Abstract. - I will present recent
observational results on the nature and origin of the multi-phase interstellar
medium (ISM) in giant elliptical galaxies, and its role in galaxy evolution
and in fueling the central supermassive black holes. Our results show that the
cold gas in these systems is produced chiefly by thermally unstable cooling
from the hot phase, and that active galactic nuclei are likely to play a
crucial role in clearing giant elliptical galaxies of their cold gas, keeping
them 'red and dead'. Then I will 'zoom out' to the outskirts of galaxy clusters
where we also find hints that supermassive black holes played an important
role in the distant past. Suzaku observations reveal a remarkably homogeneous
distribution of iron out to the virial radius of the nearby Perseus Cluster,
requiring that most of the metal enrichment of the intergalactic medium
occurred before the cluster formed, probably more than ten billion years ago,
during the period of maximal star formation and black ho le activity. Finally,
I will talk about the upcoming Astro-H mission which will revolutionize X-ray
spectroscopy and our understanding of the dynamics of the intra-cluster
medium. - (Image credit:
N. Werner, A. Simionescu and Akihiro Ikeshita)
This week in Sydney:
The Most Massive Galaxies and their Precursors conference
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