Tuesday, September 4, 2012

The jet feedback mechanism (JFM): from supernovae to clusters of galaxies. (arXiv:1209.0168v1 [astro-ph.SR])

The jet feedback mechanism (JFM): from supernovae to clusters of galaxies. (arXiv:1209.0168v1 [astro-ph.SR]):
We study the similarities of jet-medium interactions in several quite
different astrophysical systems using 2D and 3D hydrodynamical numerical
simulations, and find many similarities. The systems include cooling flow (CF)
clusters of galaxies, core-collapse supernovae (CCSNe), planetary nebulae
(PNe), and common envelope (CE) evolution. The similarities include hot bubbles
inflated by jets in a bipolar structure, vortices on the sides of the jets,
vortices inside the inflated bubbles, fragmentation of bubbles to two and more
bubbles, and buoyancy of bubbles. The activity in many cases is regulated by a
negative feedback mechanism. Namely, higher accretion rate leads to stronger
jet activity that in turn suppresses the accretion process. After the jets
power decreases the accretion resumes, and the cycle restarts. In the case of
CF in galaxies and clusters of galaxies we also study the accretion process,
which is most likely by cold clumps, i.e., the cold feedback mechanism. In CF
clusters we find that heating of the intra-cluster medium (ICM) is done by
mixing hot shocked jet gas with the ICM, and not by shocks. Our results
strengthen the jet feedback mechanism (JFM) as a common process in many
astrophysical objects.

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