Weak-lensing mass calibration of the Sunyaev-Zel'dovich effect using APEX-SZ galaxy clusters
Artikel i vetenskaplig tidskrift, 2019

The use of galaxy clusters as precision cosmological probes relies on an accurate determination of their masses. However, inferring the relationship between cluster mass and observables from direct observations is difficult and prone to sample selection biases. In this work, we use weak lensing as the best possible proxy for cluster mass to calibrate the Sunyaev-Zel'dovich (SZ) effect measurements from the APEX-SZ experiment. For a well-defined (ROSAT) X-ray complete cluster sample, we calibrate the integrated Comptonization parameter, Y-SZ, to the weak-lensing derived total cluster mass, M-500. We employ a novel Bayesian approach to account for the selection effects by jointly fitting both the SZ Comptonization, Y-SZ-M-500, and the X-ray luminosity, Lx-M-500, scaling relations. We also account for a possible correlation between the intrinsic (lognormal) scatter of L-x and Y-SZ at fixed mass. We find the corresponding correlation coefficient to be r = 0.47(-0.35)(+0.24), and at the current precision level our constraints on the scaling relations are consistent with previous works. For our APEX-SZ sample, we find that ignoring the covariance between the SZ and X-ray observables biases the normalization of the Y-SZ-M-500 scaling high by 1-2 sigma and the slope low by similar to 1 sigma, even when the SZ effect plays no role in the sample selection. We conclude that for higher precision data and larger cluster samples, as anticipated from on-going and near-future cluster cosmology experiments, similar biases (due to intrinsic covariances of cluster observables) in the scaling relations will dominate the cosmological error budget if not accounted for correctly.

cosmology: observations

gravitational lensing: weak

methods: statistical

galaxies: clusters: general galaxies: clusters: intracluster medium


A. Nagarajan

Universität Bonn

Universität zu Köln

F. Pacaud

Universität Bonn

M. Sommer

Universität Bonn

M. Klein


Ludwig-Maximilians-Universität München

K. Basu

Universität Bonn

F. Bertoldi

Universität Bonn

A. T. Lee

Lawrence Berkeley Natl Lab, Div Phys

University of California at Berkeley

P. A. R. Ade

Cardiff University

A. N. Bender

McGill University

University of Colorado at Boulder

D. Ferrusca

Instituto Nacional de Astrofísica, Óptica y Electrońica

N. W. Halverson

University of Colorado at Boulder

Cathy Horellou

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik, Extragalaktisk astrofysik

B. R. Johnson

Columbia Univ, Dept Phys, 538 W 120th St

J. Kennedy

McGill University

R. Kneissl

European Southern Observatory Santiago

Atacama Large Millimeter-submillimeter Array (ALMA)

K. M. Menten


C. L. Reichardt

University of Melbourne

C. Tucker

Cardiff University

B. Westbrook

University of California at Berkeley

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 488 2 1728-1759


Subatomär fysik

Astronomi, astrofysik och kosmologi

Sannolikhetsteori och statistik



Mer information

Senast uppdaterat