http://arxiv.org/abs/1805.02689
Recent Chandra X-ray observations of many galaxy clusters find evidence for hot metal-rich outflows preferentially aligned with the large-scale axes of X-ray cavities with typical outflow masses of around 10^9 – 10^10M_solar. Here we perform a suite of three hydrodynamic simulations to investigate whether AGN jets could drive these metal-rich outflows in a representative cluster. By using both the tracer variable and virtual particle methods, and additionally following the gas metallicity evolution, we show that metal-rich gas initially located in central regions can indeed be uplifted by the AGN bubble to large distances, a phenomenon called Darwin drift in fluid mechanics, and forming a filamentary trailing outflow extending beyond 100 kpc behind the bubble. The gas entrained in the trailing outflow is entirely outflowing with an average outflow rate of nearly 100M_soalr/yr during the first 100 Myr, and at later times, a growing lower part flows back towards the cluster center due to gravity. The outflow mass rises up to about 10^10M_solar, consistent with observations and predictions from the drift model, and by the end of our simulation (~800 Myr after the AGN event), several 10^9M_soalr of the uplifted high-metallicity gas still remains at large altitudes, potentially contributing to the enrichment of the bulk ICM and the broadening of central metallicity peaks observed in cool core clusters.
X. Duan and F. Guo
Wed, 9 May 18
15/55
Comments: 9 pages, 5 figures
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