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A Simple Measurement of Turbulence in Cores of Galaxy Clusters

Yutaka Fujita
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Abstract

Using a simple model, we study the effects of turbulence on the motion of bubbles produced by AGN jet activities in the core of a galaxy cluster. We focus on the turbulence with scales larger then the size of the bubbles. We show that for a bubble pair with an age of ~10^8 yr, the projected angle between the two vectors from the cluster center to the two bubbles should be ~> 90 degree and the ratio of their projected distances from the cluster center should be ~< 2.5, if the velocity and scale of the turbulence are ~250 km s^-1 and ~20 kpc, respectively. The positions of the bubbles observed in the Perseus cluster suggest that the turbulent velocity is ~>100 km s^-1 for the cluster.

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Yutaka Fujita. 2005-08-10. A Simple Measurement of Turbulence in Cores of Galaxy Clusters. https://doi.org/10.1086/496972

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