UZH-Logo

Maintenance Infos

The Voronoi Tessellation cluster finder in 2+1 dimensions


Soares-Santos, M; de Carvalho, R R; Annis, J; Gal, R R; La Barbera, F; Lopes, P A A; Wechsler, R H; Busha, M T; Gerke, B F (2010). The Voronoi Tessellation cluster finder in 2+1 dimensions. Astrophysical Journal, 727(1):45.

Abstract

We present a detailed description of the Voronoi Tessellation (VT) cluster finder algorithm in 2+1 dimensions, which improves on past implementations of this technique. The need for cluster finder algorithms able to produce reliable cluster catalogs up to redshift 1 or beyond and down to $10^{13.5}$ solar masses is paramount especially in light of upcoming surveys aiming at cosmological constraints from galaxy cluster number counts. We build the VT in photometric redshift shells and use the two-point correlation function of the galaxies in the field to both determine the density threshold for detection of cluster candidates and to establish their significance. This allows us to detect clusters in a self consistent way without any assumptions about their astrophysical properties. We apply the VT to mock catalogs which extend to redshift 1.4 reproducing the $\Lambda$CDM cosmology and the clustering properties observed in the SDSS data. An objective estimate of the cluster selection function in terms of the completeness and purity as a function of mass and redshift is as important as having a reliable cluster finder. We measure these quantities by matching the VT cluster catalog with the mock truth table. We show that the VT can produce a cluster catalog with completeness and purity $>80%$ for the redshift range up to $\sim 1$ and mass range down to $\sim 10^{13.5}$ solar masses.

We present a detailed description of the Voronoi Tessellation (VT) cluster finder algorithm in 2+1 dimensions, which improves on past implementations of this technique. The need for cluster finder algorithms able to produce reliable cluster catalogs up to redshift 1 or beyond and down to $10^{13.5}$ solar masses is paramount especially in light of upcoming surveys aiming at cosmological constraints from galaxy cluster number counts. We build the VT in photometric redshift shells and use the two-point correlation function of the galaxies in the field to both determine the density threshold for detection of cluster candidates and to establish their significance. This allows us to detect clusters in a self consistent way without any assumptions about their astrophysical properties. We apply the VT to mock catalogs which extend to redshift 1.4 reproducing the $\Lambda$CDM cosmology and the clustering properties observed in the SDSS data. An objective estimate of the cluster selection function in terms of the completeness and purity as a function of mass and redshift is as important as having a reliable cluster finder. We measure these quantities by matching the VT cluster catalog with the mock truth table. We show that the VT can produce a cluster catalog with completeness and purity $>80%$ for the redshift range up to $\sim 1$ and mass range down to $\sim 10^{13.5}$ solar masses.

Citations

25 citations in Web of Science®
6 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

18 downloads since deposited on 23 Feb 2012
5 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute for Computational Science
Dewey Decimal Classification:530 Physics
Language:English
Date:2010
Deposited On:23 Feb 2012 22:07
Last Modified:05 Apr 2016 15:40
Publisher:Institute of Physics Publishing
ISSN:0004-637X
Publisher DOI:10.1088/0004-637X/727/1/45
Related URLs:http://arxiv.org/abs/1011.3458
Permanent URL: http://doi.org/10.5167/uzh-60056

Download

[img]
Preview
Content: Accepted Version
Language: English
Filetype: PDF
Size: 946kB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations