TUESADAY
31 March 2009
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Anca Constantin (Harvard Smithsonian CfA)
"Lessons on galactic nuclear activity from cosmic voids"
Galaxies in the most underdense regions of the universe, the voids,
must have different evolutionary histories than those in denser
regions, the walls. This is mainly because of the expected huge
difference in their rate of interactions, which is believed to affect
the nuclear activity, and thus the growth process. It is thus
important to determine the degree to which the void galactic nuclear
activity compares to its counterpart in denser environments. I will
present the results of a comparison of void and wall systems based on
a variety of physical properties and near neighbor statistics,
together with spatial clustering calculations, which provide empirical
evidence that both small and large scale environment influence the
interplay between AGN and nuclear stellar activity, and thus the
optically dominant power source. I will present these ideas in the
context of a potential H II -> Seyfert/Transition Object -> LINER
evolutionary sequence, and show support for this scenario with new
Chandra X-ray measurements.
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