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The Origin of Ripples in Cool Cores of Galaxy Clusters: Heating by MHD Waves?

Yutaka Fujita·Takeru K. Suzuki·Takahiro Kudoh·Takaaki Yokoyama
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Abstract

We consider MHD waves as a heating source of cool cores of galaxy clusters. In particular, we focus on transverse waves (Alfven waves), because they can propagate a longer distance than longitudinal waves (sound waves). Using MHD simulations, we found that the transverse waves can stably heat a cool core if the wave period is large enough (>~ 10^8 yr). Moreover, the longitudinal waves that are created as a by-product of the nonlinear evolution of the transverse waves could be observed as the 'ripples' found in cool cores.

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Yutaka Fujita, Takeru K. Suzuki, Takahiro Kudoh, Takaaki Yokoyama. 2007-03-02. The Origin of Ripples in Cool Cores of Galaxy Clusters: Heating by MHD Waves?. https://doi.org/10.1086/516823

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