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Selection effects on X-ray and strong-lensing clusters in various cosmologies

C. Fedeli·M. Bartelmann
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Abstract

Galaxy clusters are hotter and more X-ray luminous than in quiescence while they undergo major mergers, which also transiently increase their strong-lensing efficiency. We use semi-analytic models for both effects to study how cluster dynamics in different dark-energy models affects the X-ray selected cluster population and its strong-lensing optical depth. We find that mergers increase the number of observable X-ray clusters by factors of a few and considerably broaden their redshift distribution. Strong-lensing optical depths are increased by a very similar amount. Quite independent of cosmology, X-ray bright clusters above a flux limit of $10^{-13.5} \mathrm{erg s^{-1} cm^{-2}}$ produce $\sim60%$ of the strong-lensing optical depth, and only $\sim1%$ above a flux limit of $10^{-11.5} \mathrm{erg s^{-1} cm^{-2}}$ if mergers are taken into account.

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C. Fedeli, M. Bartelmann. 2007-09-25. Selection effects on X-ray and strong-lensing clusters in various cosmologies. https://doi.org/10.1051/0004-6361%3A20077572

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