New Tests of the Cluster Entropy Floor Hypothesis

Ian G. McCarthy; Arif Babul; Michael L. Balogh; Gilbert P. Holder

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New Tests of the Cluster Entropy Floor Hypothesis

Ian G. McCarthy·Arif Babul·Michael L. Balogh·Gilbert P. Holder

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Abstract

Recent efforts to account for the observed X-ray luminosity - temperature relation of galaxy clusters has led to suggestions that the ICM has an apparent ``entropy floor'' at or above the level of 300 keV cm^2. Here, we propose new tests based on the thermal Sunyaev-Zeldovich effect and on the cluster gas mass - temperature trend (from X-ray data) to probe the level of excess entropy in the ICM. We show that these new tests lend further support to the case for a high entropy floor in massive clusters.

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BibTeX RIS

Ian G. McCarthy, Arif Babul, Michael L. Balogh, Gilbert P. Holder. 2002-07-05. New Tests of the Cluster Entropy Floor Hypothesis. https://arxiv.org/abs/astro-ph/0207147

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