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OATS-DAUT SEMINAR
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Speaker: Enrico Maria Corsini (Univ. di Padova)

Title: Dark matter distribution and gas fueling in the center of barred galaxies

Date: Wednesday, November 15th, 2006
Time: 12:00 noon
Venue: Villa Bazzoni

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Abstract:
The dynamics of a barred galaxy depends on the pattern speed of its bar. The only direct method for measuring the bar pattern speed is the Tremaine-Weinberg technique. This method is best suited to gas-poor galaxies and therefore it has been restricted to early-type barred galaxies. On the other hand, a variety of indirect methods, which are based on the analysis of the distribution and dynamics of the gaseous component, has been used to measure the bar pattern speed in late-type barred galaxies. Nearly all the measured bars are as rapidly rotating as they can be. By comparing these results with recent high-resolution N-body simulations of bars in cosmologically-motivated dark matter halos, it is possible to conclude that these bars are not located inside centrally-concentrated halos. The Tremaine-Weinberg technique also permitted us to establish directly that nested bars are rotating with different pattern speeds and, in particular, that the rotation frequency of the secondary bar is higher than that of the primary one. This makes double bars efficient agents in fueling the AGN activity.
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