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arXiv · astro-ph/0106458

Constraints on the Interaction between Dark Matter and Baryons from Cooling Flow Clusters

Abstract

Other nongravitational heating processes are needed to resolve the disagreement between the absence of cool gas components in the centers of galaxy clusters revealed recently by Chandra and XMM observations and the expectations of conventional radiative cooling models. Here we propose that the interaction between dark matter particles and ordinary baryonic matter may act as an alternative for the reheating of intracluster medium (ICM) in the inner regions of clusters, in which kinetic energy of dark matter is transported to ICM to balance the radiative cooling. Using the Chandra and XMM data of typical clusters, we set a useful constraint on the dark matter-baryon cross-section: $σ_{xp}/m_x \sim 1 \times 10^{-25}$ cm$^2$GeV$^{-1}$, where $m_x$ is the mass of dark matter particles.

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Bo Qin, Xiang-Ping Wu. 2001-06-27. Constraints on the Interaction between Dark Matter and Baryons from Cooling Flow Clusters. https://doi.org/10.1103/physrevlett.87.061301

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