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Inflating Fat Bubbles in Clusters of Galaxies by Wide Jets

Assaf Sternberg·Fabio Pizzolato·Noam Soker
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Abstract

We conduct two-dimensional hydrodynamical simulations of jets expanding in the intra-cluster medium (ICM). We find that for a fat, i.e. more or less spherical, bubble attached to the center to be formed the jet should have high momentum flux and a large opening angle. Typically, the half opening angle should be >50 degrees, and the large momentum flux requires a jet speed of \~10,000 km/sec. The inflation process involves vortices and local instabilities which mix some ICM with the hot bubble. These results predict that most of the gas inside the bubble has a temperature of 3x10^8<T<3x10^9 K, and that large quantities of the cooling gas in cooling flow clusters are expelled back to the intra-cluster medium, and heated up. The magnetic fields and relativistic electrons that produce the synchrotron radio emission might be formed in the shock wave of the jet.

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Assaf Sternberg, Fabio Pizzolato, Noam Soker. 2006-12-28. Inflating Fat Bubbles in Clusters of Galaxies by Wide Jets. https://doi.org/10.1086/512122

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