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Title: The DAFT/FADA survey. I.Photometric redshifts along lines of sight to clusters in the z=[0.4,0.9] interval

Abstract

As a contribution to the understanding of the dark energy concept, the Dark energy American French Team (DAFT, in French FADA) has started a large project to characterize statistically high redshift galaxy clusters, infer cosmological constraints from Weak Lensing Tomography, and understand biases relevant for constraining dark energy and cluster physics in future cluster and cosmological experiments. Aims. The purpose of this paper is to establish the basis of reference for the photo-z determination used in all our subsequent papers, including weak lensing tomography studies. This project is based on a sample of 91 high redshift (z {ge} 0.4), massive ({approx}> 3 x 10{sup 14} M{sub {circle_dot}}) clusters with existing HST imaging, for which we are presently performing complementary multi-wavelength imaging. This allows us in particular to estimate spectral types and determine accurate photometric redshifts for galaxies along the lines of sight to the first ten clusters for which all the required data are available down to a limit of I{sub AB} = 24./24.5 with the LePhare software. The accuracy in redshift is of the order of 0.05 for the range 0.2 {le} z {le} 1.5. We verified that the technique applied to obtain photometric redshifts works well by comparingmore » our results to with previous works. In clusters, photo-z accuracy is degraded for bright absolute magnitudes and for the latest and earliest type galaxies. The photo-z accuracy also only slightly varies as a function of the spectral type for field galaxies. As a consequence, we find evidence for an environmental dependence of the photo-z accuracy, interpreted as the standard used Spectral Energy Distributions being not very well suited to cluster galaxies. Finally, we modeled the LCDCS 0504 mass with the strong arcs detected along this line of sight.« less

Authors:
; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
988902
Report Number(s):
FERMILAB-PUB-10-364-A
arXiv eprint number arXiv:1008.5318; TRN: US201019%%190
DOE Contract Number:  
AC02-07CH11359
Resource Type:
Journal Article
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCURACY; ENERGY SPECTRA; GALAXIES; GALAXY CLUSTERS; PHYSICS; TOMOGRAPHY; Astrophysics

Citation Formats

Guennou, L, /Northwestern U. /Marseille, Lab. Astrophys., Adami, C, /Marseille, Lab. Astrophys., Ulmer, M P, /Northwestern U. /Marseille, Lab. Astrophys., LeBrun, V, /Marseille, Lab. Astrophys., Durret, F, /Paris, Inst. Astrophys., Johnston, D, /Fermilab, Ilbert, O, /Marseille, Lab. Astrophys., Clowe, D, /Ohio U., Gavazzi, R, /Paris, Inst. Astrophys., Murphy, K, /Ohio U., Schrabback, T, and /Leiden Observ. /Fermilab. The DAFT/FADA survey. I.Photometric redshifts along lines of sight to clusters in the z=[0.4,0.9] interval. United States: N. p., 2010. Web.
Guennou, L, /Northwestern U. /Marseille, Lab. Astrophys., Adami, C, /Marseille, Lab. Astrophys., Ulmer, M P, /Northwestern U. /Marseille, Lab. Astrophys., LeBrun, V, /Marseille, Lab. Astrophys., Durret, F, /Paris, Inst. Astrophys., Johnston, D, /Fermilab, Ilbert, O, /Marseille, Lab. Astrophys., Clowe, D, /Ohio U., Gavazzi, R, /Paris, Inst. Astrophys., Murphy, K, /Ohio U., Schrabback, T, & /Leiden Observ. /Fermilab. The DAFT/FADA survey. I.Photometric redshifts along lines of sight to clusters in the z=[0.4,0.9] interval. United States.
Guennou, L, /Northwestern U. /Marseille, Lab. Astrophys., Adami, C, /Marseille, Lab. Astrophys., Ulmer, M P, /Northwestern U. /Marseille, Lab. Astrophys., LeBrun, V, /Marseille, Lab. Astrophys., Durret, F, /Paris, Inst. Astrophys., Johnston, D, /Fermilab, Ilbert, O, /Marseille, Lab. Astrophys., Clowe, D, /Ohio U., Gavazzi, R, /Paris, Inst. Astrophys., Murphy, K, /Ohio U., Schrabback, T, and /Leiden Observ. /Fermilab. 2010. "The DAFT/FADA survey. I.Photometric redshifts along lines of sight to clusters in the z=[0.4,0.9] interval". United States. https://www.osti.gov/servlets/purl/988902.
@article{osti_988902,
title = {The DAFT/FADA survey. I.Photometric redshifts along lines of sight to clusters in the z=[0.4,0.9] interval},
author = {Guennou, L and /Northwestern U. /Marseille, Lab. Astrophys. and Adami, C and /Marseille, Lab. Astrophys. and Ulmer, M P and /Northwestern U. /Marseille, Lab. Astrophys. and LeBrun, V and /Marseille, Lab. Astrophys. and Durret, F and /Paris, Inst. Astrophys. and Johnston, D and /Fermilab and Ilbert, O and /Marseille, Lab. Astrophys. and Clowe, D and /Ohio U. and Gavazzi, R and /Paris, Inst. Astrophys. and Murphy, K and /Ohio U. and Schrabback, T and /Leiden Observ. /Fermilab},
abstractNote = {As a contribution to the understanding of the dark energy concept, the Dark energy American French Team (DAFT, in French FADA) has started a large project to characterize statistically high redshift galaxy clusters, infer cosmological constraints from Weak Lensing Tomography, and understand biases relevant for constraining dark energy and cluster physics in future cluster and cosmological experiments. Aims. The purpose of this paper is to establish the basis of reference for the photo-z determination used in all our subsequent papers, including weak lensing tomography studies. This project is based on a sample of 91 high redshift (z {ge} 0.4), massive ({approx}> 3 x 10{sup 14} M{sub {circle_dot}}) clusters with existing HST imaging, for which we are presently performing complementary multi-wavelength imaging. This allows us in particular to estimate spectral types and determine accurate photometric redshifts for galaxies along the lines of sight to the first ten clusters for which all the required data are available down to a limit of I{sub AB} = 24./24.5 with the LePhare software. The accuracy in redshift is of the order of 0.05 for the range 0.2 {le} z {le} 1.5. We verified that the technique applied to obtain photometric redshifts works well by comparing our results to with previous works. In clusters, photo-z accuracy is degraded for bright absolute magnitudes and for the latest and earliest type galaxies. The photo-z accuracy also only slightly varies as a function of the spectral type for field galaxies. As a consequence, we find evidence for an environmental dependence of the photo-z accuracy, interpreted as the standard used Spectral Energy Distributions being not very well suited to cluster galaxies. Finally, we modeled the LCDCS 0504 mass with the strong arcs detected along this line of sight.},
doi = {},
url = {https://www.osti.gov/biblio/988902}, journal = {},
number = ,
volume = ,
place = {United States},
year = {2010},
month = {8}
}