Time Coordinate: 3:30 pm 14th Oct. 2016 (Friday)

Space Coordinate: NTHU General Building II, R521

Speaker: Dr. Yu-Ting Wu (ASIAA)

Title: The Dynamical Evolution of Double-barred Galaxies

Abstract:
About one-third of barred-galaxies have smaller secondary bars embedded within outer primary bars, and are so called double-barred galaxies. An important reason for studying double-barred galaxies is that the existence of an inner bar provides a mechanism for driving gas inflow further toward the nucleus of a galaxy.

With high resolution N-body simulations, we explore the formation and evolution of these systems in terms of initial galaxy models dependent on disk thickness and disk kinematics. We show that for suitable initial conditions long-lived double-barred galaxies form, and their lifetime can be greater than 3.5 Gyr, which is compatible with the high frequency of double-barred galaxies. We study their dynamics and determine the evolution of their respective pattern speeds. The pattern speeds and the effective potential neighboring the corotation resonance region are strongly time-dependent in any rotating frame.