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Title: redMaPPer. I. Algorithm and SDSS DR8 catalog

We describe redMaPPer, a new red sequence cluster finder specifically designed to make optimal use of ongoing and near-future large photometric surveys. The algorithm has multiple attractive features: (1) it can iteratively self-train the red sequence model based on a minimal spectroscopic training sample, an important feature for high-redshift surveys. (2) It can handle complex masks with varying depth. (3) It produces cluster-appropriate random points to enable large-scale structure studies. (4) All clusters are assigned a full redshift probability distribution P(z). (5) Similarly, clusters can have multiple candidate central galaxies, each with corresponding centering probabilities. (6) The algorithm is parallel and numerically efficient: it can run a Dark Energy Survey-like catalog in ∼500 CPU hours. (7) The algorithm exhibits excellent photometric redshift performance, the richness estimates are tightly correlated with external mass proxies, and the completeness and purity of the corresponding catalogs are superb. We apply the redMaPPer algorithm to ∼10, 000 deg{sup 2} of SDSS DR8 data and present the resulting catalog of ∼25,000 clusters over the redshift range z in [0.08, 0.55]. The redMaPPer photometric redshifts are nearly Gaussian, with a scatter σ {sub z} ≈ 0.006 at z ≈ 0.1, increasing to σ {sub z} ≈ 0.02more » at z ≈ 0.5 due to increased photometric noise near the survey limit. The median value for |Δz|/(1 + z) for the full sample is 0.006. The incidence of projection effects is low (≤5%). Detailed performance comparisons of the redMaPPer DR8 cluster catalog to X-ray and Sunyaev-Zel'dovich catalogs are presented in a companion paper.« less
Authors:
; ; ;  [1] ;  [2] ;  [3] ;  [4] ; ;  [5] ; ;  [6] ;  [7] ; ;  [8] ;  [9]
  1. SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)
  2. Institute for Theoretical Physics, University of Zürich, 8057 Zürich (Switzerland)
  3. Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Palo Alto, CA 94305 (United States)
  4. Department of Physics, University of Helsinki, FI-00014 Helsinki (Finland)
  5. Physics Department, University of Michigan, Ann Arbor, MI 48109 (United States)
  6. Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States)
  7. Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan)
  8. Service d'Astrophysique, CEA Saclay, F-91191 Gif sur Yvette Cedex (France)
  9. Brookhaven National Laboratory, Upton, NY 11973 (United States)
Publication Date:
OSTI Identifier:
22357113
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 785; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALGORITHMS; CATALOGS; DESIGN; DISTRIBUTION; GALAXIES; GALAXY CLUSTERS; IMPURITIES; ITERATIVE METHODS; MASS; NONLUMINOUS MATTER; PROBABILITY; RANDOMNESS; RED SHIFT; TRAINS; X RADIATION