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Title: Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias

Abstract

There are well-observed differences between cool-core (CC) and non-cool-core (NCC) clusters, but the origin of this distinction is still largely unknown. Competing theories can be divided into internal (inside-out), in which internal physical processes transform or maintain the NCC phase, and external (outside-in), in which the cluster type is determined by its initial conditions, which in turn leads to different formation histories (i.e., assembly bias). We propose a new method that uses the relative assembly bias of CC to NCC clusters, as determined via the two-point cluster-galaxy cross-correlation function (CCF), to test whether formation history plays a role in determining their nature. We apply our method to 48 ACCEPT clusters, which have well resolved central entropies, and cross-correlate with the SDSS-III/BOSS LOWZ galaxy catalog. We find that the relative bias of NCC over CC clusters is b = 1.42 ± 0.35 (1.6 σ different from unity). Our measurement is limited by the small number of clusters with core entropy information within the BOSS footprint, 14 CC and 34 NCC clusters. Future compilations of X-ray cluster samples, combined with deep all-sky redshift surveys, will be able to better constrain the relative assembly bias of CC and NCC clusters and determine themore » origin of the bimodality.« less

Authors:
; ; ; ; ;  [1];  [2]
  1. Department of Astrophysical Sciences, 4 Ivy Lane, Princeton, NJ 08544 (United States)
  2. Department of Astronomy, University of Geneva, ch. dEcogia 16, CH-1290 Versoix (Switzerland)
Publication Date:
OSTI Identifier:
22663843
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CATALOGS; CORRELATION FUNCTIONS; CORRELATIONS; COSMOLOGY; ENTROPY; GALAXIES; GALAXY CLUSTERS; NONLUMINOUS MATTER; RED SHIFT; STAR CLUSTERS; UNIVERSE; X RADIATION

Citation Formats

Medezinski, Elinor, Battaglia, Nicholas, Cen, Renyue, Gaspari, Massimo, Strauss, Michael A., Spergel, David N., and Coupon, Jean, E-mail: elinorm@astro.princeton.edu. Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias. United States: N. p., 2017. Web. doi:10.3847/1538-4357/836/1/54.
Medezinski, Elinor, Battaglia, Nicholas, Cen, Renyue, Gaspari, Massimo, Strauss, Michael A., Spergel, David N., & Coupon, Jean, E-mail: elinorm@astro.princeton.edu. Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias. United States. doi:10.3847/1538-4357/836/1/54.
Medezinski, Elinor, Battaglia, Nicholas, Cen, Renyue, Gaspari, Massimo, Strauss, Michael A., Spergel, David N., and Coupon, Jean, E-mail: elinorm@astro.princeton.edu. Fri . "Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias". United States. doi:10.3847/1538-4357/836/1/54.
@article{osti_22663843,
title = {Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias},
author = {Medezinski, Elinor and Battaglia, Nicholas and Cen, Renyue and Gaspari, Massimo and Strauss, Michael A. and Spergel, David N. and Coupon, Jean, E-mail: elinorm@astro.princeton.edu},
abstractNote = {There are well-observed differences between cool-core (CC) and non-cool-core (NCC) clusters, but the origin of this distinction is still largely unknown. Competing theories can be divided into internal (inside-out), in which internal physical processes transform or maintain the NCC phase, and external (outside-in), in which the cluster type is determined by its initial conditions, which in turn leads to different formation histories (i.e., assembly bias). We propose a new method that uses the relative assembly bias of CC to NCC clusters, as determined via the two-point cluster-galaxy cross-correlation function (CCF), to test whether formation history plays a role in determining their nature. We apply our method to 48 ACCEPT clusters, which have well resolved central entropies, and cross-correlate with the SDSS-III/BOSS LOWZ galaxy catalog. We find that the relative bias of NCC over CC clusters is b = 1.42 ± 0.35 (1.6 σ different from unity). Our measurement is limited by the small number of clusters with core entropy information within the BOSS footprint, 14 CC and 34 NCC clusters. Future compilations of X-ray cluster samples, combined with deep all-sky redshift surveys, will be able to better constrain the relative assembly bias of CC and NCC clusters and determine the origin of the bimodality.},
doi = {10.3847/1538-4357/836/1/54},
journal = {Astrophysical Journal},
number = 1,
volume = 836,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}
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