COOL CORE BIAS IN SUNYAEV–ZEL’DOVICH GALAXY CLUSTER SURVEYS
Author(s)
Lin, Henry W.; Benson, Bradford A.; McDonald, Michael A.; Miller, Eric D
DownloadLin-2015-COOL CORE BIAS IN SU.pdf (737.4Kb)
PUBLISHER_POLICY
Publisher Policy
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Terms of use
Metadata
Show full item recordAbstract
Sunyaev–Zel'dovich (SZ) surveys find massive clusters of galaxies by measuring the inverse Compton scattering of cosmic microwave background off of intra-cluster gas. The cluster selection function from such surveys is expected to be nearly independent of redshift and cluster astrophysics. In this work, we estimate the effect on the observed SZ signal of centrally peaked gas density profiles (cool cores) and radio emission from the brightest cluster galaxy by creating mock observations of a sample of clusters that span the observed range of classical cooling rates and radio luminosities. For each cluster, we make simulated SZ observations by the South Pole Telescope and characterize the cluster selection function, but note that our results are broadly applicable to other SZ surveys. We find that the inclusion of a cool core can cause a change in the measured SPT significance of a cluster between 0.01 and 10% at z > 0.3, increasing with cuspiness of the cool core and angular size on the sky of the cluster (i.e., decreasing redshift, increasing mass). We provide quantitative estimates of the bias in the SZ signal as a function of a gas density cuspiness parameter, redshift, mass, and the 1.4 GHz radio luminosity of the central active galactic nuclei. Based on this work, we estimate that, for the Phoenix cluster (one of the strongest cool cores known), the presence of a cool core is biasing the SZ significance high by ~6%. The ubiquity of radio galaxies at the centers of cool core clusters will offset the cool core bias to varying degrees.
Date issued
2015-03Department
MIT Kavli Institute for Astrophysics and Space ResearchJournal
The Astrophysical Journal
Publisher
IOP Publishing
Citation
Lin, Henry W., Michael McDonald, Bradford Benson, and Eric Miller. “COOL CORE BIAS IN SUNYAEV–ZEL’DOVICH GALAXY CLUSTER SURVEYS.” The Astrophysical Journal 802, no. 1 (March 18, 2015): 34. © 2015 The American Astronomical Society
Version: Final published version
ISSN
1538-4357
0004-637X