Open AccessHeating cooling flows with jets
Author(s) -
Omma Henrik,
Binney James,
Bryan Greg,
Slyz Adrianne
Publication year - 2004
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2004.07382.x
Subject(s) - physics , cooling flow , astrophysics , vortex , adaptive mesh refinement , mechanics , radiative cooling , active galactic nucleus , mixing (physics) , flow (mathematics) , cluster (spacecraft) , galaxy , quantum mechanics , computer science , thermodynamics , programming language
Active galactic nuclei are clearly heating gas in ‘cooling flows’. The effectiveness and spatial distribution of the heating are controversial. We use three‐dimensional simulations on adaptive grids to study the impact on a cooling flow of weak, subrelativistic jets. The simulations show cavities and vortex rings as in the observations. The cavities are fast‐expanding dynamical objects rather than buoyant bubbles as previously modelled, but shocks still remain extremely hard to detect with X‐rays. At late times the cavities turn into overdensities that strongly excite the g modes of a cluster. These modes damp on a long time‐scale. Radial mixing is shown to be an important phenomenon, but the jets weaken the metallicity gradient only very near the centre. The central entropy density is modestly increased by the jets. We use a novel algorithm to impose the jets on the simulations.