The Origin of Ripples in Cool Cores of Galaxy Clusters: Heating by MHD Waves?
نویسندگان
چکیده
We consider MHD waves as a heating source of cool cores of galaxy clusters. In particular, we focus on transverse waves (Alfvén 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 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. Subject headings: cooling flows — galaxies: active — galaxies: clusters: general — waves — X-rays: galaxies: clusters
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