McFarland , E. Valentijn , M. Bilicki

Based on the photometric redshift catalog of Zou H. et al. (2019), we apply a fast clustering algorithm to identify 540,432 galaxy clusters at $z\lesssim1$ in the DESI legacy imaging surveys, which cover a sky area of about 20,000 deg$^2$.…

Astrophysics of Galaxies · Physics 2021-04-21 Hu Zou , Jinghua Gao , Xin Xu , Xu Zhou , Jun Ma , Zhimin Zhou , Tianmeng Zhang , Jundan Nie , Jiali Wang , Suijian Xue

This work identifies the orientation of galaxies in the Galaxy zoo data set. The images are first identified by the number of principal components required to represent 99 percent of the variance of the image. K means clustering is used to…

Astrophysics of Galaxies · Physics 2020-10-27 Vijay Shankar A

The 2dF Galaxy Redshift Survey has now been completed and has mapped the three-dimensional distribution, and hence clustering, of galaxies in exquisite detail over an unprecedentedly large ($\sim 10^{8} h^{-3}$ Mpc$^{3}$) volume of the…

Astrophysics · Physics 2007-05-23 Warrick Couch , Matthew Colless , Roberto De Propris

We discuss the implementation and validation of a procedure aimed to detect groups and clusters of galaxies in DPOSS catalogs.

Astrophysics · Physics 2007-05-23 E. Puddu , E. De Filippis , V. Strazzullo , S. Andreon , G. Longo , R. Gal , S. Djorgovski , R. Scaramella