Understanding galaxy formation and evolution from the perspective of (double-) barred galaxies
Astronomy and astrophysics
Friday 26 February 2016
to 11:30 at
Adriana de Lorenzo-Caceres (University of St. Andrews, School of Physics and Astronomy)
The general picture of galaxy formation and evolution includes bars as the main drivers of the internal secular processes affecting the lifetime of disc galaxies. Particularly interesting is the case of double-barred galaxies: at least 20% of all spirals have turned out to host not only one but two bars embedded in them. The processes inducing the formation of these systems represent a challenge for all the numerical simulations and are still under discussion. In the same way a single bar does, double-bar systems might also promote gas inflow and contribute to the internal secular evolution of their host galaxies. Moreover, they have also been proposed as a very efficient mechanism for the feeding of the active galactic nuclei.
All the theoretical hypothesis on the formation and evolution of double-barred galaxies have not been tested due to the lack of observational works focused on these systems. I will present the results obtained from a spectroscopic survey of double-barred galaxies that we are combining with a thorough photometric analysis of their components. The observational evidences will be discussed in the framework of the double bars formation and evolution theories.