A Caltech Library Service

The impact of baryonic cooling on giant arc abundances

Rozo, Eduardo and Nagai, Daisuke and Keeton, Charles and Kravtsov, Andrey (2008) The impact of baryonic cooling on giant arc abundances. Astrophysical Journal, 687 (1). pp. 22-38. ISSN 0004-637X. doi:10.1086/589955.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


Using ray tracing for simple analytic profiles, we demonstrate that the lensing cross section for producing giant arcs has distinct contributions due to arcs formed through image distortion only, and arcs form from the merging of two or three images. We investigate the dependence of each of these contributions on halo ellipticity and on the slope of the density profile, and demonstrate that at fixed Einstein radius, the lensing cross section increases as the halo profile becomes steeper. We then compare simulations with and without baryonic cooling of the same cluster for a sample of six clusters, and demonstrate that cooling can increase the overall abundance of giant arcs by factors of a few. The net boost to the lensing probability for individual clusters is mass dependent, and can lower the effective low-mass limit of lensing clusters. This last effect can potentially increase the number of lensing clusters by an extra 50%. While the magnitude of these effects may be overestimated due to the well-known overcooling problem in simulations, it is evident that baryonic cooling has a nonnegligible impact on the expected abundance of giant arcs, and hence cosmological constraints from giant arc abundances may be subject to large systematic errors.

Item Type:Article
Related URLs:
URLURL TypeDescription
Nagai, Daisuke0000-0002-6766-5942
Additional Information:© 2008 The American Astronomical Society. Received 2006 October 26; accepted 2008 May 8. E. R. would like to thank Scott Dodelson for a careful reading and helpful suggestions throughout the development of this work. This work was supported in part by the Kavli Institute for Cosmological Physics through the grant NSF PHY-0114422. D. N. is supported by the Sherman Fairchild Postdoctoral Fellowship at Caltech. A. V. K. is supported by the National Science Foundation (NSF) under grants AST-0206216 and AST-0239759 and by NASA through grant NAG5-13274. The authors would also like to thank KICP Thunch, where many conversations related to this topic took place.
Funding AgencyGrant Number
Sherman Fairchild FoundationUNSPECIFIED
Subject Keywords:cosmology: theory
Issue or Number:1
Record Number:CaltechAUTHORS:ROZapj08
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:13532
Deposited By: Tony Diaz
Deposited On:14 Aug 2009 15:17
Last Modified:08 Nov 2021 22:38

Repository Staff Only: item control page