Article

A multicomponent matched filter cluster confirmation tool for eROSITA: initial application to the RASS and DES-SV data sets

Matthias KleinMax Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, D-85748 Garching, GermanyJ. J. MohrExcellence Cluster Universe, Boltzmannstr. 2, D-85748 Garching, GermanyS. DesaiDepartment of Physics, IIT Hyderabad, Kandi, Telangana 502285, IndiaH. IsraelFaculty of Physics, Ludwig-Maximilians-Universität, Scheinerstr. 1, D-81679 Munich, GermanyS. AllamFermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USAA. Benoit-LévyDepartment of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, UKDavid BrooksDepartment of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, UKE. Buckley‐GeerFermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USAA. Carnero RosellObservatório Nacional, Rua Gal. José Cristino 77, Rio de Janeiro, RJ-20921-400, BrazilM. Carrasco KindDepartment of Astronomy, University of Illinois, 1002 W. Green Street, Urbana, IL 61801, USAC. E. CunhaKavli Institute for Particle Astrophysics & Cosmology, P.O. Box 2450, Stanford University, Stanford, CA 94305, USAL. N. da CostaLaboratório Interinstitucional de e-Astronomia – LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ-20921-400, BrazilJ. P. DietrichExcellence Cluster Universe, Boltzmannstr. 2, D-85748 Garching, GermanyT. F. EiflerJet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, USAA. E. EvrardDepartment of Astronomy, University of Michigan, Ann Arbor, MI 48109, USAJ. FriemanKavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637, USAD. GruenKavli Institute for Particle Astrophysics & Cosmology, P.O. Box 2450, Stanford University, Stanford, CA 94305, USAR. A. GruendlNational Center for Supercomputing Applications, 1205 West Clark St., Urbana, IL 61801, USAG. GutiérrezFermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USAK. HonscheidCenter for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, OH 43210, USAD. J. JamesCerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena, ChileK. KuehnAustralian Astronomical Observatory, North Ryde, NSW 2113, AustraliaM. LimaLaboratório Interinstitucional de e-Astronomia – LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ-20921-400, BrazilM. A. G. MaiaLaboratório Interinstitucional de e-Astronomia – LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ-20921-400, BrazilM. MarchDepartment of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USAP. MelchiorDepartment of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544, USAF. MenanteauDepartment of Astronomy, University of Illinois, 1002 W. Green Street, Urbana, IL 61801, USAR. MiquelInstitució Catalana de Recerca i Estudis Avançats, E-08010 Barcelona, SpainA A PlazasJet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, USAK. ReilSLAC National Accelerator Laboratory, Menlo Park, CA 94025, USAA. K. RomerDepartment of Physics and Astronomy, Pevensey Building, University of Sussex, Brighton BN1 9QH, UKE. SánchezCentro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, SpainB. X. SantiagoInstituto de Física, UFRGS, Caixa Postal 15051, Porto Alegre, RS-91501-970, BrazilV. ScarpineFermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USAM. SchubnellDepartment of Physics, University of Michigan, Ann Arbor, MI 48109, USAI. Sevilla-NoarbeCentro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, SpainM. SmithSchool of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UKM. Soares-SantosFermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USAF. SobreiraLaboratório Interinstitucional de e-Astronomia – LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ-20921-400, BrazilE. SuchytaComputer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USAM. E. C. SwansonNational Center for Supercomputing Applications, 1205 West Clark St., Urbana, IL 61801, USAG. TarléDepartment of Physics, University of Michigan, Ann Arbor, MI 48109, USA

2017en

ABI

Abstract

We describe a multicomponent matched filter (MCMF) cluster confirmation tool designed for the study of large X-ray source catalogues produced by the upcoming X-ray all-sky survey mission eROSITA. We apply the method to confirm a sample of 88 clusters with redshifts 0.05 &lt; z &lt; 0.8 in the recently published 2RXS catalogue from the ROSAT All-Sky Survey (RASS) over the 208 deg2 region overlapped by the Dark Energy Survey (DES) Science Verification (DES-SV) data set. In our pilot study, we examine all X-ray sources, regardless of their extent. Our method employs a multicolour red sequence (RS) algorithm that incorporates the X-ray count rate and peak position in determining the region of interest for follow-up and extracts the positionally and colour-weighted optical richness λMCMF as a function of redshift for each source. Peaks in the λMCMF-redshift distribution are identified and used to extract photometric redshifts, richness and uncertainties. The significances of all optical counterparts are characterized using the distribution of richnesses defined along random lines of sight. These significances are used to extract cluster catalogues and to estimate the contamination by random superpositions of unassociated optical systems. The delivered photometric redshift accuracy is δz/(1 + z) = 0.010. We find a well-defined X-ray luminosity-λMCMF relation with an intrinsic scatter of δln (λMCMF|Lx) = 0.21. Matching our catalogue with the DES-SV redMaPPer catalogue yields good agreement in redshift and richness estimates; comparing our catalogue with the South Pole Telescope (SPT) selected clusters shows no inconsistencies. SPT clusters in our data set are consistent with the high-mass extension of the RASS-based λMCMF-mass relation.

Identifiers

DOI: 10.1093/mnras/stx2929

Citations and references

Cited by 20 references

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